P3089 - Quadruple Synchronous Colorectal Carcinomas

Ashwini Mulgaonkar, MD, Fei Bao, MD, Eric Swanson, MD, Lynn Weston, MD, John Kuldau, MD
Scripps Clinic, La Jolla, CA

Introduction: Synchronous multiple primary colorectal cancer (SMPCC) is a subtype of colorectal cancer defined by two or more separate primary lesions are found either pre-operatively, intra-operatively, or within a six-month period post-operatively.

Case Description/Methods: We describe a case of an 89-year-old female with a history of iron deficiency anemia who was found to have worsening acute on chronic anemia. She had never had a colonoscopy prior. Family history was significant for a sister diagnosed with colon cancer in her 80s. On colonoscopy, she had severe diverticulosis as well as four separate colon masses – three in the ascending colon and one at 50 cm from the rectum. Biopsies from the ascending colon resulted as three foci of invasive adenocarcinoma, moderately to poorly differentiated with immunohistochemical stains supporting the diagnosis of colonic adenocarcinoma. The biopsy from the mass at 50 cm resulted as a tubular adenoma.
She met with a surgeon who discussed all possible definitive surgical options and ultimately recommended a subtotal colectomy. The surgery went well but unfortunately, she had a prolonged post operative course complicated by septic shock and ileus. Pathology from the resected mass resulted as four separate foci of poorly differentiated, invasive adenocarcinoma.

Discussion: The diagnosis of SMPCC is based on the presence of multiple primary lesions being present simultaneously. If they are found at different time points, they are metachronous. SMPCC are quite rare and account for only 2-4% of all colorectal cancers. Compared to solitary primary colorectal cancers, there is a reported higher prevalence in males. Studies indicate a variability in tumor location but there is a tendency for higher tumor burden in the proximal portion of the colon. Risk factors include inflammatory bowel disease and familial adenomatous polyposis. The definitive treatment includes surgical resection although there is still uncertainty in the optimal surgical approach – total versus subtotal colectomy via extensive resection versus multiple partial resections. Since these patients usually require more extensive surgical resection than patients diagnosed with solitary primary colorectal cancers, many studies have found that SMPCC patients have a higher incidence of postoperative complications and mortality. This case demonstrates the importance of thorough evaluation and assessment of each colon lesion and appropriate diagnosis and treatment of possible synchronous colorectal cancers.


Disclosures:


Ashwini Mulgaonkar, MD, Fei Bao, MD, Eric Swanson, MD, Lynn Weston, MD, John Kuldau, MD. P3089 - Quadruple Synchronous Colorectal Carcinomas, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.