For patients returning to daily life following cancer treatment, managing body weight presents a secondary, formidable challenge. A South Korean study revealed that six out of ten cancer survivors who gain weight after surgery experience significant difficulty controlling it.
A research team led by Professors Shin Dongwook and Choi Healim of the Department of Family Medicine at Samsung Medical Center’s Cancer Survivorship Research Institute released findings on the 20th from a comprehensive survey of 2,024 patients. The study evaluated weight fluctuations and weight-management practices among survivors in their readjustment phase—defined as two months to two years post-cancer surgery. The findings were recently published in the international journal Cancer Medicine.
Compared to pre-diagnosis body weight, 36.8% of participants (744 patients) had lost weight, while 48.9% (990 patients) maintained stable body weight. The remaining 14.3% (290 patients) experienced weight gain. Post-treatment weight gain was particularly pronounced among working women under the age of 50, as well as patients treated for breast or gynecologic cancers.
The primary issue is that survivors who gained weight encountered far greater difficulty managing their health. The proportion of patients reporting that weight management was "not going well" stood at 29.6% in the weight-loss group and 30.1% in the weight-stable group, but surged to 63.5% among those who gained weight. Even after adjusting for age and comorbid conditions, unmet weight-management needs were 3.4 times higher in the weight-gain group compared to the weight-stable group.
The underlying reasons for weight-management difficulties varied according to the direction of weight change. Among patients who experienced weight loss, 40.5% reported that they "did not really know how to exercise or adjust their diet." Conversely, in the weight-gain group, the single most common barrier, cited by 40.2%, was that it was "hard to give up the pleasure of eating." Additionally, 26.6% reported a dislike of exercise, another 26.6% lacked knowledge on how to manage weight, and 23.9% cited treatment or medication side effects.
The researchers emphasized that while survivors who lost weight require targeted guidance on nutritional intake and exercise, those who gained weight need tailored behavioral support to manage appetite and dietary habits.
In fact, 54.8% of patients in the weight-gain group expressed willingness to participate in structured weight-management programs delivered through mobile applications or online platforms. Furthermore, roughly 40% stated they desired professional support from medical specialists at local clinics, community hospitals, or the tertiary hospital where they underwent cancer treatment.
"Cancer survivors who gain weight often appear to have recovered well and consequently receive less attention in clinical settings, yet they are actually experiencing the greatest difficulty," explained Professor Choi Healim. "Because weight gain following cancer treatment increases the long-term risk of cancer recurrence, secondary primary cancers, and cardiovascular or cerebrovascular diseases, it must be proactively managed from the moment acute treatment concludes."
"Female cancer survivors, in particular, frequently find it challenging to participate consistently in hospital-based programs while balancing career and family responsibilities, making digital weight-management services a practical, accessible alternative," Choi added.
Professor Shin Dongwook noted that pharmacotherapy could also serve as an effective clinical option for patients struggling with weight control.
"Obesity medications, such as glucagon-like peptide-1 (GLP-1) receptor agonists, may provide significant therapeutic benefit," Shin explained. "As emerging studies suggest potential clinical benefits not only for weight reduction but also for broader cancer outcomes, consulting a specialist is highly recommended."
