Screening and identification of Lynch syndrome: a systematic review of the frequency of Lynch syndrome-associated clinicopathologic and molecular characteristics in Lynch syndrome gynecologic cancers

Background This study aimed to investigate the frequency of Lynch syndrome-associated clinicopathologic and molecular characteristics in Lynch syndrome gynecologic cancers. Methods A systematic literature search was conducted in the literature databases (Medline, CINAHL, EMBASE, Google Scholar, Cochrane Library, and Clinicaltrials.gov) to identify the studies describing clinicopathologic characteristics, MMR protein immunohistochemistry and/or MSI, MLH1 methylation, and genetic testing in Lynch syndrome gynecologic cancer patients. Results A total of 24 of the evaluated studies that met the inclusion criteria were identified. A clinicopathological examination confirmed 242 endometrial cancer, 17 clear cells endometrial cancer, 35 serous endometrial cancer, 30 mixed and 21 other endometrial cancer. Thus, a total of 345 endometrial cancer was confirmed from the screening of 1,317 gynaecological cancer. However, the morphological analysis demonstrated 236 patients with endometrial cancer associated with Lynch syndrome. The frequency of confirmed LS with endometrial cancer was 68.40%. At diagnosis, the median age was 49.94±4.34 years, and the average BMI was 26.07±3.77 kg/m2. Endometrioid histology and stage I disease were the most frequent at 70.97% and 71.19% histological type and FIGO stage, respectively. Similarly, morphological and histological analysis demonstrated a higher degree of grade I cancer (47.28) and lymphovascular invasion (56.52%), respectively. Discussion Lynch syndrome-associated clinicopathologic and molecular characteristics occur significantly in Lynch syndrome gynecologic cancers and may improve risk stratification and triaging of gynecologic cancers for genetic testing.