Devita, Hellman, and Rosenberg's Cancer

LWBK1006-15 LWW-Govindan-Review December 7, 2011 19:5

170 DeVita, Hellman, and Rosenberg’s CANCER: Principles and Practice of Oncology Review

ANSWERS

Answer 15.1. The answer is A.

Patients with KRAS mutation in codons 12 or 13 have low probability of

achieving benefit from anti-EGFR antibodies and should not receive these

drugs. CEA is not recommended in the screening of colorectal cancer but

is valuable in the postsurgical surveillance and for monitoring metastatic

disease during systemic therapy. MSI is not recommended to determine

the prognosis or efficacy from adjuvant chemotherapy.

Answer 15.2. The answer is C.

The presence of tissue CDX2 suggests the diagnosis of colon cancer.

Answer 15.3. The answer is A.

Patients withUGTA1Adeficiency are unable to metabolize irinotecan

with increased risk for significant toxicity. The risk of toxicity from

5-fluorouracil or capecitabine is increased in patients with dihydropy-

rimidine dehydrogenase deficiency.

Answer 15.4. The answer is B.

Infection is significantly more common in tunneled catheters with exter-

nalized hubs than in implanted subcutaneous devices.

Answer 15.5. The answer is D.

Inability to clear the infection with antibiotic therapy, continued bac-

teremia, and recurrent infection after treatment completion are all

indications for catheter removal.

Answer 15.6. The answer is D.

Percutaneous thermal ablation of lung cancer is a relatively new technique

that uses CT guidance to place a probe within a lung neoplasm. This probe

is then used to deliver targeted thermal therapy. Studies are under way

to determine how this technique compares with more well-established

therapies. The procedure is performed under conscious sedation and can

usually be completed within 1 hour. Efficacy is predominantly based on

the volume of the lesion and the location. Accessible lesions less than 3 cm

are likely to completely respond. Complications include hemorrhage,

infection, and pneumothorax. The first two are unusual if sterile technique

is used and any coagulopathy is corrected before beginning. Pneumotho-

rax may be seen in 25% to 40% of patients undergoing ablation.

Answer 15.7. The answer is C.

As with lung biopsies, preprocedural imaging is important in determining

the route of approach and type of needles to be used for percutaneous

abdominal and pelvic biopsies. Certain organs, because of their most