GI Malignancies

Question 1

What are some monoclonals for tx of colorectal cancer?

Answer 1

bevacizumab and cetuximab

Question 2

How common is CRC?

Answer 2

3rd most common cancer and 2nd most deadly with 20% of pts having METs at diagnosis

Question 3

What is the tx of CRC?

Answer 3

5-FU + leucovorin + oxplatin (aka FOLFOX), or irinotecan instead of oxplatin (aka FOLFIRI)

Question 4

When are Bevacizumab and cetuximab not helpful in tx of CRC?

Answer 4

in the presence of KRAS mutations (down stream of action)

Question 5

What does Bevacizumab do?

Answer 5

Bevacizumab is a recombinant humanized monoclonal antibody that blocks angiogenesis by inhibiting vascular endothelial growth factor A(VEGF-A)

Question 6

What is Cetuximab?

Answer 6

Cetuximab (INN) is an epidermal growth factor receptor (EGFR) inhibitor used for the treatment of metastatic colorectal cancer, and others

Question 7

How is anal cancer tx?

Answer 7

Radiation therpay alone may lead to a 5-yr survival rate in excess of 70%, and added cisplatin, 5-FU, or mitomycin may help

Question 8

How common is gastric cancer?

Answer 8

4th most deadly cancer with a 5-yr survival of 20%

Question 9

All gastric cancer pts should be tested for what?

Answer 9

All should be tested for HER-2 (add trastuzumab to the standard 5-FU/cisplatin regimen if positive)

Question 10

What else can be used to tx gastric cancer?

Answer 10

glutamic acid, which acts as a gatric acidifer to counterbalance deficiencies in HCl

Question 11

What are three tx options for GI carcinoid tumors?

Answer 11

• octreotide
• methysergide
• IFN-a

Question 12

Why is octerotide helpful in GI carcinoid tumors?

Answer 12

It acts at somatostatin receptors to inhibit the secretion of serotonin and other peptides, which results in:

increased intestinal absorption of water and electrolytes,

decreased gastric acid secretions, and

increased intestinal transit time

Question 13

How long can octreotide typically be used to tx GI carcinoid tumors?

Answer 13

12 months due to tachyphylaxis

Question 14

How does methylsergide help in tx of GI carcinoid tumors?

Answer 14

it is a serotonin antagonist that can be used to inhibit diarrhea arising

Question 15

IFN-a inhibits disease progression and provides symptom relief in 75% of pts. but is limited by its AEs. Name some

Answer 15

• alopecia
• anorexia
• fatigue and fever
• weight loss
• myelosuppression

Question 16

What are the main mutational types of GISTs?

Answer 16

80% KIT mutant

5% KIT negative

5-8% PDGFRA mutant

12-15% wild type

Question 17

Note that for GISTs, conventional cytotoxic chemo is essentially futile, partly due to P-gp overexpression

Question 18

What are two tx options for GISTs?

Answer 18

• Imatinib mesylate
• Sunitinib malate

Question 19

What is the 1st line tx of unresectable, metastatis, or recurrent GIST?

Answer 19

Imatinib (Sunitinib is reserved for those unresponsive to Imatinib tx)

Question 20

What is a TKI used in tx of pancreatic cancer?

Answer 20

Erlotinib

Question 21

What are the tx options for pacnreatic cancer?

Answer 21

Gemcitabine or 5-FU/folinic acid

Gemcitabine and erlotinib or FLOFIRINOX

Question 22

80% of cases of liver cancer are associated with what?

Answer 22

HBV or HCV infections, which can directly interact with signaling pathways that promote cellular proliferation

Question 23

What are some main tx options for liver cancer?

Answer 23

TACE, trans-catheter arterial chemoembolization

-Sorafenib

Question 24

Describe TACE, trans-catheter arterial chemoembolization

Answer 24

Doxorubicin is injected while the hepatic a. branch feeding the tumor is occluded with an embolic agent (spares normal tissue an limits dispersion)

Question 25

What is considered the standard of care for liver cancer pts with advanced HCC?

Answer 25

Sorafenib

Question 26

How does Sorafenib work?

Answer 26

Sorafenib is a small inhibitor of several tyrosine protein kinases, such as VEGFR, PDGFR and Raf family kinases (more avidly C-Raf than B-Raf)