Devita, Hellman, and Rosenberg's Cancer

LWBK1006-45 LWW-Govindan-Review December 13, 2011 15:32

Chapter 45•Supportive Care and Quality of Life 569

Answer 45.13. The answer is A.

The patient has chronic postradiation brachial plexopathy. It is impor-

tant to recognize and effectively manage treatment-related chronic pain

syndromes, because these patients frequently need integrated approach to

treatment. Brachial plexus MRI is able to distinguish between tumor infil-

tration and radiation fibrosis. Radiation fibrosis injury typically produces

low signal intensity on T2-weighted images, generally not enhancing with

gadolinium.

Answer 45.14. The answer is D.

Although it is consoling to the patient to realize that her symptoms are not

related to recurrent cancer, the persistence of pain is a constant remainder

of the previous cancer diagnosis. Psychological factors play a significant

role in how these patients adapt to and function with chronic pain. A

multidisciplinary approach combining a wide range of therapies is usu-

ally needed. It is also very important to select appropriate analgesics for

neuropathic pain. Antidepressants and anticonvulsants will likely be most

effective. Antidepressant drugs should be first-line agents, given her tear-

fulness and anxiety.

Answer 45.15. The answer is D.

Approaches A to C are both reasonable options when dealing with a

patient with uncontrolled bone pain from prostate cancer. Opioid rotation

can also be attempted if tolerance to morphine is suspected. Methadone

can be considered, although conversion can be more challenging than

for other opioids because of prolonged plasma half-life but relatively

short duration of anesthesia. When converting from another opioid to

methadone, marked reduction in equianalgesic dose often results. A rea-

sonable starting methadone daily dose for this patient would be approx-

imately 30 mg of methadone divided into three doses (6:1 ratio for oral

morphine, based on 180 mg of oral morphine per day).

Answer 45.16. The answer is B.

All listed adverse effects can occur with opioids, but respiratory depres-

sion is unlikely in this setting. This adverse effect most commonly occurs

after a short course of intravenous administration of an opioid. Toler-

ance to this effect develops rapidly with repeat drug doses, which allows

prolonged use without significant risk of respiratory depression.

Answer 45.17. The answer is D.

Cost is one of the biggest advantages of methadone, which is relatively

inexpensive, compared with other opioids. Because of prolonged half-life,

it requires careful titration and may take up to 1 week to achieve steady

state. QT prolongation syndrome can occur with methadone and is a

cause for concern in those with cancer, who might be taking other agents,

known to prolong QT interval.