A 76-year-old woman presented with abdominal pain, fever, and a color change in the skin of the abdominal wall. Two weeks before presentation, the patient noticed abdominal pain and fever accompanied with a loss of appetite. Then, gradually, the skin color of the right lower quadrant of the abdomen darkened with deterioration of her general condition. Her medical history included surgeries for dislocations of the hip joint.
Physical examination revealed a body temperature of 37.8 °C, blood pressure of 106/70 mmHg, and heart rate of 129 beats/min. The skin of the right lower abdominal wall, 8 × 3 cm in size, was black and associated with fluctuation and tenderness, indicating an abdominal wall abscess complicated by skin necrosis. The white blood cell count was 19,000/m3 and CRP, 46.04 mg/dl. Laboratory data were otherwise nonspecific except for mild dehydration. Serum CEA (normal range; 0–5 ng/ml) and CA19-9 (normal range; 0–37 U/ml) were 1.2 ng/ml and less than 2 U/ml, respectively. Emergent CT was performed and demonstrated a large abdominal wall abscess of 15 × 12 cm in size, which contained a moderate amount of air (Fig. 1). There was no apparent connection between the abscess and the abdominal cavity, although the ascending colon and the cecum were adjacent to the abscess; though inconclusive at that time, moderate thickening of the colonic wall was noticed.
Emergent surgery was carried out with the preoperative diagnosis of abdominal wall abscess which was derived from the unconfirmed pathology in the adjacent large intestine. The necrotic skin was extirpated, and a huge amount of pus was drained via three additional skin incisions. The abscess cavity was then intensively irrigated with normal saline, and three drains were inserted subcutaneously. There was no connection seen between the abscess and the abdominal cavity. The results of a bacteriological study demonstrated the presence of Escherichia coli and Streptococcus pyogenes.
Postoperatively, the patient was transferred to the intensive care unit where she was treated for sepsis and respiratory failure. During the postoperative period, which was also complicated by a brain infarction, no fecal material was drained from any of the drains.
Thirty-nine days after the initial operation, when the patient was considered to tolerate both mechanical bowel preparation and the examination itself, a colonoscopy was performed. An ulcerated irregular tumor was found in the cecum (Fig. 2). Biopsy revealed a well-differentiated adenocarcinoma. At this time, a CT scan showed a mass that originated from the cecum that invaded into the abdominal wall at the exact site where the wall thickening had been pointed out before the first operation (Fig. 3). There was no evidence of distant metastasis. MRI revealed no brain metastasis. Serum CEA and CA19-9 were 5.7 ng/ml and less than 2 U/ml, respectively. Although several lymph nodes were detected in the bilateral axillary area, because of their size being 1 cm or less, we considered them as nonspecific.
Oncological right hemicolectomy with partial abdominal wall resection was performed with macroscopically curative intent (Fig. 4). Histological examination revealed a well-differentiated adenocarcinoma (T4N1M0) with skin invasion. Proximal and distal margins of the resected specimen were negative; nevertheless, the surgical margin around the site of skin invasion was considered to be pathologically positive for carcinoma. Detailed examination of the skin proved the presence of multiple sites of lymphatic invasion (Fig. 5). The postoperative course was uneventful, and adjuvant chemotherapy was declined by the patient.
Two months after the hemicolectomy, a CT was done for the sake of surveillance, and an enlarged lymph node of 3 cm in diameter was detected in the right axillary region (Fig. 6). There was no distant metastasis. Physical examination and ultrasonography of the breast revealed no mass in bilateral breasts. Serum CEA and CA19-9 were 1.9 ng/ml and less than 2 U/ml, respectively. Excisional biopsy of this axillary lymph node was done, and histological examination revealed metastatic adenocarcinoma (Fig. 7).
Twenty-one days later, a local recurrence in the abdominal wall, which had also been detected on CT, performed 2 months after the initial operation, was resected with curative intent. At the same time, systematic axillary lymph node dissection was performed, because CT had showed several lymph nodes in the right axillary region. Twenty nodes were dissected, and histological examination revealed no cancer involvement. Adjuvant chemotherapy was again proposed and declined. The patient was then put on surveillance.