Opinion in 2015

Cancer evolution is often depicted using a tree model and many current therapies target gene mutations mapped to the tree trunk. Here, Wei and Hsieh propose a novel paradigm—the river model—and examine how this model might describe phenotypically convergent events to better guide effective cancer control in renal cell carcinoma and overcome treatment-resistance that eventually develops in most patients.

Global interest in testosterone deficiency in men and its treatment with testosterone therapy has increased, but practical aspects of care remain confusing to many practitioners. Here, Aversa and Morgentaler describe the symptoms, signs, and diagnosis of testosterone deficiency and discuss the options for testosterone therapy and treatment monitoring, along with its clinical benefits.

Many patients experience impaired erectile function after prostate cancer treatment and struggle to resume a satisfying sexual relationship. In this Perspectives article, Walker, Robinson and Wassersug provide healthcare professionals with recommendations to facilitate successful sexual recovery and the best outcome for patients and their partners.

Testosterone supplementation therapy for men with hypogonadism remains controversial. The definition of hypogonadism in older men is vague and many of the associated symptoms could be considered to be physiological and not requiring treatment. In this Perspectives, Laurence Klotz considers the evidence—or lack thereof—to support the safety of TST in men with and without prostate cancer, and recommends caution in its use.