(NCI, ACS, National Lymphedema Network, Susan G. Komen Foundation) include recommendations to breast cancer survivors to avoid ever lifting anything heavier than 5 to 15 pounds. This recommendation has negative health promotion and quality of life implications. According to the AHRQ review, “There is too little research on this topic thus far to appropriately and safely prescribe physical activity for breast cancer survivors at risk for (or with a diagnosis of) lymphedema.” Further research on this topic is needed to guide the more than 2 million American breast cancer survivors.
There is an additional concern that too-vigorous physical activity could depress the immune system and promote the spread of cancer. In generally healthy adults, moderate-intensity physical activity is associated with overall improvement in immune parameters, while high-intensity, high-volume physical activity is associated with a temporary worsening of immune function. According to the AHRQ review, additional studies are needed to clarify the effects on certain immune parameters, with specificity as to timing across the cancer experience as well as physical activity mode, frequency, intensity, and duration (Holtzman et al., 2004).
There is limited evidence regarding the extent to which physicians are providing guidance regarding exercise to their patients who are cancer survivors. According to two relatively large surveys, 20 to 35 percent of cancer survivors reported that their physician recommended changes in their exercise behavior. One study included a sample of cancer survivors with several types of cancer (Blanchard et al., 2003a) while the other study was limited to survivors of breast and prostate cancer (Demark-Wahnefried et al., 2000). An oncologist’s recommendation to exercise may increase exercise behavior, according to a randomized trial that involved breast cancer survivors (Jones et al., 2004). One study suggests that cancer survivors prefer that their oncologist initiate a discussion about exercise (Jones and Courneya, 2002).
A framework for examining physical activity across the cancer experience (Framework PEACE) has been proposed based on the cancer control perspective (Courneya and Friedenreich, 2001). The framework includes six possible cancer control outcomes after the point of cancer diagnosis, including buffering prior to treatment (i.e., building up physical condition before treatment), coping during treatment, rehabilitation immediately after treatment, health promotion and survival for those with positive treatment outcomes, and palliation for those without positive treatment outcomes. The AHRQ review concludes that additional research is needed on the effects of physical activity on pretreatment outcomes, health promotion, survival, and palliation.