The Vital Role of Family Physicians in the Screening and Early Detection of Lynch Syndrome: A Case Report.

Lynch syndrome (LS) is an autosomal dominant disorder associated with an increased risk of colorectal, endometrial, and other malignancies. This report describes the case of a 53-year-old female patient with a significant family history of colorectal cancer. She presented with metrorrhagia and iron deficiency anemia. Given her strong familial cancer history, besides the transvaginal ultrasound, a colonoscopy was performed despite a recent normal result. The new colonoscopy revealed a vegetative and ulcerated neoplasm at the rectosigmoid junction, confirmed as adenocarcinoma by biopsy. Genetic testing identified a pathogenic MLH1 gene variant (c.2041G>A p.Ala681Thr), confirming LS. The patient was referred for Oncology, Gastroenterology, Surgery, and Genetics consultations. A segmental colectomy was performed along with prophylactic surgery, including hysterectomy and salpingo-oophorectomy. This case highlights the vital role of family physicians in recognizing hereditary cancer syndromes, utilizing genograms to expedite diagnosis, and ensuring proper screening for associated extracolonic malignancies in affected families.