MKSAP Quiz: Advice before beginning chemotherapy regimen
A 73-year-old woman seeks advice before beginning a new chemotherapy regimen for metastatic adenocarcinoma of the colon. What can the patient reasonably expect with the new chemotherapy regimen?
A 73-year-old woman seeks advice before beginning a new chemotherapy regimen for metastatic adenocarcinoma of the colon. The new chemotherapy protocol has a modest progression-free survival benefit over a placebo but with increased toxicity. She is currently feeling well, has minor tumor pain controlled with occasional use of ibuprofen, and continues to work full time.
Which of the following results can the patient reasonably expect with the new chemotherapy regimen?
A. Greater probability of cure
B. Improved quality of life
C. Longer life
D. Longer time without further cancer growth
MKSAP Answer and Critique
The correct answer is D. Longer time without further cancer growth. This content is available to MKSAP 19 subscribers as Question 47 in the Oncology section. More information about MKSAP is available online.
A longer time without further cancer growth (Option D) can be most reasonably expected with this patient's new chemotherapy regimen. Progression-free survival is a metric characterized as the time from when a treatment is started until the time that either the tumor progresses or the patient dies. It is therefore a measure of how long the patient will live with the disease under control, but it is not a measure of how long the patient will live (Option C). Progression-free survival is a term that is easily misunderstood and confused with overall survival. Progression-free interval would more accurately describe what is referred to as progression-free survival.
The one pure and simple term is cure (Option A). Cure means, as one would expect, that the cancer is gone, no further treatment is required, and the patient will live out his or her life without seeing that type of cancer again. This should not be confused with overall survival. Overall survival is the term used to describe the time from when a treatment is started until the time of patient death, and so it is a metric of how long a patient lived. Overall survival is often misunderstood by patients to be synonymous with cure. This misunderstanding can be further compounded by the frequent use of the phrase significant improvement in survival, in which significant refers to the statistical certainty of the finding but is often misinterpreted as a substantial improvement in survival. Many drugs have been approved with significant improvements in survival that are limited to less than 2 or 3 months, a quantity that may not be clinically significant.
Quality of life (Option B) is a complex metric that incorporates many physical and psychological aspects of a patient's overall condition. However, in a patient with low symptom burden such as the one described here, a drug that has added toxicity is unlikely to contribute favorably to quality of life.
Key Point
- Progression-free survival is the time from when a treatment is started until that treatment is no longer controlling the cancer; progression-free survival may not correlate with overall survival.