Endocrine disorders are common in people who received cancer treatment in childhood and adulthood, especially as life expectancy in these patients continues to rise with the advance of these treatments, according to a paper recently published in Endocrine Reviews.
The review, by Judith Gebauer, of the University Hospital of Schleswig-Holstein in Luebeck, Germany, points out that therapy-related late effects of cancer treatment have become increasingly recognized in during the past 20 years, and that endocrine disorders are among the most frequent of these effects. Children are more susceptible than adults, and up to 50% of long-term childhood cancer survivors will develop an endocrine disorder. “The risk for the development of late effects critically depends on the oncological treatment regimen used,” the authors write. “Details of these regimens have been applied to predict the individual risk for certain long-term sequelae and form the basis for the structured lifelong surveillance suggested by various international guidelines.”
According to the authors, most data are based on the late effects of treatment in former childhood cancer patients for whom specific guidelines and recommendations already exist, but the data on the effects of in adults is not as robust. Surveillance of adults who develop cancer ends after those patients see five years of no recurrence of their cancer. And since the likelihood of developing cancer increases with age, adults who develop cancer later in life won’t live as long even if their cancer is successfully treated. However, life expectancy is increasing overall, which means more and more adult cancer survivors are experiencing late complications from their cancer treatment.
The authors then detail the mechanisms by which various therapies affect the endocrine system: radiotherapy can damage cells and DNA, affecting endocrine organs like the thyroid and pituitary gland, while chemotherapy can contribute to oxidative stress and tissue damage, for example. Cancer treatments can even lead to further malignancies in the thyroid and other endocrine organs.
The increasing success of cancer treatment has become a kind of double-edged sword – the number of cancer survivors is rapidly growing, but they are suffering the long-term consequences of the cancer and subsequent treatments. Because of this, the authors call on the medical community to conduct novel research and clinical approaches to limit these late effects of cancer treatment. “Until then,” the authors write, “an optimally integrated follow-up service urgently needs to be developed where the endocrinology should play an essential part.”
“In conclusion,” the authors continue, “late endocrine complications after cancer therapy constitute common health issues in long-term cancer survivors and require life-long surveillance. For many cancer entities focus is shifting from surviving cancer to living beyond cancer, and therefore early diagnosis and treatment of sequelae are essential to ensure a good quality of life and to reduce late morbidity and mortality.”