Intestinal Neoplasia Flashcards
Where do neuroendocrine tumors originate and how quickly to they grow?
arise from cell with neuroendocrine differentiation
GI carcinoid tumors are often slow growing and arise from Kulchitsky cells
(women and white folks with more lung tumors)
What are risk factors for development of NET?
Genetic syndromes including:
MEN-1
von Hippel-Lindau (kidney)
Neurofibromatosis
Describe the histopathology of NET?
heavily vascularized tumors with salt and pepper chromatin, usually with trabeculations within the storm
What is the presentation of NET?
often asymptomatic, vague abdominal pain and poor appetite is possible
What are the endocrine syndromes that result from insulinoma, glucagonoma, somatostatinoma and gastronome?
insulinoma: hypoglycemia (within inappropriately high insulin)
glucagonoma: hyperglycemia, specific skin rash
somatostatinoma: zollinger-ellison
Gastrinoma: lots and lots of gastric ulcers, GI bleeding
What are the three classic symptoms of carcinoid tumor?
flushing (triggered by stress, amine rich food and alcohol)
watery diarrhea
wheezing/bronchospasm
palpitations/right sided heart disease due to tricuspid regurgitation
may also cause obstruction or intentional angina
Many NET, carcinoid especially, produce serotonin, how can this be used to diagnosis carcinoid tumor? What imaging might be used to confirm?
because serotonin is broken down into water would form for urinary excretion you must complete a 24 urine collection and measure 5-HIAA (can be affected by foods like avocados, walnuts)
*note chromogranin can also be elevated by sensitivity and specificity are 80-90%, can be elevated in hepatic or renal insufficiency
for dx/staging: CT scan with contrast (timing of contrast again), MRI with contrast, octerotide nuclear medication (not definitive)
How likely are NET to metastasize?
grade 1 tumors rarely metastasize at diagnosis, while grade 3 which are poorly differentiated, nearly 50% are dx with metastatic disease
Which is more important in NET prognosis: grade or staging?
grade is more predictive including:
mitotic count
proliferative index is measured by K1-67
What is the standard tx. of NET?
surgical resection is the gold standard, depending on the primary location and the extent of surgery depends on risk of recurrence
intestinal NET: appendectomy with R. hemicolectomy, unless tumor <1cm (appendectomy alone is OK)
pancreatic NET: whipple
bronchial carcinoid: lobectomy
What role does ablation or chemotherapy have in NET treatment?
ablation used primarily for symptomatic tumors akin to debulking
chemotherapy used for higher grade tumors, consider chemo+ radiation , low grade tumors are often chemotherapy resistant
How does octreotide effect disease progression in NET?
used for symptomatic release (diarrhea and flushing) but has also been shown to slow progression of disease
What is the primary risk factor/causative factor for MALToma?
chronic infection with H. pylori; chronic inflammation leads to lymphocytic proliferation (tissue and staining for H. pylori is required for dx)
eradication of H. pylori can cause tumors to regress
What factors of MALToma would cause a higher risk of relapse?
extra intestinal lymph node involvement
high grade features
H. pylori negativity
What lymphomas beside MALToma are likely in the intestine?
mantle cell lymphoma (bad prognosis)
follicular lymphoma
treatment for different types of hematologic malignancies in the intestine is different so biopsy is important
