Psyched Out

Chemo dosing key to ovarian cancer survival in obese women
Monday, January 05, 2009
DAVE PARKS
News staff writer

Adjusting chemotherapy doses so they are consistent with body weight appears to eliminate higher death rates that have been found among obese women with ovarian cancer, according to a new UAB study.

The study compared survival rates between obese and non-obese women with ovarian cancer.

Earlier studies had found that obese women with ovarian cancer were likely to have shorter survival times than non-obese patients with a similar type and stage of ovarian cancer.

The new study, which is being published in journal Gynocology Oncology, found no statistical difference between obese and non-obese patients who underwent similar surgeries and were given chemotherapy based on their body weight.

"Often chemotherapy dosing is calculated using ideal body weight as a guide," said Dr. Kellie Matthews, an OB/GYN at the University of Alabama at Birmingham and lead author of the study. "We found using actual body weight works best, and it wipes away much of the difference in survival rates between obese and non-obese patients."

Researchers looked at records from 304 patients diagnosed with an aggressive form of epithelial ovarian cancer, and showed that when actual body weight was used in chemotherapy dosing the overall survival was 40 months for non-obese patients and 47 months for obese patients - statistically identical rates when considering the relatively small size of the study.


This life-and-death medical need to dose by the actual woman's actual weight has been known for YEARS with respect to breast cancer. A cancer, I might add, that exists mostly in fat tissue, making dosing based on "ideal weight = lean mass content" less tenable in the first place. Even if muscle absorption vs. fat absorption differ, an ignorant guess/assumption that fat does not absorb chemo meds at all is uncalled for. Doctors persist in dosing fat women inaccurately, despite controlled, double blinded research showing that mis-dosing of chemo is both killing fat people and leading to the assumption that being fat, and not widespread malpractice, is why high weight is linked to cancer deaths.

And practicing medicine without basing it on sound existing science IS malpractice. Yet most med schools teach next to nothing about research and interpretation of it. The "science" classes involve identification of structure and function, a rote memorization of information, which has little to do with the complete scientific method.

Sigh.