LWBK1006-08 LWW-Govindan-Review December 12, 2011 18:49
Chapter 8•Principles of Medical Oncology 101Answer 8.8. The answer is C.
Activation of caspases leads to cell death, whereas activation of Bcl-2,
Bcl-xL, and NF-B lead to inhibition of apoptosis.Answer 8.9. The answer is C.
The most important indicator of the effectiveness of chemotherapy is
the rate of complete response. Despite improvements in response rates
and overall survival in certain metastatic diseases, unless a complete
response is achieved with chemotherapy, the patient is not considered
cured.Answer 8.10. The answer is A.
A partial response is defined as at least a 50% improvement in measur-
able tumor mass. Although there are data to suggest that quality of life
and survival may improve when a partial response is achieved, these are
qualitative measures.Answer 8.11. The answer is A.
Bortezomib exerts its anticancer activity by inhibiting the 26S protea-
some. The proteasome–ubiquitin complex degrades several intracellular
regulatory proteins including IB that is an inhibitor of NFB. Activation
of NFB promotes cell proliferation and inhibition of apoptosis.Answer 8.12. The answer is B.
The majority of relapses in early-stage colon cancer treated with adjuvant
chemotherapy occur within the first 3 years. Therefore, adjuvant trials
may use 3-year disease-free survival as the primary end point.Answer 8.13. The answer is D.
Gompertzian kinetics provides a model of tumor growth whereby the
growth fraction of a tumor decreases exponentially over time. Clini-
cally undetectable tumors are at their highest growth fraction. There-
fore, chemotherapy would result in a significantly higher fractional cell
kill.Answer 8.14. The answer is D.
T790M mutation and MET gene amplification are the common causes for
development of resistance to EGFR TKIs such as gefitinib and erlotinib
in patients with activating mutations in the TK domain of the EGFR
gene. In addition, loss of PTEN expression and D761Y mutation has
been implicated in the development of resistance to EGFR TKI.Answer 8.15. The answer is D.
Reinitiation of the original induction chemotherapeutic agent is possible
if there is a good response.