Supplementary Material for: Endometrial cancer diagnosed at an early stage during Lynch syndrome surveillance: a case report

Lynch syndrome is an autosomal dominant inherited disorder caused by a germline pathogenic variant in DNA mismatch repair genes, resulting in multi-organ cancer. Annual transvaginal ultrasonography and endometrial biopsy are recommended for endometrial cancer surveillance in patients with Lynch syndrome in several guidelines; however, evidence is limited. Here, we present the case of a 51-year-old woman with endometrial cancer who underwent robot-assisted laparoscopic simple hysterectomy at an early stage detected by Lynch syndrome surveillance. The patient was a 51-year-old gravida 0 woman without any medical history or symptoms. Her sister suffered from bladder, breast, rectal, and endometrial cancer and was diagnosed with Lynch syndrome using a hereditary cancer panel test (VistaSeq®︎). During gynecologic surveillance, the patient’s endometrial cytology was suspected to be malignant. Therefore, she underwent endometrial curettage with hysteroscopy and was diagnosed with atypical endometrial hyperplasia. Robot-assisted hysterectomy was performed with a final pathological diagnosis of endometrial cancer (endometrioid carcinoma, Grade 1), stage 1A. She has remained disease-free for more than 12 months. Due to advances in genetic medicine, prophylactic and therapeutic surgeries for hereditary cancers are increasing. To achieve an early diagnosis and treatment of Lynch syndrome-associated cancers, the importance of Lynch syndrome surveillance should be more widely recognized.