One case of endometrial cancer occurrence: Over 10 years after colon cancer in Lynch family
A 49-year-old Korean woman visited Samsung Changwon Hospital complaining of irregular menstruation and continuous vaginal spotting last three months accompanied with lower abdominal discomfort. Endometrial aspiration biopsy was performed because of suspicious endometrial pathology (em thickness was 14 mm), and the results revealed a well-differentiated adenocarcinoma.\nShe had been diagnosed with colon cancer 12 years earlier at the same institution and received a right hemicolectomy and chemotherapy. She had a family history of colon cancer. Her mother had colon cancer at the age of 56 years old, and her brother had colon cancer at the age of 48-year-old. Her family history was consistent with the clinical criteria for recommending genetic testing, i.e., at least three first-degree family members in two successive generations diagnosed with cancer before the age of 50-year-old. However, she was not provided genetic counseling at that time. According to the guidelines for genetic risk assessment of Lynch syndrome by the Society of Gynecologic Oncologists, patients have a 20% to 25% chance of developing cancer [].\nPreoperative cancer examinations were performed on biopsy samples, including genetic testing for microsatellite instability test (MSI) and mutations in MSH2 and MLH1.\nConsidering the age and family history of the patient, genetic counseling was provided, and genetic tests were performed. Two of her family members previously suffered from cancer (). Her mother had colon cancer at the age of 56 years old. Her older brother also had had colon cancer at the age of 48 years old.\nThe carcinoembryonic antigen concentration for the patient was 1.32 ng/mL, and CA-125 was normal.\nA 19-mm mass was observed in the endometrial cavity on a pelvic magnetic resonance imaging. There was no evidence of metastasis on the imaging test. In addition, washing cytology, total hysterectomy, bilateral salpingo-oophorectomy, and pelvic and paraaortic lymph node dissections were performed. Pathology results indicated a well-differentiated endometrioid adenocarcinoma (grade 1). Lymph vascular invasion was not observed (0/29).Washing cytology was negative.\nImmunohistochemistry (IHC) analysis showed that the endometrial tissue stained negative for MSH2 (). A MSI was performed and showed unstable final results (MSI-H; high microsatellite instability) (BAT25, BAT26, D2S123, and D5S346 were unstable, and D17S250 was stable). Loss of heterozygosity was not found in these markers.\nA mutation was detected at codon 629 in exon12 of MLH2, in which a glutamine was replaced by an arginine (1886A>G [p.Gln629Arg]) ().\nA colon biopsy obtained from the patient by colonoscopy was examined by IHC and found to be negative for MSH2 ().\nThe final diagnosis was stage IA endometrial cancer. No additional treatment was prescribed.