Surgical complications after different therapeutic approaches for locally advanced rectal cancer

Table 1 Definition of postoperative surgical complications (during admission and 30 d thereafter)

	Definition
Anastomotic leakage	Any gas or feces collection around the anastomosis after low anterior resection in the drainage tubes; clinical suspicion confirmed by surgery
Perineal wound complications	Perineal wound dehiscence and wound necrosis after abdominoperineal resection resulting from infection
Ileus	Absence of bowel sounds or defecation after 5 d following surgery
Bleeding	Gastrointestinal or abdominal hemorrhage, decrease in hemoglobin level directly after surgery treated conservatively with blood transfusion or by reintervention
Intra-abdominal abscess	Any intra-abdominal fluid collection unrelated to the anastomosis or perineal wound
Abdominal wound complications	Fascial dehiscence, superficial wound infection
Urological complications	Ureter leakage, urinary incontinence, ureter stenosis
Intestinal necrosis	Caused by bowel ischemia
Gastrointestinal perforation	Intestinal contents discharge from abdominal cavity; clinical suspicion confirmed by surgery
Intravenous line infection	Fever, chills and increase in leukocyte count, excluding other infections; the symptoms disappear after removing the intravenous line
Stoma complications	Stoma necrosis, stoma infection, parastomal hernia
General complications	Cardiovascular, pulmonary, neurological events

Table 2 Clavien–Dindo classification of surgical complications

Grade	Definition
I	Any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic and radiologic interventions. Allowed therapeutic regimens are drugs including antiemetics, antipyretics, analgesics and diuretics, and electrolytes and physiotherapy. This grade also includes wound infections opened at the bedside.
II	Requiring pharmacological treatment with drugs other than those allowed for grade I complications. Blood transfusions and total parenteral nutrition are also included.
III	Requiring surgical, endoscopic or radiological intervention
IIIa	Intervention not under general anesthesia
IIIb	Intervention under general anesthesia
IV	Life-threatening complication (including CNS complications)1 requiring IC/ICU management
IVa	Single organ dysfunction (including dialysis)
IVb	Multiple organ dysfunction
V	Death as a result of complications

¹Brain hemorrhage, ischemic stroke, or subarachnoid bleeding, but excluding transient ischemic attacks. Adapted from Clavien–Dindo classification. CNS: Central nervous system; IC: Intermediate care; ICU: Intensive care unit.

Table 3 Patient and treatment characteristics

Characteristics	No. of patients
Age in yr	59 (21–88)
Sex ratio, male: female	721: 485
Zubrod-ECOG-WHO
0	1060
1	106
2	40
3	0
4	0
5	0
Preoperative treatment
25 × 2 Gy with capecitabine	346
10 × 3 Gy	259
None	592
Distance from anal verge
≤ 5 cm	817
5–10 cm	389
Surgery
LAR	894
APR	303
Hartmann procedure	27
No resection	7
Diverting stoma after LAR
Yes	313
No	581
Pathological TNM classification
pT0	70
pT1	59
pT2	326
pT3	661
pT4	81
pN0	687
pN1	284
pN2	226

ECOG-WHO: Eastern Cooperative Oncology Group-World Health Organization; LAR: Low anterior resection; APR: Abdominoperineal resection.

Table 4 Postoperative complications (events during admission and 30 d thereafter)

Complications	Treatment group	No. of patients	Total	Grade 1	Grade 2	Grade 3a	Grade 3b	Grade 4a	Grade 4b	Grade 5	P value
Anastomotic leakage (LAR)	1	236	16		10		6				0.411
	2	151	9		3		6
	3	507	23		16		7
Perineal wound complications (APR)	1	110	13	9	3	1					< 0.001
	2	108	29	14	13	2
	3	85	8	4	3	1
Ileus	1	346	11	2	5		4				0.069
	2	259	14		13		1
	3	592	14	2	12
Bleeding	1	346	10	1	8		1				0.485
	2	259	10	2	7
	3	592	14	2	10		2
Intra-abdominal abscess	1	346	12	2	5	4	1				0.932
	2	259	10		5	2	3
	3	592	20	3	8	6	3
Abdominal wound complications	1	346	10	7	2		1				0.474
	2	259	10	6	4
	3	592	14	11	2		1
Urological complications	1	346	17	10	4		3				0.154
	2	259	16	5	8		3
	3	592	20	12	6		2
Intestinal necrosis	1	346	2				2				0.689
	2	259	3		2		1
	3	592	4				4
Gastrointestinal perforation	1	346	0								1.000
	2	259	0
	3	592	0
Intravenous line infection	1	346	8		8						0.641
	2	259	8		8
	3	592	12		12
Stoma complications	1	269	11	4	7						0.702
	2	228	14	3	11
	3	119	5	2	3
General complications	1	346	36	21	15						0.520
	2	259	34	17	17
	3	592	54	28	25	1

Group 1: Patients received 25 × 2 Gy radiation with capecitabine; Group 2: Patients received 10 × 3 Gy radiation; Group 3: Patients did not receive radiation; LAR: Low anterior resection; APR: Abdominoperineal resection.

Table 5 Logistic regression analysis of anastomotic leakage

Characteristics	Anastomotic leakage
	χ2	OR	95%CI of Exp(B)	P value
Age	1.748	1.542	0.812–2.928	0.186
Sex	1.081	1.410	0.738–2.695	0.299
Distance from anal verge	0.508	1.276	0.653–2.496	0.476
Pathological T stage	13.089	2.620	1.555–4.415	< 0.001
Pathological N stage	1.402	0.768	0.496–1.189	0.236
Preoperative radiotherapy	14.029			0.001
Long course CRT/surgery directly	10.931	3.624	1.689–7.775	0.001
short course RT/surgery directly	9.614	5.150	1.828–14.515	0.002
diverting stoma	15.804	6.211	2.525–15.385	< 0.001

OR: Odds ratio; CRT: Chemoradiotherapy; RT: Radiotherapy.

Table 6 Logistic regression analysis of perineal wound complications

Characteristics	Perineal wound complications
	χ2	OR	95%CI of Exp(B)	P value
Age	1.576	1.508	0.794–2.865	0.209
Sex	1.542	1.513	0.787–2.907	0.214
Distance from anal verge	1.045	1.779	0.590–5.376	0.307
Pathological T stage	0.391	1.121	0.784–1.602	0.532
Pathological N stage	0.791	1.227	0.782–1.927	0.374
Preoperative radiotherapy	16.757			<0.001
long course CRT/surgery directly	1.166	1.692	0.651–4.394	0.280
short course RT/surgery directly	13.184	5.565	2.203–14.057	<0.001

OR: Odds ratio; CRT: Chemoradiotherapy; RT: Radiotherapy.