Merkel cell carcinoma presenting as a nasal dorsum mass: A case report and literature review

Abstract

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer with high incidence in older and immunocompromised patients. Its occurrence in the nasal dorsum is extremely rare and poses significant diagnostic and therapeutic challenges.

CASE SUMMARY

We report the case of a 65-year-old woman with diabetes mellitus and hypertension who presented with a dorsal nasal mass. The initial differential diagnosis favored hemangioma-based clinical examination on imaging. Histopathological examination after excision revealed MCC, necessitating a complex management strategy. A 3 cm × 2 cm nasal mass, initially suspected to be a hemangioma, was excised but revealed MCC with positive margins. Positron emission tomography–computed tomography confirmed metastatic cervical lymphadenopathy. The patient underwent bilateral neck dissection, revealing metastases in seven nodes. Residual activity was treated with radiation therapy, leading to a favorable response after 6 months.

CONCLUSION

This case highlights the importance of considering MCC in the differential diagnosis of nasal masses, and integrated management.

Key Words: Merkel cell carcinoma; Nasal mass; Cancer; Head and neck; Otorhinolaryngology; Case report

Core Tip: Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine skin cancer often misdiagnosed owing to its non-specific presentation. This case report details the diagnostic and therapeutic challenges of MCC in the nasal dorsum of a patient with diabetes and hypertension. Emphasizing multidisciplinary collaboration, it highlights the role of advanced imaging, histopathological analysis, and tailored treatment strategies. By sharing insights from a unique clinical scenario, this report adds to the growing body of literature on MCC and underscores the importance of early recognition and comprehensive care in managing atypical presentations of this malignancy.

INTRODUCTION

Merkel cell carcinoma (MCC) is an uncommon neuroendocrine carcinoma of the skin that predominantly affects sun-exposed areas in older and immunocompromised individuals. The incidence of MCC is low; however, an increase in cases has been observed, likely attributed to heightened awareness of the disease and improved diagnostic methods[1,2]. MCC incidence rises sharply with age; 0.1, 1.0, and 9.8 per 100000 person-years for ages 40–44, 60–64, and 85+, respectively. With the aging population, United States cases are projected to reach 2835 in 2020 and 3284 by 2025[3]. MCC has non-specific physical attributes and typically manifests as a red or pink lesion measuring less than 2 cm. MCC also typically presents intravascular invasion, an increased risk of local recurrence, and distant metastasis, resulting in a high death rate even after surgical excision and treatment[4,5].

In this case report, we comprehensively describe the management approach for nasal dorsum MCC in a patient with diabetes mellitus and hypertension. We emphasize the diagnostic challenges and therapeutic considerations necessitated in this unique clinical scenario. This report will contribute to the growing body of knowledge on MCC by providing unique insights into the management of a rare presentation involving the nasal dorsum, a site not commonly associated with MCC. The implications of this study extend beyond individual patient care, highlighting the importance of accurate diagnosis in atypical presentations, the utility of advanced imaging techniques such as PET-CT, and the role of a multidisciplinary approach in achieving optimal outcomes. Furthermore, it underscores the necessity of heightened awareness among clinicians for early detection, particularly in patients with significant comorbidities, to improve survival rates and reduce recurrence risks in MCC cases.

CASE PRESENTATION

Chief complaints

A 65-year-old woman, with a 10-year history of diabetes mellitus and hypertension and no smoking history, presented with a rapidly enlarging mass in her nasal dorsum.

History of present illness

One year prior, the lesion had the appearance of a 1 cm × 1 cm pimple. The mass was erroneously diagnosed as a hemangioma based on early physical examination and imaging studies. However, significant growth over the following 2 months necessitated referral to our otorhinolaryngology clinic.

History of past illness

A 65-year-old woman with a 10-year history of diabetes mellitus and hypertension, with no history of smoking.

Personal and family history

The patient did not mention any notable personal or family history besides the chronic conditions stated above.

Physical examination

Upon initial presentation, we examined the head and neck, with particular attention to the nasal region. The mass on the nasal dorsum was noted as a large 3 cm × 2 cm pedunculated mass with a wide base over the nasal dorsum (middle 1/3), purple (reddish blue) in color. The remaining head and neck examinations were unremarkable, with no palpable neck lymphadenopathy. Additionally, endoscopic examination revealed no abnormalities in the nasal cavity, and neurological examination identified intact function of all the cranial nerves (CN I–XII) (Figure 1).

Figure 1 Two different angles of the nasal dorsum mass, showing a large 3 × 2 cm pedunculated mass with a wide base over the nasal dorsum (middle 1/3) that was purple (reddish blue) in color. A: Left angle; B: Right angle.

Laboratory examinations

The biopsy of the suspected lymph nodes confirmed the diagnosis of MCC, characterized by neoplastic cells positive for pan-CK, CK20, CK (LMW), CK (AE3), Cam 5.2 (dot-like perinuclear), synaptophysin, and focal chromogranin. The cells tested negative for CK7, CK5/6, TTF1, desmin, actin, S100, CD45, CD3, CD5, and CD20. The Ki-67 proliferative index was approximately 70%, indicating a high-grade neuroendocrine tumor. The primary tumor, measuring 2.8 cm in greatest dimension, was located on the nasal dorsum and affected the epidermis, dermis, and skeletal muscle fibers. Histologically, the tumor exhibited an infiltrative growth pattern with lymphovascular invasion and brisk tumor-infiltrating lymphocytes. No second malignancy was identified. The pathological staging (AJCC 8^th edition) was pT2 Nx. These microscopic and immunohistochemical findings indicate MCC.

Imaging examinations

Doppler ultrasound imaging revealed a superficial heterogeneous soft tissue mass with a hypoechoic appearance and prominent internal vascularity with arterial flow. Subsequently, a magnetic resonance imaging (MRI) of the paranasal sinuses was performed. The MRI depicted a midline cutaneous pedunculated nasal mass that measured 1.8 cm × 1.9 cm × 1.9 cm and featured heterogeneous signals that were predominantly high on T2-weighted images and isointense on T1, along with homogeneous contrast enhancement. The mass was associated with an underlying bone defect but had no intracranial extension or other significant lesions, except for mild inflammatory changes in the left maxillary sinus. This raised the suspicion of either a primary skin lesion or hemangioma (Figures 2 and 3). The preliminary diagnosis was hemangioma owing to the initial clinical appearance and imaging characteristics of the lesion. The mass presented as a reddish blue pedunculated growth, a description commonly associated with vascular lesions such as hemangiomas. Additionally, Doppler ultrasound revealed a superficial heterogeneous soft tissue mass with prominent internal vascularity and arterial flow, findings typical of hemangiomas. Furthermore, the MRI depicted a well-defined, midline cutaneous lesion with no intracranial extension or significantly associated abnormalities, supporting the assumption of a benign vascular lesion. These features, combined with the patient’s unremarkable head and neck examination, led to the initial diagnosis of hemangioma.

Figure 2  Computed tomography scan showing bone involvement of the lesion.

Figure 3 Multiple sequential multiplanar magnetic resonance images of the paranasal sinuses, with IV contrast showing a midline cutaneous pedunculated nasal mass that measured 1.8 cm × 1.9 cm × 1.9 cm in the maximum axial and cell carcinoma dimensions, respectively. A-B: Heterogenous, predominantly high in T2; C-E: Isointense T1 signal with homogenous contrast enhancement in a post-contrast study.

Following the initial surgical intervention to remove the mass, which involved a wide local excision, the defect was repaired using a paramedian forehead flap. Unfortunately, the histopathological examination revealed MCC with positive margins (Figure 4). Owing to this concerning finding, the patient was referred to a tumor board for further discussion and management planning.

Figure 4 Nasal dorsum mass before and after surgery. A: A pedunculated mass in the middle third of the nasal dorsum, with the pen marker showing a paramedian forehead flap before surgery; B: The paramedian forehead flap with excised lesion during surgery; C: Closure of the flap on the nasal dorsum and closure of the flap skin after surgery.

MULTIDISCIPLINARY EXPERT CONSULTATION

Following the patient’s referral to the tumor board and a review of the findings, a multidisciplinary decision was made to proceed with a whole-body positron emission tomography (PET)–CT scan. The head and neck PET-CT scan revealed intensely hypermetabolic upper cervical lymphadenopathy, with specific findings that included a right level 1B lymph node measuring 1.8 cm × 2.8 cm, left level 2A lymph node measuring 0.9 cm × 1.6 cm, and left level 2B lymph node measuring 0.9 cm in diameter.

FINAL DIAGNOSIS

Biopsy of the suspected lymph nodes confirmed the diagnosis of MCC, characterized by neoplastic cells positive for pan-CK, CK20, CK (LMW), CK (AE3), Cam 5.2 (dot-like perinuclear), synaptophysin, and focal chromogranin. The cells were negative for CK7, CK5/6, TTF1, desmin, actin, S100, CD45, CD3, CD5, and CD20. The Ki-67 proliferative index was approximately 70%, supporting a high-grade neuroendocrine tumor. The primary tumor was located on the nasal dorsum, measuring 2.8 cm in greatest dimension, and involving the epidermis, dermis, and skeletal muscle fibers. Histologically, the tumor showed an infiltrative growth pattern, with lymphovascular invasion and brisk tumor-infiltrating lymphocytes. No second malignancy was identified. Pathological staging (AJCC 8^th edition) was pT2 Nx. These microscopic and immunohistochemical findings are consistent with MCC. CT scans of the abdomen, pelvis, and chest revealed no evidence of metastatic disease. Subsequently, we decided to perform bilateral neck dissection with adjuvant therapy to address the locoregional metastasis identified on PET-CT.

The patient underwent modified radical neck dissection from level 1 to 5 lymph nodes bilaterally. The preoperative staging indicated T2N2M0 disease. The pathology report revealed metastatic carcinoma in a total of seven lymph nodes across the right and left levels 1B and left levels 2, 3, and 4 (2/2 in right 1 B, 1/1 in left 1 B, 2/6 in left 2, 3, and 4). A subsequent PET-CT scan showed no residual activity at the primary site or previously dissected submandibular lymph nodes. However, it revealed an increase in the size and metabolic activity of the previously noted bilateral level 2 and 3 cervical lymph nodes. The patient was considered a high-risk patient due to the previously mentioned TNM staging, lymph node metastasis, positive margins from the first excision, and positive lymphovasculer invasion.

TREATMENT

Based on these findings, the tumor board established this patient as high risk and opted for radiation therapy as the initial treatment, with surgery reserved as a salvage option if the patient did not respond to radiation.

OUTCOME AND FOLLOW-UP

The patient completed the treatment course including 30 sessions of radiation therapy and showed complete response to the treatment with no clinical evidence of residual disease after six months of follow-up (Figure 5).

Figure 5 Nasal dorsum from two views after six months of paramedian forehead flap surgery. A: Front angle; B: Overhead angle.

DISCUSSION

MCC primarily affects the head and neck, and frequently spreads to lymph nodes. Its risk factors include sun exposure, immunosuppression, and older age. Early detection improves outcomes, aided by dermoscopy and imaging (ultrasound, MRI, and PET) to assess tumor size and metastasis[6-9].

MCC management focuses on surgical excision with clear margins and sentinel lymph node biopsy to guide treatment. Radiotherapy reduces recurrence risk, while immunotherapy shows promise for advanced cases. A multimodal approach may be needed for high-risk patients. Accurate diagnosis is crucial, as MCC mimics other skin cancers, requiring biopsy and pathology to ensure appropriate treatment[10-12].

In this case, a 65-year-old woman with comorbidities (hypertension and diabetes mellitus) presented with a nasal MCC requiring a paramedian forehead nasal flap and supraomohyoid neck dissection, followed by adjuvant radiotherapy. Despite lymph node involvement in right level 1B and left levels 2B and 2A, no post-surgical complications were observed, and the patient responded well to treatment. This highlights the importance of a multidisciplinary approach and careful tailoring to manage comorbid conditions.

Comparatively, a case in 2022 (56-year-old man) involved a bilateral supraomohyoid neck dissection and adjuvant radiotherapy, with no lymph node involvement or post-surgical complications[13]. Both cases demonstrate effective management of MCC with a surgical and radiotherapeutic approach, but our case is notable for its higher lymph node involvement, likely due to delayed detection caused by the atypical presentation.

A 2018 (83-year-old woman) and a 1987 (61-year-old man) case involved tumor excision alone, with no post-surgical complications or lymph node involvement in the 2018 case, but regional lymph node involvement in the 1987 case[14-16]. This suggests that tumor excision alone may be sufficient in cases with low risk, but lymph node involvement may warrant additional treatment strategies as in our case[14-16].

A 2010 case (63-year-old woman) illustrated a more aggressive disease course with cervical and supracervical lymph node involvement. The management involved tumor excision, bilateral neck dissection, and adjuvant chemotherapy (etoposide) and radiotherapy, but the patient had significant post-surgical complications, including acute necrotic pancreatitis and chronic cholecystitis[16]. In contrast, we avoided chemotherapy due to the patient’s comorbid conditions and demonstrated favorable outcomes, highlighting the need for individualized treatment based on patient factors[16].

Similarly, a 2000 case (79-year-old man) underwent a paramedian forehead nasal flap and neck dissection with adjuvant radiotherapy, resulting in no post-surgical complications[17]. However, lymph node involvement was limited to a single sentinel node in the right neck, compared to the more extensive nodal involvement in our case. This difference underscores the aggressive potential of MCC in some patients, even with similar management[17].

Lastly, a 1995 case (78-year-old woman) involved comorbid chronic lymphatic leukemia and asthma, requiring wide tumor excision and skin grafting along with adjuvant radiotherapy. This case was further complicated by lymph node involvement, including enlarged nodes behind the left jaw and neck. Unlike our case, where the disease was confined to cervical lymph nodes, this case shows the role of systemic comorbidities in influencing disease progression[18].

In summary, our case aligns with cases of the typical demographic of MCC patients, as most are older adults, often in their 60s–80s. Unlike cases with minimal nodal involvement or no comorbidities[13,17], ours involved significant comorbidities (hypertension and diabetes) and extensive lymph node metastases, necessitating a more aggressive approach with surgery and adjuvant radiotherapy, while avoiding chemotherapy. Despite these factors, our case, like most others, had no post-surgical complications, in contrast to the 2010 case[16], which demonstrated severe morbidity, further highlighting the importance of individualized, multidisciplinary management tailored to clinical and pathological features (Table 1).

Table 1 List of published cases on Merkel cell carcinoma in comparison with the current case report.

Ref.	Age (years)	Sex	Comorbid condition	Management	Post-surgical complications	Lymph nodes involvement	Follow up duration/ outcome
Swanson et al[12]	56	Male	None	Bilateral supraomohyoid neck dissection with adjuvant radiotherapy	None	None	At 30-month follow-up, magnetic resonance imaging and computed tomography showed no locoregional recurrence
De Sousa Machado et al[13]	83	Female	None	Tumor excision	None	None	This patient had surgery only and remained disease-free for over 10 years
Nagase et al[14]	63	Female	None	Tumor excision + bilateral neck dissection + adjuvant chemotherapy(etoposide) and radiotherapy	Acute necrotic pancreatitis and chronic cholecystitis	Cervical and supracervical	The patient was last hospitalized in September 2008 for pneumonia and died 17 months after Merkel cell carcinoma diagnosis due to rapid health decline
Rocamora et al[15]	79	Male	None	Paramedian forehead nasal flap and right supraomohyoid neck dissection+ adjuvant radiotherapy	None	Right neck level 1 sentinel node	No evidence of disease at 16 months follow-up postoperatively
Gessner et al[16]	61	Male	History of basal cell carcinoma	Tumor excision	None	Regional lymph nodes involvement	At 18 months, the patient was well with no signs of local or systemic disease
Zeitouni et al[17]	78	Female	Well controlled chronic lymphatic leukemia and asthma	Wide excision of the tumor involving the nasal tip, dorsum of the left side of the nose, and adjacent cheek, with clearance up to the periosteum of the maxilla + skin grafting was performed after the excision with adjuvant radiotherapy	Left parotic mass	Enlarged lymph nodes behind the left jaw angle operation, enlarged left neck lymph node	Currently under follow-up with no clinical evidence of residual disease
This case	65	Female	Hypertension, diabetes mellitus	Paramedian forehead nasal flap + modified radical neck dissection + adjuvant radiotherapy of 30 sessions	None	Right level 1B, left level 2B and 2A	No clinical evidence of residual disease after 6 months follow-up

CONCLUSION

MCC, particularly in rare locations such as the nasal dorsum, presents significant challenges for diagnosis and management. This case report highlights the critical need to suspect atypical presentations, importance of a comprehensive diagnostic approach, and role of a multidisciplinary team in managing such complex patients, especially those with significant comorbidities. Early detection is crucial for improving outcomes, yet diagnosing MCC in uncommon sites remains difficult due to its non-specific appearance. Further research and case reports are essential to develop standardized guidelines for managing MCC in unusual locations.

ACKNOWLEDGEMENTS

We express our sincere gratitude to the patient and their family for their cooperation and willingness to allow their case to contribute to medical knowledge. We also thank Prince Sultan Military Medical City for their support and aid in managing this case and providing the necessary resources for this report. We have ensured that all information has been anonymized, and confidentiality has been maintained to protect the patient's identity, and obtained written informed patient consent for the publication of figures related to the patients’ condition in which the patient may be identifiable.