Ascending colon cancer and situs inversus totalis: a case report in Sanglah general hospital Denpasar, Bali

ABSTRACT

Situs inversus totalis is a rare congenital condition that occurs in one out of 4,000-20,000 people, characterized by complete transposition of the thoracic and abdominal viscera that creates a mirror image. The etiologic nature of this anomaly is not known. Situs inversus totalis is typically associated with normal life expectancy unless a gastrointestinal or cardiac anomaly is present. This anomaly is not a premalignant condition. Association between colorectal cancer and situs inversus totalis is rare. The transposition of the organs imposes special demands on the diagnostic and technical skills of the surgeon. We report a case of colorectal cancer and situs inversus totalis in a 51-year-old male presenting with intermittent left lower abdominal pain and change of bowel habit since 9 months before admission. We found a palpable solid mass on the left paraumbilical region, mobile, with no tenderness. Laboratory results show moderate anemia with high CEA level. Fecal Occult Blood Test (FOBT) was positive. Plain chest radiography showed suspected situs inversus. We found descending colon tumor on colonoscopy, with histopathology result intramucosal carcinoma. The contrast abdomen CT scan showed situs inversus and irregular thickening on ascending colon with partial stenosis. We performed extended left hemicolectomy and intraoperative we found a mass in the hepatic flexure of the colon with no sign of lymph node and liver metastases. The histopathologic diagnosis was adenocarcinoma moderately differentiated. The patient was diagnosed with adenocarcinoma of ascending colon T3N0M0, stage II.