[Jackie07]

This recent research article cautions against the risk of lymphedema [I walked 30 minutes everyday during chemo - probably had some detox effect (from sweating) besides other benefits.]:

Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA.
Lifestyle risk factors associated with arm swelling among women with breast cancer.
Showalter SL, Brown JC, Cheville AL, Fisher CS, Sataloff D, Schmitz KH.
Ann Surg Oncol. 2013 Mar;20(3):842-9. doi: 10.1245/s10434-012-2631-9. Epub 2012 Oct 3.
Abstract

BACKGROUND:
Breast cancer-related lymphedema (BCRL) is a feared complication for breast cancer patients who have undergone axillary surgery. Although clinical risk factors for BCRL are defined, data are sparse regarding common exposures that might induce incident arm swelling. The goal of this study was to quantify the association between common exposures thought to be potential risk factors and the occurrence of incident arm swelling among breast cancer survivors with or at risk for BCRL.

METHODS:
This is a prospective subanalysis of the Physical Activity and Lymphedema (PAL) trial, a randomized controlled trial of 295 breast cancersurvivors. Participants reported their exposure to 30 different potential risk factors at 3 month intervals for 1 year. Incident arm swelling was defined as a ≥5% increase in interlimb water volume difference between two consecutive time points.

RESULTS:
Twenty-seven participants (9%) experienced incident arm swelling and 268 patients (91%) did not. Sauna use was the only exposure that was significantly predictive of incident arm swelling (p = 0.05). Nonwhite and nonblack participants had a significantly increased risk for experiencing incident arm swelling (p = 0.005 for both comparisons).

CONCLUSIONS:
In our patient cohort, many common exposures that have been reported to be risk factors did not prove to have a significant predictive relationship for incident arm swelling. This study supports the recommendation that breast cancer patients who have had axillary surgery should avoid sauna use. The results do not confirm the need for other restrictions that may interfere with the quality of life in women with breastcancer.