Hereditary Polyposis Syndromes

Gardner syndrome

A subtype of FAP that includes extra-colonic manifestations such as osteomas and dental abnormalities.

Turcot syndrome type 2 (TS2)

A genetic syndrome associated with FAP and brain tumors.

Serrated polyposis syndrome

Characterized by serrated polyps in the colon, increasing colorectal cancer risk.

Lynch syndrome

Also known as hereditary nonpolyposis colorectal cancer (HNPCC), it significantly increases the risk of colorectal and other cancers.

APC gene

A tumor suppressor gene that, when mutated, is responsible for familial adenomatous polyposis.

Genotype-phenotype correlation

The relationship between specific genetic mutations and the resulting physical traits or disease symptoms.

Anastomosis

The surgical connection between two structures, often performed after removal of a part of the intestine.

Endoscopic evaluation

A procedure that uses a flexible tube to examine the gastrointestinal tract and potentially remove polyps.

Surveillance colonoscopy

Regular screening method used to monitor for polyps and cancer in patients with polyposis syndromes.

Surgical options for treating FAP

Includes total abdominal colectomy and proctocolectomy with ileal pouch-anal anastomosis.

Lifetime cancer risk for PJS

Patients have a lifetime risk of cancer as high as 83%, including gastrointestinal and breast cancers.

Upper endoscopy

An examination of the upper gastrointestinal tract using an endoscope, often used for surveillance in PJS.

Ileorectal anastomosis (IRA)

A surgical procedure connecting the ileum directly to the rectum, often performed after colectomy.

Hereditary gastrointestinal polyposis syndromes

Adenomatous and hamartomatous types

adenomatous

FAP, AFAP, Gardner syndrome, TS2, GAPPS, MAP, serrated polyposis

hamartomatous

Peutz-Jeghers syndrome, familial juvenile polyposis

Familial adenomatous polyposis (FAP)

Mutations in APC, development of <100 polyps in the colon and rectum.

FAP risks

up to 100% chance of CRC if untreated; stomach, small intestine, pancreas, biliary tract, hepatoblastoma, thyroid

FAP onset

mid-teens, usually multiple polyps by 35

FAP non-cancerous findings

osteomas, extra/missing teeth, desmoid tumors, congenital hypertrophy of retinal pigment epithelium (CHRPE), skin changes, adrenal masses

FAP management

annual colonoscopy starting at 10-15, surgery once poly burden is too much, upper endoscopy at 20-25, baseline thyroid exam, abdominal palpation

Attenuated familial adenomatous polyposis (AFAP)

A variant of FAP characterized by fewer polyps and later onset of colorectal cancer.

AFAP management

screening in late teens, colectomy with increased polyp burden, upper endoscopy, baseline thyroid

Peutz-Jeghers syndrome (PJS)

AD; mutations in STK11 lead to gastrointestinal polyps and mucocutaneous pigmentation.

PJS penetrance

close to 100%

PJS clinical symptoms

dark skin freckling, PJS polyps, adenomas

PJS risks

as high as 83% lifetime risk; GI, breast, cervical, uterine, pancreatic, lung, benign ovarian tumors

PJS surveillance (pediatric)

upper endoscopy and colonoscopy (8-10), annual testicular exam (10), small bowel visualization (8-10)

PJS surveillance (adults)

mammogram at 30, colonscopy at 18, upper endoscopy at 18, pancreatic screening at 30-35