Herpes infections in breast cancer patients treated with adjuvant chemotherapy

There is little information on Herpes zoster infection in breast cancer patients as a complication during adjuvant chemotherapy. The aim of this study is to evaluate the incidence of Herpes zoster and simplex infections in this patients setting.

We analyzed 623 early-stage breast cancer patients in our Institute over a period of 7 years (1998-2005). Four-hundred and sixty-one patients were treated with anthracycline-based chemotherapy, 116 with CMF and 46 with taxane-containing regimens.

Twelve (1.9%) developed herpes zoster; 9 patients, receiving anthracycline-based chemotherapy, two taxane-containing regimens, and one CMF regimen. Herpes zoster infection required treatment delay in 6 patients. Adjuvant chemotherapy was delayed for 1 week in 2 patients, while in 4 patients with more severe symptoms chemotherapy was delayed for 2 weeks. One patient, despite i.v. acyclovir, had severe postherpetic motor neuropathy with a permanent ambulation impairment, and chemotherapy was stopped. In our study, herpes zoster occurred in 55/1,000 cases/year. The reported incidence in the general population varies between 2.2 and 4.1 per 1,000 patients/year; therefore, the risk of developing herpes zoster in these patients may be 13- to 25-fold higher compared to the incidence in the general population. In addition, 13 of 623 patients developed herpes simplex.

Our findings suggest that adjuvant chemotherapy can facilitate reactivation of herpes infection.