Lower Gastrointestinal Bleeding Secondary to Appendiceal Mucinous Neoplasm: A Report of Two Cases and a Review of the Literature

Appendicular mucinous neoplasms, constituting less than 1% of gastrointestinal tract neoplasms, are heterogeneous entities. They may be asymptomatic, discovered incidentally, or present as large tumors due to mucin accumulation. The lack of standardized treatment complicates management. Imaging studies, particularly CT scans, are crucial for diagnosis and follow-up. This case report presents two clinical cases of women in their sixth and seventh decades of life with a history of lower gastrointestinal bleeding, mild anemia in laboratory studies, and incomplete colonoscopies. The diagnosis, confirmed through CT scans, led to the decision for surgical intervention in both cases, involving laparoscopic right hemicolectomy with ileotransverse anastomosis. Subsequently, histopathological reports confirmed the diagnosis of high-grade appendicular mucinous neoplasms, and a follow-up plan was established with imaging studies every six months with no recurrence at two years. Over 50% of appendicular tumors are mucinous neoplasms originating from low-grade mucinous neoplasms. Given the low lymph node invasion (2%), appendectomy may suffice if the entire tumor is excised. Extensive resections or right hemicolectomy are reserved for larger tumors or high-grade neoplasms to minimize local recurrence risk. Mucinous neoplasms with acellular mucin and peritoneal invasion may require cytoreduction or right hemicolectomy, while those with mucinous epithelium may need hyperthermic intraperitoneal chemotherapy (HIPEC) due to the risk of local recurrence, worsened by the presence of extra appendiceal epithelial cells. Disease-free and overall survival depend on treatment and initial lesion characterization. A five-year survival rate of 86% is reported for low-grade mucinous neoplasms. Follow-up approaches lack an ideal standard, generally involving physical examinations and imaging studies every six months to one year during the first six years.

Synchronous Resection of Colon Adenocarcinoma and Bisegmentectomy of Liver Metastases

Colorectal cancer is one of the main neoplasms worldwide; at the time of diagnosis about 25% of cases already have an advanced stage with the presence of metastases. A 58-year-old female presented with nausea, vomiting, and black stools and diffuse abdominal pain associated with 7% weight loss. She was referred to our hospital with signs of digestive tract bleeding and anemic syndrome. Panendoscopy revealed body and fundus gastropathy and presence of Helicobacter pylori, and colonoscopy showed a neoplastic lesion at the ascending colon level. A synchronous resection was performed in a single surgical time of colorectal cancer and liver metastases with a duration of 4 h and bleeding of 900 mL. The oral feeding started 24 h after surgery, presenting gas channeling at 24 h and evacuations at 48 h. The total intrahospital stay was 5 days. Synchronous resection of hepatic metastases in colorectal cancer is still rarely performed, despite the fact that in recent years the number of cases has increased because of better surgical techniques. Synchronous resection of colorectal cancer and liver metastases can be performed safely, without increasing transoperative mortality when performed in specialized centers with a multidisciplinary team; however, it is essential to emphasize the importance of negative surgical margins (R0) of the primary tumor and later to be complemented with adjuvant treatment with chemotherapy.