A new study has found that testosterone therapies have no link to certain types of cancer. However, concerns about other possible complications remain, as well as related legal actions.

The New Study

A new study was presented at the 2014 Genitourinary Cancers Symposium: “Long-term treatment with testosterone undecanoate injections and its effect of prostate cancer incidence in hypogonadal men.” The new study used data from various cancer registries to study the risk of prostate cancer in men taking androgen-replacement drugs. Androgen replacement drugs are drugs used to compensate for waning testosterone levels found in older males. Androgens are a family of hormones,  which influence muscle mass, energy, libido, and other characteristics. Since hormone changes do have some influence on certain tissues and organs, including the prostate, there was concern that drugs designed to alter androgen/testosterone could increase the risk of developing prostate cancers. However, the study found no link between androgen-replacement therapies and prostate cancer.

Blood Clot Concerns

However, previous studies have found other risks associated with androgen-replacement therapies. Specifically, a November 2013 study, published in the Journal of the American Medical Association(JAMA), found an increased risk of heart attacks and strokes. Specifically, the JAMA study found that patients experienced a 30 percent increase in their risk of heart attack and strokes.

Both heart attacks and stroke are closely related medical problems. In both cases, blood clots form within the bloodstream. These clots then lodge themselves in the blood vessels feeding into critical tissues. This blocks oxygen and nutrients, starving and potentially killing tissues. When such a clot lodges in the blood vessels feeding the brain, it causes a stroke. Similarly, when such a clot lodges in the clots supplying the heart, it can cause certain types of heart attacks.

Legal Action

Lawsuits have been filed by patients who suffered from heart attack and strokes after using androgen-replacement drugs. These lawsuits allege that the manufacturers of androgen-replacement drugs were aware, or reasonably should have been aware, of the serious risks associated with their products. The lawsuits further allege that manufacturers continued to actively promote these drugs, endangering the lives of patients. To support this allegation, some lawsuits cite another 2013 JAMA study that found that a quarter of androgen-replacement patients never even had their testosterone levels tested prior to beginning androgen-replacement drugs.

The litigation against the manufacturers of androgen-replacement drugs has taken the form of individual lawsuits. However, this may lead to group lawsuits like class action lawsuits or multidistrict litigation (MDL). Group lawsuits like class action lawsuits and MDLs allow a group of plaintiffs to seek action against a single defendant for alleged harm. The main difference between class action lawsuits and MDLs is that class action lawsuits start out as group lawsuits while MDLs start as individual lawsuits later coordinated into a single legal action. MDLs are more common in drug lawsuits  than class action lawsuits, since drug lawsuits typically involve unrelated plaintiffs across the country.