Self-Assessment of Neuropathic Symptoms Following Taxane-Based Chemotherapy for Breast Cancer

Breast cancer (mammary carcinoma) is a malignant disease of the breast tissue characterized by the uncontrolled proliferation of breast cells. Depending on the stage of the disease, treatment may include surgery, radiation therapy, and drug therapies. Many patients also receive chemotherapy before or after surgery, which often includes taxanes such as paclitaxel or docetaxel. These active ingredients stabilize the microtubules—fine tubes in the cell’s cytoskeleton that are necessary for cell division. As a result, rapidly dividing cells—such as cancer cells—can no longer divide properly. The microtubules also transport building blocks and signaling molecules within the long nerve fibers, which is why taxanes can damage the peripheral nerves. As a result, chemotherapy-induced peripheral neuropathy (CIPN) may occur, which usually first manifests in the toes and feet as well as the fingers and hands through tingling, numbness, altered sensation, or pain, and can be very distressing. Exactly how it develops has not yet been conclusively clarified scientifically. No effective prevention is known to date, and treatment options for existing neuropathy are limited, which is why early detection of initial signs is crucial. The aim of this study is to investigate a method that allows patients to self-assess their nerve symptoms. A so-called neuropathy tracker is used to assess the type, severity, and distribution of the symptoms. Patients then test their sensitivity to a pinprick sensation and vibration on both legs, from the toes to the knee. The Neuropathy Tracker guides the patients through this process; the vibration is generated using a cell phone. Finally, the extension strength of both big toes is tested. The data is used to calculate a score, and the study examines the threshold at which mild CIPN can best be distinguished from the absence of neuropathy. There is a single study group, and the study is open-label (not blinded), meaning that both the patients and the study physicians know which procedure is being used. Eligible participants are women aged 18 and older with breast cancer who have previously received taxane-based chemotherapy followed by adjuvant radiation therapy and who have no CIPN or only mild CIPN. Women with skin conditions on their legs, as well as those who are pregnant or breastfeeding, are ineligible to participate.