Surgery for primary malignant tumors of the abdominal wall: experiences of three African surgical oncology units and review of the literature.

BACKGROUND AND OBJECTIVES: Tumors of the abdominal wall are uncommon but diverse. The surgical challenge is double. The tumor must be completely removed and the abdominal wall repaired. Our aim was to describe the indications, techniques, and results of surgery on these tumors in an African context. METHODS: Retrospective, multicentric and descriptive study conducted in three West African surgical oncology units. We included all abdominal wall tumors followed up between January 2010 and October 2022. Histological type, size, surgical procedure, and method of abdominal wall repair were considered. Survival was calculated using the Kaplan-Meier method and comparisons of proportions were made using the Student t test. RESULTS: We registered 62 tumors of the abdominal wall and we operated on 41 (66.1%). The mean size of the tumors was 14.3 ± 26 cm. Dermatofibrosarcoma and desmoid tumor were present in 33 and 3 cases respectively. In 31.7% of cases in addition to the tumour, the resections carried away the muscular aponeurotic plane. Parietal resections required the use of a two-sided prosthesis in 6 cases. In 13 cases, we used skin flaps. The resections margins were invaded in 5 cases and revision surgery was performed in all of them. Incisional hernia was noticed in 2 cases. The tumor recurrence rate was 12.2% with an average time of 13 months until occurrence. Overall survival at 3 years was 80%. CONCLUSIONS: Surgery is the mainstay of treatment for abdominal wall tumors. It must combine tumor resections and parietal repair. Cancer surgeons need to be trained in abdominal wall repair.

Retroperitoneal GIST: An exceptional location of a rare tumour. A case report from Ouagadougou and review of the literature.

INTRODUCTION: GIST can occur in all segments of the gastrointestinal tract with a predilection for the stomach. Retroperitoneal localization remains exceptional. We report a case to describe our diagnostic and therapeutic approach. CASE PRESENTATION: A 55-year-old patient was admitted with borborygms and a sensation of lumbar swelling for 6 months. He was diabetic and hypertensive. The clinical examination noted a right lumbar mass with perception of bowel sound anterior to the mass, with minimal discomfort and mobility. Ultrasound revealed a hypervascularised, encapsulated, well-limited retroperitoneal tissue mass in contact with the right psoas muscle. Abdomino-pelvic CT scan showed a large, hypervascularized, encapsulated, calcified tissue mass measuring 147 × 106 mm in close contact with the outer edge of the right psoas muscle, suspected of being malignant. MRI noted a suspicious process developed at the expense of the right psoas muscle in its lumbar and iliac portion suggestive of a psoas rhabdomyosarcoma. The patient underwent laparotomy with a retroperitoneal approach by lumbar incision. Histology and immunohistochemistry revealed a GIST expressing CD117. The patient was put on imatinib for 6 months. He is complaint-free after 4 months. DISCUSSION: Despite the rarity of retroperitoneal GIST, it should be considered in the presence of any retroperitoneal mass. This will allow for early management. CONCLUSION: Retroperitoneum is an exceptional location for GIST. Surgery remains the mainstay of curative treatment. Adjuvant imatinib reduces the risk of recurrence. The prognosis is usually good.