Small bowel lymphatic malformation: Clinical presentation and a comprehensive literature review

Abstract

Small bowel lymphatic malformations are rare benign tumors of the lymphatic system, accounting for < 1% of intra-abdominal lymphatic malformations. They pose diagnostic challenges due to nonspecific presentations and are often misdiagnosed. To analyze clinical features, management, and outcomes of small bowel lymphatic malformations in adults through a case report and scoping review. A 47-year-old female with chronic abdominal pain underwent laparoscopic resection of an ileal lymphatic malformation. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews-guided scoping review of 97 adult cases (1991-2024) was conducted, extracting demographics, diagnostics, management, and outcomes. The cohort included 41 case reports and 2 case series (46% female, mean age 45.6 years), most commonly presenting with abdominal pain (74%), gastrointestinal bleeding (39%), or asymptomatic masses (9%). Lesions were predominantly in the jejunal mesentery (52%), with a mean size of 9.2 cm. Computed tomography identified lesions in 87% of cases, showing multiloculated cystic masses (78%). Surgical resection was the primary treatment (91%), with segmental bowel resection most frequent (65%). Complications occurred in 24% (infections: 13%), and recurrence in 11% (linked to incomplete resection). Complete excision achieved symptom resolution in 93%. Small bowel lymphatic malformations are rare but may cause significant morbidity. Surgical resection is curative, with laparoscopy emerging as a viable approach. Preoperative diagnosis remains challenging; heightened imaging awareness and complete excision are critical to prevent recurrence.

Key Words: Small bowel lymphatic malformation; Mesenteric cystic lymphatic malformation; Intestinal lymphatic malformation; Surgical resection; Acute abdomen; Clinical presentation

Core Tip: Small bowel lymphatic malformations are rare, benign lymphatic tumors that present diagnostic challenges in adults due to nonspecific symptoms and varied imaging appearances. This report combines a rare ileal lymphatic malformation case with a scoping review of 97 adult cases, highlighting that abdominal pain and gastrointestinal bleeding are the most common presentations. Computed tomography remains the mainstay for detection, but preoperative diagnosis is uncommon. Complete surgical excision, open or laparoscopic, is curative, with recurrence largely linked to incomplete removal. Heightened clinical suspicion, careful imaging interpretation, and radical resection are key to optimal outcomes.

INTRODUCTION

Lymphatic malformations are rare congenital malformations of the lymphatic system, composed of thin-walled, multiloculated cysts that manifest as benign soft tissue tumors[1,2]. They are lesions of vascular origin with lymphatic differentiation, with approximately 95% occurring in the neck and axilla, while the remaining 5% are found in the chest and abdomen[3]. Histologically, lymphatic malformations are classified into macrocystic (cysts > 2 cm), microcystic (cysts < 2 cm), or mixed cystic types, with each subtype differing in clinical behavior and prognosis[2,3].

Abdominal lymphatic malformations are extremely rare, accounting for approximately 1 per 100000 hospital admissions[4]. They have been reported in the mesentery, retroperitoneum, gastrointestinal tract, and intra-abdominal solid viscera[5,6]. The most common locations of intra-abdominal lymphatic malformations include the mesentery, omentum, mesocolon, retroperitoneum, and visceral organs such as the spleen[7,8]. Compared to mesenteric cysts, lymphatic malformations tend to be larger, with a more proliferative and invasive course[7,8].

The clinical presentation of lymphatic malformations varies widely. While some are incidentally discovered on imaging, others present with acute abdominal symptoms[7]. Most cases remain asymptomatic until the tumor is significant[7]. Mesenteric lymphatic malformations, in particular, can lead to complications such as intestinal obstruction or volvulus, which may result in infarction[4-6]. The insidious nature of intra-abdominal lymphatic malformations, combined with the spacious abdominal cavity, often leads to a delayed diagnosis[8]. Additionally, a female predilection has been reported, with a female-to-male ratio of 1:1[9,10]. It is also important to differentiate lymphatic malformations from complex lymphatic anomalies such as generalized lymphatic anomaly, kaposiform lymphangiomatosis, and central conducting lymphatic anomaly, as well as from intestinal lymphangiectasia, since these entities share overlapping features but differ in prognosis and management[11].

Surgical resection remains the treatment of choice for intra-abdominal lymphatic malformations. While the prognosis is generally favorable, increasing tumor size can make radical resection more difficult and increase the risk of local recurrence. Although successful complete removal has been reported, laparoscopy offers a promising alternative approach for the management of these benign tumors[8-11]. To our knowledge, there are limited scoping reviews that have been conducted specifically on mesenteric and small bowel lymphatic malformations. In this study, we report a case of a female patient with small bowel lymphatic malformation and perform a systematic review and analysis of the English literature.

CLINICAL PRESENTATION

A 47-year-old female patient with a past medical history significant for multiple unprovoked deep veins thromboses, four cesarean sections, inguinal hernia repair, right superficial parotidectomy, and two prior episodes of partial small bowel obstruction managed conservatively presented to our general surgical clinic in May 2021. She reported chronic abdominal pain persisting for five years without associated symptoms such as nausea, vomiting, or rectal bleeding. On clinical examination, the patient appeared hemodynamically stable, with normal vital signs. The abdominal examination was unremarkable, revealing a soft, non-tender, and non-distended abdomen. Laboratory investigations were within normal limits.

Imaging and diagnostic workup

The initial computed tomography (CT) scan of the abdomen and pelvis, performed in August 2018, demonstrated segmental thickening of the distal small bowel wall, with surrounding fat stranding and a few enlarged lymph nodes. A repeat CT scan in November 2020 revealed a filling defect in the distal small intestine, along with persistent mesenteric fat stranding and multiple lymph nodes, raising a differential diagnosis of inflammatory enteritis vs a neoplastic process. Subsequent magnetic resonance imaging (MRI) of the abdomen identified cystic lesions in the small intestine within the left lower quadrant, raising suspicion for endometriosis. A capsule endoscopy was performed, revealing erythema of the ileal mucosa without additional specific findings. Upper and lower endoscopic evaluations, including gastroscopy and colonoscopy, were unremarkable. Given the persistence of symptoms and inconclusive imaging findings, a diagnostic laparoscopy was planned, with further surgical intervention contingent upon intraoperative findings (Figure 1).

Figure 1 Axial contrast-enhanced computed tomography scans of the abdomen showing small bowel lymphatic malformation. A: A lobulated, low-attenuation lesion within the mesentery adjacent to small bowel loops (green arrow), suggestive of a lymphatic malformation; B: The lesion appears to contain internal septations and shows no evidence of enhancement (green arrow), consistent with the imaging features of a mesenteric lymphatic malformation.

Surgical findings and management

During the laparoscopy, the small and large intestines were systematically examined. Extensive adhesions were identified and subsequently lysed. A well-defined mass, measuring 8 cm × 6 cm × 3 cm, was observed 2.5 meters proximal to the ileocecal valve. Given its characteristics, en bloc resection of the mass along with a 22 cm segment of the small intestine was performed, followed by a primary end-to-end anastomosis (Figure 2).

Figure 2  A resected small bowel loop with a large mass that arises from the mesentery and involves the small bowel wall.

Histopathological findings

Gross examination of the resected specimen revealed a lobulated mass with multiple cystic spaces containing thick, white fluid. Histopathological analysis confirmed the diagnosis of mesenteric and small intestinal lymphatic malformation (Figure 3).

Figure 3 Histopathological examination of the resected small bowel mass confirming lymphatic malformation. A: Low power magnification (× 10). Small bowel with multiple dilated, thin-walled lymphatic channels within the submucosa and muscularis layers. The cystic spaces are lined with flattened endothelial cells and contain proteinaceous fluid, consistent with lymphatic malformation (hematoxylin and eosin stain). Scale bar = 100 μm; B: High power magnification (× 40). Lymphatic malformation of the small bowel. Seen are multiple, thin-walled endothelial-lined cystic spaces filled with pale eosinophilic fluid, separated by delicate fibrous septa, with scattered lymphocytes (hematoxylin and eosin stain). Scale bar = 50 μm. Stars (A, B): Cystically dilated lymphatic channels with pale eosinophilic proteinaceous material in lumen.

Postoperative course

The patient experienced an uneventful early postoperative recovery and was discharged in stable condition on postoperative day 7. However, on postoperative day 10, she presented to the emergency department with signs of superficial surgical site infection. Wound cultures were negative, and the wound was managed with local wound care, irrigation, and a course of antibiotics. The infection resolved, and she was subsequently discharged in good condition. This case highlights the diagnostic challenges of intra-abdominal lymphatic malformations, given their rarity and nonspecific clinical presentation, and underscores the role of surgical resection as the definitive treatment modality.

LITERATURE REVIEW

This scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews guidelines to systematically map the existing literature on small bowel lymphatic malformation case reports and case series[12].

Information sources and search strategy

The literature search was conducted using three electronic databases: ScienceDirect, PubMed, and Google Scholar, covering all available literature from inception to August 30, 2024. The search strategy incorporated the following keywords and their synonyms: [(“lymphatic malformation” OR “cystic lymphangioma” OR “lymphangiomatous lesion” OR “mesenteric lymphangioma” OR “intestinal lymphatic malformation”) AND (“small intestine” OR “mesentery” OR “abdomen” OR “small bowel” OR “mesenteric” OR “intra-abdominal”) AND (“diagnosis” OR “surgery” OR “resection” OR “laparoscopy” OR “clinical presentation” OR “imaging” OR “histopathology”) AND (“case report” OR “case series”)]. Two researchers independently and concurrently performed the search. All titles, abstracts, and full texts were screened to identify eligible studies.

Eligibility criteria

We included case reports and case series describing adult patients (≥ 18 years) diagnosed with small bowel lymphatic malformation. Articles were included if published in English. We excluded studies that contained duplicate data, did not report small bowel lymphatic malformations, or were published in languages other than English.

Data extraction

From each of the eligible studies, the following information was extracted: First author family name, publication year, gender, age, clinical presentation, duration of symptoms, workup and imaging done, management, location and size of the tumor, histology type, follow-up, and survival status of the patients.

Limitations of data synthesis

Given the nature of the included studies (case reports and small series), formal meta-analysis, calculation of confidence intervals, and stratified statistical comparisons were not feasible. Data are presented as descriptive summaries of aggregated case findings.

EVIDENCE SUMMARY

Demographics and clinical presentations

Our review included 97 patients from 43 studies (46% female, 54% male) with a mean age of 45.6 years (range: 18-76). Notable past histories included abdominal surgeries (e.g., hernia repairs, cholecystectomy; 28%), anemia (22%), and smoking (7%). The most common presentation was abdominal pain (74%), often localized to the epigastrium or lower quadrants, followed by gastrointestinal bleeding (melena/hematochezia; 39%), nausea/vomiting (30%), and asymptomatic masses (9%). Symptom duration varied from acute (< 48 hours; 30%) to chronic (> 3 months; 44%), with anemia-related symptoms (dizziness, fatigue) persisting for years in some cases (Figure 4; Table 1)[4,5,7,13-52].

Figure 4  Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews flow diagram.

Table 1 Patient demographics, clinical features, and diagnostic findings.

Ref.	Gender	Age (years)	Past history	Presentation	Duration of symptoms	Physical exam	Labs	Imaging modality	Site	Size (cm)	Multiplicity	Appearance on imaging
Akwei et al[46]	M	62	Inguinal hernia repair, hiatus hernia	Acute abdominal pain, nausea, vomiting	36 hours	Soft distended abdomen, palpable tender mass; pyrexial (38.2 °C)	↑Amylase (762 unit/dL), ↑ALT (191 IU/L), ↑GGT (508 unit/L)	CT	Proximal small bowel mesentery	25 × 15 × 10	Multiloculated	Large thin-walled multiloculated mass with chylous fluid
Al-Obeed and Abdulla[45]	M	56	Renal stones surgery, tympanoplasty	Epigastric pain, fullness, heartburn, constipation	3 months	Soft/Lax abdomen; no tenderness/rigidity	↑WBC, ↑bilirubin; ↓RBC, ↓HCT, ↓sodium	CT	Ileocecal valve	Not addressed	Not addressed	Small polypoidal mass
Barghash et al[44]	F	26	Post-abortion vaginal bleeding, smoking	Left-sided abdominal pain, distension	24 hours	Distension; tenderness (left iliac fossa/flank)	Leukocytosis; normal LFTs/electrolytes/amylase/CRP/Lactate	CT, MRI	Jejunal mesentery	Approximately 7	Singular (lobulated)	Lobulated low-density mass; peripheral enhancement
Bucciero et al[43]	M	28	Not addressed	Weakness, melena, anemia (Hb 4 g/dL)	Not addressed	Not addressed	Severe anemia	CT	Jejunum	Not addressed	Not addressed	Inhomogeneous mass with stenosis
Cai et al[42]	F	46	Not addressed	Abdominal pain, melena, fatigue, shortness of breath	3 months	Not addressed	Severe anemia (Hb approximately 90 g/L)	EGD, colonoscopy, CE, SBE	Proximal jejunum	6 × 5	Singular (multicystic)	Circumferential submucosal lesion; yellowish-white folds, bleeding points
Chae et al[40]	F	37	None	Severe abdominal pain, epigastralgia, fullness	Months (fullness); 2 weeks (pain)	Not addressed	Not addressed	CT	Jejunal mesentery	9 × 7	Multilocular	Hypodense well-capsulated cystic mass; whirling mesentery, proximal dilation
Chen et al[41]	F	27	None	Abdominal mass, epigastralgia, fullness after meals	Recent	Soft non-tender mass (upper left abdomen); normal bowel sounds	Normal tumor markers	US, MRI	Jejunal mesentery	15 × 8 × 6	Multilocular	Homogeneous mass with septa (MRI); multilocular cystic mass (US)
Chung et al[7]	M	31	None	Sudden severe abdominal pain, fever	Not addressed	Tenderness/guarding; palpable 10-cm hard mass (LLQ)	Leukocytosis (14600/mm3), ↑CRP (82.86 nmol/L)	CT	Jejunal mesentery	8 × 6 × 6	Not addressed	Low-density homogeneous oval; enhancing septum
Creger et al[39]	M	76	None	Incidental mass (asymptomatic)	Asymptomatic	10-cm irregular soft mass	Aspiration cytology was negative for malignancy	CT	Jejunal mesentery	9 × 6 (CT); 10 (exam)	Multiloculated	Multiloculated fluid-filled non-enhancing lesion
Cupido and Low[5]	F	42	Chronic iron deficiency anemia, menorrhagia	Menorrhagia, complex cystic mass	Several years	Not addressed	Not addressed	MRI	Small bowel mesentery	17.6 × 6.8 × 8.7	Multiloculated	Thin-walled multiloculated cyst; high T2/Low T1; no enhancement/solid components
Du et al[38]	M	54	Inguinal hernia surgery	Abdominal mass	4 days	No positive signs	Normal blood/tumor markers (AFP, CEA, CA12-5, CA199)	US, CT	Jejunum/small bowel mesentery	8 × 10	Not addressed	Not addressed
Hwang et al[37]	F	52	Hysterectomy/salpingectomy	Abdominal mass	Not addressed	No positive signs	Normal blood/tumor markers (AFP, CA199, CA12-5)	US, CT	Small bowel mesentery	5 × 5	Not addressed	Irregular low-density mass
Ignjatovic et al[13]	M	71	Angina (5 years)	Rectal hard mass, hematochezia	Not addressed	Hard rectal mass	Normal labs	CT, PET/CT	Jejunum/mesentery	8 × 6	Nodular/multiloculated	Soft-tissue density; hazy attenuations
Honda et al[14]	M	5-75 (range)	Not addressed	Abdominal pain, discomfort, nausea, vomiting	Approximately 6 months	Non-specific	Normal; tumor markers negative	US, MRI (inconclusive)	Ileal mesentery	2 × 1.5 × 1.3	Multiple locules	Lobulated cystic mass; milky fluid
Iwaya et al[36]	F	31	Not addressed	Profound anemia (Hb 53 g/dL)	Not addressed	Not addressed	Anemia; fecal occult blood+	Barium radiography, CT, enteroscopy	Proximal jejunum	3.5 × 3.0	Multicystic	Filling defect (barium); lobulated mass (CT); yellowish-white submucosal tumor
Jang et al[35]	M	70	Hypertension	Iron deficiency anemia, dark stool	3 years	Not addressed	Anemia	CE, DBE	Proximal small bowel	2.0 × 1.7 × 1.2	Singular	Raised granular lesion; white/thickened villi, oozing blood
Jayasundara et al[34]	M	43	Similar abdominal pain 20 years ago	Epigastric pain, nausea, vomiting	20 days (between visits)	Epigastric tenderness/rebound; hyperperistaltic bowel sounds	↑BUN (42.4 mg/dL), ↑creatinine (2.09 mg/dL)	X-ray, CT	Pelvic cavity (small bowel mesentery)	15 × 10 × 6	Multiple locules	Cystic mass; homogeneous fluid; “beaked” small bowel (CT)
João et al[33]	F	18	None	Acute abdominal pain, vomiting	4 hours	Tender (central/LUQ); early peritonism; temp 37.2 °C	Leukocytosis (13900/mm3), ↑CRP (63 nmol/L); normal amylase	CT	Jejunal mesentery	10 × 10 × 9	Two small polyps	Low-density mass encasing vessels
Khan et al[52]	F	29	None	Melena, severe anemia (Hb 55 g/dL)	Not addressed	Not addressed	Microcytic anemia (Hb 55 g/dL)	CE, enteroscopy	Proximal jejunum	1.2	Singular	Whitish “strawberry-like” mucosa, fresh blood
Konstantinidis et al[32]	F	24	None	Sudden right abdominal pain, nausea	Not addressed	Right abdominal tenderness	↑WBC (15.1 L)	CT, endoscopy	Small bowel (mesentery)	0.8-3.5	Not addressed	Well-demarcated thin-walled oval mass
Kopáčová et al[51]	F	31	None	Acute right abdominal pain, nausea	Not addressed	Guarding, tenderness	Mild leukocytosis	US (initially negative)	Mid-ileum	Not addressed	Not addressed	Well-circumscribed whitish multicystic mass
Li et al[31]	M	69	GERD, peptic ulcer, hemorrhoids	Melena, symptomatic anemia	6 months	Pale skin; melena	Anemia (Hb 60-8.5 g/dL)	CE, DBE	Small bowel	0.4 × 0.6	Singular	Nodular lesion (typical lymphatic malformation)
Lim et al[50]	M	70	Iron deficiency anemia	Anemia, dizziness, melena	3 years	Dizziness, weakness	Hb 52 g/dL (pre-operative); Hb 104 g/dL (post-operative)	CE	Jejunum	< 1	Multiple	Mucosal erosion, blood clot; multifocal erosions
Losanoff et al[29]	M	35	Not addressed	Painful abdominal mass	4 weeks	Baseball-sized hard tender mass (RLQ); hypoactive bowel sounds	Normal	CT, MRI	Terminal ileum mesentery	30 × 12 × 10	Single (multiple cysts possible)	Large cyst; soft tissue mass
Mavrogenis et al[30]	M	59	Not addressed	Melena	Not addressed	Not addressed	Anemia	CE, DBE	Proximal jejunum	3.5 × 7	Singular	Polypoid lesion; whitish/red spots, spontaneous bleeding
Botey et al[49]	M	52	Not addressed	Diffuse abdominal pain, diarrhea, and fever	3 days	Tympanic abdomen; diffuse pain, peritoneal irritation	↑CRP (5.8 mg/dL)	CT	Proximal jejunum	7.2 × 9.5 × 7.5	Multilocular	Multilocular cystic mass; thin walls, higher density
Nakamura et al[28]	M	60	Dialysis	Obscure GI bleeding	Not addressed	Not addressed	Not addressed	EUS, DBE	Jejunum	< 1	Not addressed	Hypoechoic mass with erosion/red sign
Stein et al[15]	M	21	Not addressed	GI bleeding, abdominal pain, weight loss	Months	Large nontender abdominal mass	Hb 70 g/dL (HCT 21%)	CT	Mesentery/duodenum	Not addressed	Not addressed	Large infiltrating spongy mass
Ong et al[27]	M	28	None	Recurrent abdominal pain	18 months	Not addressed	Not addressed	CT, MRI	Distal small bowel mesentery/pelvis	Not addressed	Multicystic	Multicystic pelvic lesion
Rieker et al[4]	M	61	Not addressed	Abdominal pain (LLQ), fever to chills/confusion	Not addressed	Not addressed	Not addressed	US, CT	Ileal mesentery	12 × 9 × 7	Multicystic	Multicystic tumor; clear fluid
Rathod et al[26]	F	18	None	Asymptomatic (incidental)	Asymptomatic	Normal	Normal	CT	Jejunal mesentery	10.5 × 10.0 × 6.0	Two cystic swellings	Large well-defined cystic mass; hyperdense fluid, thin capsule/septa
Rojas and Molina[25]	F	71	Cholecystectomy, appendectomy, hysterectomy	Nausea, lower abdominal pain, palpable mass	1 month	Palpable lower abdominal mass	Normal	CT	Small bowel mesentery	9 × 7 × 4	Singular	Mesenteric mass
Lin et al[24]	F	38	Not addressed	Melena, weakness	3 months (melena); 10 days (weakness)	Anemic appearance	Hb 74 g/L; albumin 20.9 g/L	CT	Fundus, peripancreatic, mesenteric, retroperitoneal, spleen	Largest 6.2	Multiple	Multiple small cystic lesions; no enhancement
Safatle-Ribeiro et al[23]	M	30	Pulmonary tuberculosis	Recurrent melena	14 years	Not addressed	Anemia	SBFT, DBE	Jejunum	15 (specimen)	Diffuse	Irregular mucosa; diffuse thickening/nodularity
Samuelson et al[22]	M	70	ADPKD, CHF, valvular cardiomyopathy	Abdominal pain, nausea, emesis, weight loss, hematemesis	Not addressed	Not addressed	Iron deficiency	CT	Jejunum	2.5	Two lymphatic malformations	“Target sign” (intussusception)
Tang et al[47]	F	38	None	Recurrent melena, anemia	Not addressed	1-cm oozing polypoid lesion	Anemia	CE	Proximal-mid small bowel	1	Singular	White-yellow “strawberry” mucosal pattern
Teng et al[21]	F	55	None	Right upper abdominal discomfort	2 months	Mild RUQ tenderness	Normal	CT	Jejunum	3 × 3; 2 × 2	Two	Space-occupying lesion; calcium deposition, enhancement
Tomizawa et al[20]	F	46	Hypothyroidism	Symptomatic anemia	1 year	Pallor	Hb 6 g/dL; iron deficiency	CT enterography	Small bowel mesentery	8.5 × 6 × 4	Lobulated	Large cystic lobulated mass
Torashima et al[19]	F	31	Appendectomy (age 14)	Upper abdominal pain (pregnancy)	24 weeks (gestation)	Abdominal distention, LUQ tenderness	WBC 7600/mm3; Hb 105 g/dL; CRP 0.19 mg/dL	US, CT, MRI	Ileum	19 × 8 × 5.5	Multiloculated	Thin cyst wall; multiloculated cystic lesion
Wei et al[48]	M	21	Known lymphatic malformation	Vomiting, severe LUQ pain	12 hours	Not addressed	Not addressed	CT	Jejunal mesentery	Not addressed	Not addressed	Low-attenuation mass; “swirl sign” (volvulus)
Yang et al[18]	F	37	None	GI hemorrhage, anemia, melena, dizziness	2 weeks	Not addressed	Anemia	CE, CT angiography	Ileum	6.5 × 4.5 × 0.9	Clustered nodules	Cystic: Low T1/high T2 signal
Yavuz et al[17]	F:14 M:8	40.68 (mean)	Not addressed	Abdominal pain (12), distension (6), mass (4), nausea/vomiting (3)	Not addressed	Palpable mass (4), distension (6)	Not addressed	US, CT	Small intestine (18), colon (4)	10.04 (mean; range 2-27)	Not addressed	Not specified
Yeh et al[16]	M:22 F:12	50 (median)	Varied (e.g., choriocarcinoma, gastric cancer)	OGIB (25), abdominal pain (9)	> 3 years (some)	Not addressed	Anemia (OGIB: Hb 63 g/dL)	CT, DBE	Small bowel	Not addressed	Not addressed	Varied (e.g., mass, angiodysplasia)

F: Female; M: Male; GRAD: Gastroesophageal reflux disease; ADPKD: Autosomal dominant polycystic kidney disease; CHF: Congestive heart failure; Hb: Hemoglobin; GI: Gastrointestinal; LLQ: Left lower quadrant; LUQ: Left upper quadrant; OGIB: Obscure gastrointestinal bleeding; RLQ: Right lower quadrant; RUQ: Right upper quadrant; ALT: Alanine aminotransferase; GGT: Γ-glutamyl transpeptidase; WBC: White blood cell; RBC: Red blood cell; HCT: Hematocrit; LFT: Liver function test; CRP: C-reactive protein; AFP: Alpha-fetoprotein; CEA: Carcinoembryonic antigen; CA: Cancer antigen; CT: Computed tomography; MRI: Magnetic resonance imaging; EGD: Esophagogastroduodenoscopy; CE: Capsule endoscopy; SBE: Small bowel enteroscopy; US: Ultrasound; PET: Positron emission tomography; SBFT: Small bowel follow-through.

Diagnostic findings

Physical examination revealed abdominal tenderness (65%), palpable masses (28%), distension (22%), or guarding (13%). Laboratory findings highlighted anemia (hemoglobin < 8 g/dL in 52%), leukocytosis (33%), and elevated amylase/C-reactive protein (17%). Imaging modalities predominantly used CT (87%), supplemented by MRI (26%), ultrasound (22%), and endoscopy (capsule endoscopy/double balloon enterostomy; 39%). Lesions were primarily located in the jejunal mesentery (52%) or ileum (26%), with a mean size of 9.2 cm (range: 0.4-30 cm). Most were multiloculated cystic masses (78%), appearing as thin-walled, fluid-filled lesions with septations (CT/MRI). Multiplicity was noted in 24% of cases (Table 2).

Table 2 Management, histopathology, and outcomes.

Ref.	Management (surgery/endoscopy)	Histopathology findings	Type	Complications (post-operative)	Follow-up duration	Recurrence
Akwei et al[46]	Surgical resection (incomplete)	Complex multiloculated lesion; flattened cells, vascular channels, lymphoid aggregates	Cystic	Infection, pelvic collection (E. coli), required CT-guided drain	1 year	Intra-abdominal collection (1 month); no cyst recurrence
Al-Obeed and Abdulla[45]	Laparoscopic right hemicolectomy	Dilated lymphatic vessels	Cystic	None	Not addressed	Not addressed
Barghash et al[44]	Segmental bowel resection	Dilated thin-walled channels/cystic spaces; flat endothelial cells, lymphocytes, RBCs	Cystic	None	8 weeks	Not specified (risk noted)
Bucciero et al[43]	Surgical resection (duodenum/jejunum)	Dilated lymphatic vessels; histiocytes, lymphangiectasia	Lymphatic malformation	Not addressed	Not addressed	Not addressed
Cai et al[42]	Surgical resection	Dilated lymphatic channels (mucosa/submucosa); simple lymphatic malformation with bleeding	Simple	None	Not specified	No melena recurrence
Chae et al[40]	Surgical resection	Multi-septate cystic masses; flat lymphatic endothelial cells	Cystic (macrocystic)	None	3 months	None
Chen et al[41]	Laparotomy	Dilated lymphatic channels; factor VIII+, actin+, cytokeratin-	Cystic	None	18 months	None
Chung et al[7]	Surgical excision	Dilated lymphatic spaces; collagenous stroma, flattened endothelial cells	Cystic	None	9 months	None
Creger et al[39]	Laparoscopy to open small bowel resection	Lymphatic malformation; no malignancy	Cystic	None	2 weeks	Not addressed
Cupido and Low[5]	Conservative (follow-up); surgery if symptomatic	Not specified (cystic lymphatic malformation)	Cystic	Not addressed	13 months	Not addressed
Du et al[38]	Not specified	Haemolymphangioma (CD34+, D2-40+)	Cystic	None	4 months	None
Hwang et al[37]	Laparoscopic resection	Haemolymphangioma (CD34+, D2-40+)	Cystic	None	4 months	None
Ignjatovic et al[13]	Laparoscopic abdominal transanal resection + ileostomy	Dark red multiloculated cystic lesion; CD34+ endothelial cells	Cavernous	Not addressed	Not addressed	Not addressed
Honda et al[14]	Surgical resection	Cystic lymphatic malformation	Cystic	None	1 year	None
Iwaya et al[36]	Surgical resection	Dilated lymphatic vessels; eosinophilic fluid/RBCs	Lymphatic malformation	Not addressed	Not addressed	Not addressed
Jang et al[35]	Laparoscopic small bowel resection	Dilated vascular channels; D2-40+ (lymphatic), CD31+ (blood)	Hemangiolymphangioma	Not addressed	Not addressed	Not addressed
Jayasundara et al[34]	Segmental resection + anastomosis	Lymphatic malformation	Cystic	Ischemic stricture	20 days	Complete small bowel volvulus
João et al[33]	Surgical excision	Thin-walled lymphatic spaces; eosinophilic material, neutrophils, lymphocytes	Cystic	None	6 months	Not addressed
Khan et al[52]	Endoscopic mucosal resection	Large dilated lymphatic channels	Cavernous	None	2 months	None
Konstantinidis et al[32]	Diagnostic laparoscopy to laparotomy (intussusception)	Cystic lymphatic malformation (irregular cysts)	Cystic	None	2 weeks	Not addressed
Kopáčová et al[51]	Laparoscopic resection	Multicyclic lymphatic malformation; markedly dilated channels	Cystic	None	Not addressed	Not addressed
Li et al[31]	Endoscopic resection (DBE)	Small-bowel lymphatic malformation	Cystic	None	4 months	Not addressed
Lim et al[50]	Surgical resection	Dilated lymphatics; thrombus/hemorrhage	Lymphatic malformation	Chronic anemia/melena (pre-operative); resolved post-op	3 months	None
Losanoff et al[29]	Exploratory laparotomy	Cystic mass; attenuated endothelium, smooth muscle, lymphocytes	Cystic	Hemorrhage, infection, lymphatic fistula (risk)	Not addressed	0%-100% (risk)
Mavrogenis et al[30]	Single-port laparoscopy	Mixed cavernous hemangioma-lymphatic malformation	Mixed	Not addressed	Not addressed	Not addressed
Botey et al[49]	Emergency laparotomy to bowel resection	Mesenteric lymphatic malformation; D2-40+	Cystic	Not addressed	Not addressed	Not addressed
Nakamura et al[28]	Endoscopic mucosal resection	Lymphatic malformation	None	Not addressed	Not addressed
Stein et al[15]	Open biopsy to alcohol ablation	Microcystic lymphatic malformation (small lymphatic channels)	Microcystic	Mild pain/fever (alcohol ablation)	18 months	None (no bleeding recurrence)
Ong et al[27]	Not addressed	Not addressed	Not addressed	Not addressed	Not addressed	Not addressed
Rieker et al[4]	Complete excision	Dilated lymphatic channels; factor VIII+, Ulex europaeus+	Cystic	None (initial); readmitted at 6 months	6 months (readmission)	Possible (incomplete removal risk)
Rathod et al[26]	Surgical excision	Smooth capsulated cysts; chalky white fluid	Cystic	None	Not addressed	Not addressed
Rojas and Molina[25]	Laparotomy	Encapsulated fat; dilated lymph vessels	Cavernous	None	Not specified	None (incomplete resection risk)
Lin et al[24]	Exploratory laparotomy	Dilated lymphatic channels; D2-40+	Cystic	Not addressed	Not addressed	Not addressed
Safatle-Ribeiro et al[23]	Surgical resection	Diffuse dilated lymphatic vessels	Cystic	Bleeding/wall thickness	42 months	None
Samuelson et al[22]	Not addressed	Not addressed	Not addressed	Cachexia, multiple cancers	Not addressed	Not addressed
Tang et al[47]	Laparoscopic segmental resection	Cavernous lymphatic malformation	Cavernous	Not addressed	Not specified (bleeding/anemia resolved)	Not addressed
Teng et al[21]	Excisional surgery	Chronic inflammation; low-grade neoplasia	Hemolymphangioma	None	6 months	None
Tomizawa et al[20]	Exploratory laparotomy	Cystic spaces with hemorrhage; D2-40+	Lymphatic malformation	Not addressed	Not specified	Not addressed
Torashima et al[19]	Laparotomy to bowel resection	Multicyclic spaces; attenuated endothelium, proteinaceous fluid	Cystic	None	18 months	None
Wei et al[48]	Emergency laparotomy to bowel resection	Dilated thin-walled channels; full-thickness bowel involvement	Lymphatic malformation	None	3 months	None
Yang et al[18]	Laparoscopic-assisted resection	Diffuse proliferative blood/Lymphatic vessels	Hemolymphangioma	Not addressed	1 year	Not addressed
Yavuz et al[17]	Enucleation (10), bowel resection (4), laparoscopic excision (4), hemicolectomy (3)	Simple cyst (17), lymphatic malformation (4), adenocarcinoma (1)	Cystic (simple/Lymphangioma)	SSI (3), anastomosis leak (1)	Not addressed	Not addressed
Yeh et al[16]	LABS (27), converted laparotomy (6)	Lymphatic malformation (1 case)	Lymphatic malformation	Transient fever/abdominal pain (tattoo leak)	14 ± 3 months	Symptomatic recurrence (2)

DBE: Double-balloon enteroscopy; LABS: Laparoscopy; RBC: Red blood cell; E. coli: Escherichia coli; SSI: Surgical site infection.

Treatment approaches

Surgical resection was the primary treatment (91%): (1) Segmental bowel resection (65%) for large or symptomatic masses; (2) Laparoscopic excision (26%) for accessible lesions; and (3) Enucleation (9%) for well-defined cysts. Endoscopic resection (9%) was reserved for small, bleeding submucosal lesions (e.g., endoscopic mucosal resection for lymphatic malformations < 2 cm). Incomplete resection occurred in 7% due to adhesions or pancreatic involvement.

Outcomes

Histopathology confirmed cystic lymphatic malformation (76%), cavernous (13%), or hemolymphangioma (11%). Postoperative complications occurred in 24%: Infections (13%), anastomotic leaks (4%), and transient pain/fever (7%). Median follow-up was 12 months (range: 3-42 months). Recurrence was observed in 11% (e.g., intra-abdominal collections, volvulus), primarily after incomplete resection. No recurrence occurred in fully excised lesions. Resolution of symptoms (pain/bleeding) was achieved in 93%, with normalization of hemoglobin in all anemia cases.

Quality assessment with Joanna Briggs Institute checklists for case reports and case series

A total of 43 studies (41 case reports and 2 case series) were appraised using the Joanna Briggs Institute critical appraisal tools. The quality of reporting was variable across the domains. Patient demographics were fully described in 18 studies (41.9%), partially in 10 (23.3%), and omitted in 15 (34.9%). A clear clinical history and timeline were provided in 17 studies (39.5%). The patient’s condition at presentation was the most consistently reported item, with 34 studies (79.1%) providing full details and 1 (2.3%) providing partial details; however, 8 studies (18.6%) did not address it. Diagnostic tests were clearly described in 34 studies (79.1%), while interventions and post-intervention clinical conditions were detailed in 33 (76.7%) and 30 (69.8%) studies, respectively. Adverse events were documented in only a single study (2.3%). Takeaway lessons were included in 29 studies (67.4%). This assessment highlights significant heterogeneity in reporting standards, particularly concerning demographic details, clinical timelines, and outcomes.

Immunohistochemical findings

Among the 97 cases, only 9 (9.3%) reported specific immunohistochemical markers. These included lymphatic markers (D2-40 in 5 cases), vascular markers (CD31 in 1 case, CD34 in 3 cases, factor VIII in 2 cases), and Ulex europaeus in 1 case. No cases reported using more specific lymphatic markers such as prospero homeobox 1 or vascular endothelial growth factor receptor 3.

DISCUSSION

Small bowel lymphatic malformations are exceptionally rare in adults, accounting for less than 1% of all lymphatic malformations and approximately 1 in 100000 hospital admissions. Our review, which included 46% female patients with a mean age of 45.6 years, aligns with the reported female predominance (female to male ratio of 1:1). Although traditionally considered congenital, secondary triggers such as abdominal surgery (noted in 28% of cases), inflammation, or trauma may contribute to the development of these lesions in adults[53-56].

Clinically, abdominal pain was the most prevalent symptom, reported in 74% of cases. This pain was often acute due to complications such as bowel obstruction, including volvulus resulting from mass effect, or chronic in nature from the lesion's insidious growth. Gastrointestinal bleeding occurred in 39% of cases and typically arose from erosion into blood vessels or mucosal ulceration[38,54,57]. In terms of diagnostics, CT scans were the most commonly used imaging modality, applied in 87% of cases. They revealed characteristic multiloculated, fluid-attenuated masses with septations. MRI, which was underutilized (26%), offered enhanced characterization of complex cysts, particularly through T2-hyperintensity signals. Capsule or balloon-assisted enterostomy was valuable in detecting bleeding or submucosal lesions in 39% of cases, though its sensitivity for mesenteric tumors was limited. Anemia, defined by hemoglobin levels below 8 g/dL, was common in bleeding cases (52%), while tumor markers such as carcinoembryonic antigen were typically within normal limits[53,56].

Surgical resection emerged as the gold standard treatment in 91% of cases. Segmental resection, performed in 65% of these, was preferred for large or symptomatic masses to ensure complete excision. Laparoscopic approaches, used in 26%, offered the benefits of minimally invasive surgery and shorter recovery times but often required conversion to open surgery in complex cases involving adhesions. Endoscopic resection proved effective for small submucosal lesions under 2 cm (9% of cases), although bleeding risks limited its broader applicability[38,56]. Postoperative complications were observed in 24% of patients, including surgical site infections in 13% and anastomotic leaks in 4%. Recurrence occurred in 11% of cases and was primarily associated with incomplete resection, particularly when the lesion was adherent to surrounding structures such as the pancreas. Notably, there were no recurrences following complete excision[54,56]. Histopathologically, cystic lymphatic malformation was the most common variant, seen in 76% of cases, and characterized by dilated lymphatic channels lined by endothelial cells. Hemolymphangioma, a mixed vascular and lymphatic form, was identified in 11% and required immunohistochemical confirmation using markers such as CD31, CD34, and D2-40.

However, several important limitations must be acknowledged. First, the included studies consisted predominantly of case reports with significant heterogeneity in reporting standards, particularly concerning demographic details, clinical timelines, and outcomes. Second, as a scoping review of predominantly low-level evidence, formal meta-analysis, calculation of confidence intervals, and stratified statistical comparisons were not methodologically appropriate; our findings should be interpreted as descriptive summaries rather than statistical inferences. Third, immunohistochemical characterization was inconsistently reported, with only 9.3% of cases documenting specific markers, and none reporting contemporary lymphatic markers such as prospero homeobox 1 or vascular endothelial growth factor receptor 3. Finally, publication bias likely led to overrepresentation of symptomatic or complicated cases, while the median follow-up of 12 months may be insufficient to capture late recurrences.

CONCLUSION

In summary, small bowel lymphatic malformations, despite their benign nature, can cause significant morbidity due to mass effect, bleeding, or obstruction. Our case and scoping review underscore key insights. Diagnosis relies on a high index of suspicion, with CT or MRI identifying multiloculated cysts and endoscopy providing supplementary evaluation for mucosal involvement. Management is centered on complete surgical resection, either open or laparoscopic, as it remains definitive. Endoscopic resection should be reserved for small, easily accessible lesions. Prognosis is excellent following complete excision, with 93% symptom resolution and recurrence primarily resulting from residual disease. Future efforts should focus on standardized reporting practices and long-term surveillance to better inform treatment strategies. Clinically, surgeons should maintain a high suspicion for lymphatic malformations when encountering cystic abdominal masses and prioritize radical excision to prevent complications.