title: Lower gastrointestinal neuroendocrine neoplasms associated with hereditary cancer syndromes: a case series.
abstract: Lower gastrointestinal (GI) neuroendocrine neoplasms (NENs) of the colon and rectum are uncommon and not traditionally associated with hereditary GI cancer syndromes. However, with widespread implementation of colorectal cancer screening programs, lower GI NENs are being identified with increasing frequency. We report the first case series of six patients with lower GI NENs who were diagnosed with hereditary GI cancer syndromes by germline testing. Two patients presented with poorly differentiated rectal neuroendocrine carcinoma (NECs) with colonic polyposis and were found to have Familial Adenomatous Polyposis and MYH-Associated Polyposis, respectively. Three patients with colorectal NENs (one well differentiated neuroendocrine tumor, NET, and two NECs), all of which displayed abnormal immunohistochemistry for mismatch repair proteins, were diagnosed with Lynch syndrome. One patient with a goblet cell carcinoid was diagnosed with CHEK2 mutations. All patients met genetic testing guidelines and the diagnosis was made utilizing next generation sequencing gene panel tests. Lower GI NETs should therefore be considered a potential hereditary GI cancer syndrome-associated malignancy in patients who otherwise meet criteria for genetic evaluation.
authors.affiliation: Division of Gastroenterology, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Trilokesh D
authors.initials: TD
authors.lastname: Kidambi
authors.affiliation: Hereditary GI Cancer Prevention Program, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Pedley
authors.affiliation: Hereditary GI Cancer Prevention Program, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Amie
authors.initials: A
authors.lastname: Blanco
authors.affiliation: Hereditary GI Cancer Prevention Program, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA.|Division of Medical Oncology, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Emily K
authors.initials: EK
authors.lastname: Bergsland
authors.affiliation: Division of Gastroenterology, University of California, San Francisco, San Francisco, CA, USA. Jonathan.Terdiman@ucsf.edu.|Hereditary GI Cancer Prevention Program, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA. Jonathan.Terdiman@ucsf.edu.|Clinical Medicine and Surgery, University of California, San Francisco, 1701 Divisadero, San Francisco, CA, 94115, USA. Jonathan.Terdiman@ucsf.edu.
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Terdiman
mesh_terms: D011125:Adenomatous Polyposis Coli / Q000235:genetics; D000328:Adult; D064447:Checkpoint Kinase 2 / Q000235:genetics; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000235:genetics / Q000473:pathology / Q000628:therapy; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000235:genetics* / Q000473:pathology / Q000628:therapy; D005817:Genetic Counseling; D018095:Germ-Line Mutation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009386:Neoplastic Syndromes, Hereditary / Q000235:genetics / Q000473:pathology; D018358:Neuroendocrine Tumors / Q000235:genetics* / Q000473:pathology / Q000628:therapy
chemical_list: D064447:Checkpoint Kinase 2; C578634:CHEK2 protein, human
keywords: Hereditary colon cancer; Lynch syndrome; Neuroendocrine tumor; Polyposis