Taylor D Coleman, MD, Christine Tat, MD, Joaquin Estrada, MD, FACS, Jan Kaminski, MD, FACS. University of Illinois, Metropolitan Group Hospitals
Colorectal carcinoma (CRC) is the most common malignancy of the GI tract. Many molecular mechanisms underlying development remain unknown. Our case presents a rare genetic condition, FG Syndrome, with numerous genes on the X chromosome that have been found to be associated with increased risk for progression to CRC. Our patient, a 32-year-old male with FG Syndrome, intellectual disability, schizo-affective disorder, imperforate anus originally presented with constipation, abdominal pain, and intermittent rectal bleeding. Work-up revealed a fungating, obstructing mass at the sigmoid colon with biopsy consistent with adenocarcinoma. The patient underwent a combined laparoscopic left segmental colectomy with primary anastomosis as well as an open partial hepatectomy. Pathology was consistent with a pT3N2aM1a lesion.
Although CRC can be most commonly associated with a variety of genetic, environmental, and dietary factors, this report will focus on its association with FG Syndrome. Most mutations that lead to FG syndrome involve the MED12 gene, though it is important to note there are numerous genes associated with the syndrome’s various presentations. These genes include Mecp2, CASK, and FLNA. In a patient with a genetically predisposed syndrome, who then develops CRC at an early age, it is reasonable to suspect that the explanation may be found at the genetic level. Variations in expression of these aforementioned genes have been shown to be, 1. Risk factors for the development of CRC, and 2. Prognostic factors after the diagnosis of CRC.
When evaluating our patient who has presented with newly diagnosed CRC at a young age, a work up is completed that includes testing for some of the more common causes of genetically associated predisposition to the development of this malignancy. Testing included Microsatellite Instability/HNPCC work up which showed microsatellite stable tumor. Another test screened for a pathogenic variant of RAS mutation including KRAS and NRAS. There was no pathogenic variant detected. These results leave us raising questions in need of further investigation, such as “do the mutations associated with FG Syndrome have a causative effect or prognostic function in the disease process?” “Which of these mutations could provide a possible screening test for these patients in the future?” “Would patients with FG syndrome benefit from early screening for CRC?” Although FG Syndrome is a rare condition, the ideas and questions discussed in this paper can be applied far past the narrow spectrum of this one disorder.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 95671
Program Number: P351
Presentation Session: Poster Session (Non CME)
Presentation Type: Poster