ASCO Genitourinary Cancers Symposium (Interim analysis of carbohydrate restriction for men with a rising PSA after failed primary treatment)

[pjoshea13]

Our old friend Steve Freedland.

"Men had to have a BMI >=24 kg/m2, received radical prostatectomy or definitive local radiation for PC, had a PSA 0.4-20.0 ng/ml (3-20 if prior radiation therapy) within the past 3 months, and current PSADT 3-36 months. The intervention arm was instructed to eat , 20 grams/carbs/day with no other limits."

Eat all you want but not carbs.

"Six months on the low carb diet resulted in greater weight loss (median: 31.7 vs. 0.8 lbs"

"Whether this weight loss slows PC growth is an on-going question."

My guess is that weight loss will slow PCa, since there must be a score of studies that associate high BMI with aggressive disease & faster progression.

The men did eat more fat, but the biggest increase was in protein (125 vs. 73 g), which I doubt is a good idea.

-Patrick

382 Poster Session (Board #F7), Fri, 12:15 PM-1:45 PM and

6:00 PM-7:00 PM

Interim analysis of a prospective randomized trial of dietary carbohydrate restriction for men with a rising PSA after failed primary treatment: Carbohydrate and Prostate Study 2 (CAPS2).

Stephen J. Freedland, Jenifer Allen, Andrew J. Armstrong, Judd W. Moul, Howard M. Sandler, Dana Levin, Lauren E. Howard, Pao-hwa Lin; Cedars-Sinai Medical Center, Los Angeles, CA; Duke University, Durham, NC; Duke Cancer Institute, Duke University, Durham, NC; Cedars-Sinai, Los Angeles, CA; Durham VA Medical Center/ Duke University, Durham, NC

Background: Nearly one third of men treated with curative intent for localized prostate cancer (PC) will develop a rising PSA. The rate of PSA rise (PSA doubling time aka PSASDT) is a predictor metastases and PC death. In laboratory mice, an extreme low carbohydrate diet slows PC growth. We tested whether this diet could slow PSADT in men with recurrent PC.

Methods: We are conducting a 6-month multi-center randomized phase II trial of dietary carbohydrate restriction vs. no diet intervention control. Men had to have a BMI $24 kg/m2, received radical prostatectomy or definitive local radiation for PC, had a PSA 0.4-20.0 ng/ml (3-20 if prior radiation therapy) within the past 3 months, and current PSADT 3-36 months. The intervention arm was instructed to eat , 20 grams/carbs/day with no other limits. The control arm was told to make no diet. In this interim analysis, we present the efficacy of the dietary intervention with regards to weight loss. Arms were compared using rank-sum. Total anticipated enrollment is 60. The primary outcome is differences in PSADT between arms. Secondary outcomes include weight loss, and dietary make-up.

Results: To date, 28 patients (14 in each study arm) have completed the study. Characteristics were well- balanced at baseline. At the 6-month dietary assessment, calorie consumption was similar between the two study arms (p = 0.090) among the 16 patients (7 low-carb, 9 control) with diet information. Subjects in the low-carb arm ate fewer carbs (29 vs. 188 g, p = 0.008) and more protein (125 vs. 73 g, p = 0.044) but similar amounts of fat (75 vs. 67 g, p = 0.672) vs. subjects in the control arm. Six months on the low carb diet resulted in greater weight loss (median: 31.7 vs. 0.8 lbs, p , 0.001), lower BMI (24.4 vs. 29.6 kg/m2, p , 0.001), and smaller waist circumference (95.7 vs. 108.9 cm, p = 0.002).

Conclusions: In this interim analysis of an on-going dietary study for men with a rising PSA after definitive local treatment, an extreme low carbohydrate diet results in dramatic weight loss in 6 months. Whether this weight loss slows PC growth is an on-going question. Clinical trial information: NCT01763944.

[herb1]

HI PJ: I've been keeping fairly close nutrition records since my triple bypass. The recommended values are 335 gm of carbo in a diet of 2250 cal. My typical intake is maybe 75-90% of recommended. Getting down to 25 gm carbo sounds near impossible in real life; the carbo content of most SINGLE foods is ~25 gm/serving. Yes, I have not lost weight, but I am [trying to] live my life WHILE fighting PCA, obesity, heart disease, etc. What I"m suggesting: is it worth it, even if it works?

Further, the range of qualifying factors seems very broad, suggesting that almost anyone would lose weight under this regime. Is that healthy? probably. Is it worth it?

[jimk_mb]

20 gm of carbs per day = only 80 kcal of carbs for the whole day! Sounds pretty extreme. Be interesting to see how many grams of protein and fat their typical participant ended up eating. May not be very heart or kidney healthy.

Separately, thank you for digesting and reporting on all the ASCO Genitourinary papers. Much appreciated.