Colorectal cancers

What are 3 gene mutations associated with colorectal cancer?

APC tumor suppressor gene

p53 tumor suppressor gene

K-ras oncogene

are these types of polyps malignant potential or no?

hyperplastic and inflammatory

not usually malignant potential

are these types of polyps malignant potential or no?

adenomatous (tubular, tubulovillous, villous)

yes malignant potential

What are the 4 things that make an adenoma advanced?

large size, villous features, high grade dysplasia, and 3+ synchronous adenomas (meaning 3+ at the same time)

What method for screening of colorectal cancer identifies hemoglobin in the stool by the presence of a peroxidase reaction

FIT (fecal immunochemical testing for blood)

what are the DNA tests for colorectal cancer?

multi-targeted stool DNA (cologard) and cell free DNA (shield)

what screening for colorectal cancer reaches the splenic flexure and no prep needed, just enemas

flexible sigmoidoscopy

what is the gold standard for colorectal cancer screening?

colonoscopy

What is a reconstruction of the colon that is diagnostic not therapeutic and requires bowel prep?

CT colography

When should people get a colonoscopy?

beginning at 45 and every 10 years

Explain the TNM staging of colorectal cancer

T: depth

N: lymph node involvement

M: metastases to other organs

what are the 4 main treatments of colorectal cancer?

surgery, chemo, radiation (mostly done for rectal cancer), and palliation (relieve sx like helping an obstructed bowel that was obstructed by tumors)

What syndrome?

group of conditions associated with multiple luminal GI polpys

polyposis syndrome

What syndrome?

hundreds to thousands of colonic adenomatous polyps, colon cancer is inevitable, mutations in APC gene

familial adenomatous polyposis (FAP)

What syndrome?

presence of at least 100 adenomatous colonic polyps OR fewer polyps and an immediate family relative with the syndrome

familial adenomatous polyposis (FAP)

how do we treat FAP?

total colectomy

What syndrome?

we can see osteomas, dental abnormalities, cutaneous lesions, desmoid tumors, or congenital hypertrophy of the retinal pigment epithelium (CHRPE)

FAP- familial adenomatous polyposis

What syndrome?
fewer polyps (less than 100), later onset of cancer, and located in proximal colon

attenuated familial adenomatous polyposis (AFAP)

basically a toned down version of FAP

What FAP variant?

very prominent extra-intestinal manifestations, extra teeth, and non-cancerous lesions in the bone and skin

Gardner syndrome

What FAP variant?

associated with medulloblastoma, anaplastic astrocytoma, ependymoma, or glioblastoma multiforme

Turcot syndrome

What syndrome?

DNA mismatch repair (MLH1, MSH2, MSH6, PMS2)

Lynch syndrome

What syndrome?

early onset of colorectal cancer and increased risk of extracolonic malignancy (like uterus, ovarian, stomach, small bowel, and biliary)

Lynch syndrome

What syndrome?

the adenoma to carcinoma sequence occurs more rapidly (2-3 years rather than around 5 years)

Lynch syndrome

What syndrome?

associated with sebaceous neoplasms

Muir-Torre syndrome

What syndrome?

multiple hamartomatous polyps scattered throughout GI tract and melanin deposits in lips, gums, face, genitals, hands and feet

Peutz-Jeghers syndrome