A 58-year-old healthy man with no family history of colorectal cancer or
inflammatory bowel disease presented to our colorectal clinic with a
6-month history of bilateral lower abdominal pain radiating to the back,
5-pound weight loss, and irregular watery bowel movements. He has one
alcoholic drink per day and denied tobacco and recreational drug use.
There was no nausea, vomiting, melena, hematochezia, shortness of
breath, chest pain, dysuria or previous abdominal surgeries. On
presentation his vitals were normal. Physical exam revealed no abdominal
tenderness, distention, or palpable masses.DiagnosisPrior to the colorectal surgery clinic visit, a stool DNA test was
ordered by his primary care physician and was negative. Laboratory
studies were remarkable only for a carcinoembryonic antigen (CEA) level
of 5.9 ng/mL He was initially diagnosed with irritable bowel syndrome.
Colonoscopy performed by the gastroenterologist revealed a long
rectosigmoid stricture that required a gastroscope to negotiate. The
cecum and appendiceal orifice appeared normal.
Biopsies of the rectosigmoid stenosis showed no significant pathologic
abnormality and was non-diagnostic. Computed tomography (CT) imaging of
the abdomen and pelvis demonstrated an irregular rim-enhancing
heterogeneous mass measuring 6.7 cm x 2.8cm, originating from the
base of the cecum and extending across the midline and tethered to the
rectosigmoid junction without evidence of fistula (Figure 1). CT-guided
fine needle aspiration was unsuccessful. The patient was then referred
to the colorectal surgery clinic for further evaluation.Differential DiagnosisConsidering patient symptoms, CT imaging, and endoscopic findings, the
differential diagnosis included possible colorectal malignancy,
perforated appendix with pelvic abscess formation with involvement of
the rectosigmoid junction, perforated colon cancer with abscess
formation, or inflammatory bowel disease with fistula and abscess
formation.TreatmentThe patient underwent an exploratory laparotomy for concern of possible
malignancy and near- obstructing rectosigmoid stricture. An abscess
cavity involving the terminal ileum, distal sigmoid and proximal rectum
was identified. Mobilization of the right colon revealed a pocket of
purulent material posterior to the proximal ascending colon. En-bloc
resection of the terminal ileum, right colon, sigmoid and proximal
rectum was performed with two primary anastomoses (ileocolic and
colorectal) without stomas.OutcomeIntraoperative pelvic fluid cultures grew Streptococcus viridans and the
patient was treated with appropriate antibiotics. Pathology showed
perforated appendiceal moderately differentiated adenocarcinoma with
abscess formation and direct invasion of the rectum without lymph node
involvement (Stage IIC T4bN0Mx, 0/34 lymph nodes). Postoperative course
was unremarkable and the patient was discharged home without
complications and meeting discharge criteria.
The patient was presented at the multidisciplinary tumor board and 6-12
cycles of systemic FOLFOX chemotherapy was recommended because of
high-risk features that included T4 depth of invasion, perforation and
adherence to the rectosigmoid, concern for micrometastasis, and
lymphovascular invasion. However, the patient refused chemotherapy and
instead opted for routine surveillance with CEA levels and CT imaging.
Postoperative CEA level one month after surgery was 1.7 (from 5.9 and
currently 4.3). CT of the chest/abdomen/pelvis 6 months after surgery
showed no evidence of recurrence or metastasis. The patient is now 12
months since surgery without evidence of recurrent disease and training
for a half marathon.