cloacogenic carcinomas ( ccs ) are relatively common neoplasms of the anal canal and are thought to arise from cloacogenic remnants at this site .
histological and ultrastructural studies have indicated that these neoplasms may also arise from transitional cloacogenic epithelium lining the anal ducts or from the basal layer of anal squamous epithelium . outside the anal canal , it has been postulated that these tumors arise from cloacogenic embryologic remnants , squamous metaplastic epithelium , or totipotential basal cells .
we report a patient with cc of the recto - sigmoid junction presenting as intraabdominal abscess . for this reason ,
a 23-year - old man visited the emergency unit of our hospital with rectal bleeding , severe suprapubic abdominal pain , fever , poor general condition and fluid discharge from a median subumbilical incision .
physical examination showed generalized peritonitis in the abdomen and his general condition was moderately dehydrated .
the systolic and diastolic blood pressures were 80 and 50 mm hg respectively , his pulse rate was 110/min , and his respiratory rate was 22/min .
laboratory results were as follows : blood urea nitrogen 65 mg / dl , creatinine 2.1 mg / dl , c - reactive protein 198 mg / l , potassium ( k ) 2.2 meq / dl , and albumin 2.3 g / dl .
blood cell counts revealed leukocytosis ( 215,000/l ) ; his hemoglobin was 10.5 g / dl and the platelet count was 408,000/l .
we performed abdominal computed tomography ( ct ) with intravenous contrast , which showed diffuse wall thickening 10 - 11 cm above the rectosigmoid junction , and an 8  8.5 cm soft tissue lesion that included cystic areas in the pelvis ( fig . 1 , fig .
multiple lymph nodes were seen in the abdomen ; the biggest measured 3  2 cm .
air vesicles and images concordant with a fistula tract in the anterior abdominal wall were detected .
an 8  5 cm abscess was seen related to the fistula tract on the anterior wall of the abdomen .
no intestinal content was observed in the abdomen . a 10 cm mass attached to nearby tissues that contained necrotic and caseated areas covered the distal sigmoid and proximal rectum .
as resection was not possible , hartman - type proximal end colostomy was performed and the operation was ended leaving a distal  stubby. as adenoid structures in patches were observed by histopathological examination , the differential diagnosis was made between poorly differentiated adenocarcinoma and cc .
immunohistochemically , staining with high - molecular - weight cytokeratin ( hmwck ) ( fig .
ca 19 - 9 levels were normal ( 1.1 ng / ml and 2 iu / ml , respectively ) .
three weeks after discharge from the hospital , a 5-fluorouracil + folinic acid + irinotecan regimen was started . in total , three cycles of radiotherapy and a concurrent three - drug chemotherapy regimen ( folfiri ; folinic acid , fluorouracil , irinotecan ) were administered to the patient over 6 weeks . in ct scans 3 months after therapy , an increase in mass size and hydroureteronephrosis were observed . at the end of the fifth month ,
in this case , failure in detecting the mass in the pelvis during laparatomy can depend on two reasons : either the mass was not formed at the time of the laparatomy or the mass could not be seen .
probably it was the colonic mass that caused symptoms of appendicitis in his first surgery .
however , it is normal that colon carcinoma is not suspected initially in an 18-year - old patient presenting with abdominal pain without any family history , since without the presence of familial colon cancer or ulcerative colitis history , incidence of colon cancer is very low at < 40 years of age . in this case , neither in family history nor in colonoscopic examination was any sign of polyposis coli present .
furthermore , because of aggressive progression but nearly normal cea levels , no sign of liver metastasis , and no clinical answer to radiotherapy and chemotherapy , we thought that it was either undifferentiated carcinoma arising from the colonic mucosa or anoderm originated cc which rarely occurs in the rectosigmoid area .
in the literature , most papers report positive reactions with hmwck and p63 immunohistochemical antibodies in cc .
there are only 5 cases of cc located outside the anal canal in the literature .
presented the first case of cc originating from the sigmoid colon and located outside the anal canal .
newell et al . reported a cc case originating from the splenic flexure of the colon with liver metastases .
presented a 24-year - old female patient with cc originating from the descending colon . as a result , although cc generally occurs under the dentate line , rarely it can root from the other sides of the colon .
tumor size < 2 cm , patient age < 40 years , being poor in cells and having high fibroblastic activity are bad prognostic factors .
 cloacogenic carcinoma ( cc , basaloid carcinoma ) generally occurs around the dentate line , rarely it can arise from the other sides of the colon . 
 there are only 5 cases of cc located outside the anal canal in the literature . 
 the first occurrence of a cc presents as intraabdominal abscess . 
 we describe a 23-year - old male patient who was admitted with fever and severe abdominal pain . 
 computed tomography imaging showed diffuse wall thickening about 1011 cm above the rectosigmoid junction , intraabdominal abscess and a soft tissue lession covering the pelvis with a size of 8  8.5 cm including cystic necrotic areas . 
 we performed hartman procedure since the mass was nonresectable . 
 histopathological examination showed cc . in total , 
 three times radiotherapy and a concurrent three - drug regimen of irinotecan , fluorouracil and folinic acid chemotherapy were administered for 6 weeks . as a result , 
 the patient was lost because of multiple organ dysfunction syndrome that developed 3 months after radio - chemotherapy . 
Introduction
Case Report
Discussion
Review of the Literature