Patients on anticancer therapeutic agents may develop carpal tunnel syndrome

Carpal tunnel syndrome (CTS) is not uncommon in patients being treated with anticancer therapeutic agents, reports a study. Electrodiagnostic (EDX) studies and ultrasound (US) are necessary in the diagnostic assessment of these individuals.

In this study, the authors described the clinical, EDX, and US findings in seven patients who experienced CTS due to anticancer therapeutic agents. Of these, all underwent EDX testing and four had a US.

CTS developed in four patients on aromatase inhibitors, two on immune checkpoint inhibitors, and one on a selective oestrogen receptor modulator. The mean duration between initiation of the anticancer therapeutic agents and symptom onset was 6 weeks.

All patients experienced decreased digit sensation, while three (42.8 percent) had wasting and weakness of the abductor pollicis brevis (APB). The compound muscle action potentials of the APB and sensory nerve action potentials of the second or third digit could not be recorded in two (28.5 percent) and four (57.1 percent) patients, respectively.

In addition, two patients had fibrillations and positive sharp waves in the APB detected by needle electromyography. In three patients (42.8 percent), there was a decrease in the motor unit potentials of the APB with large polyphasics.

All four patients who underwent US testing showed an increased cross-sectional area of the median nerve at the carpal tunnel inlet, whereas two (75 percent) experienced thenar muscle atrophy, and two (50 percent) had a loss of fascicular pattern. Three patients (42.8 percent) underwent a US-guided carpal tunnel release.

“Physicians should be cognizant of the relationship between anticancer therapeutic agents and CTS,” the authors said.