My husband is currently undergoing Chemo for Non-Hodgkin's Lympoma, on his 2nd chemo he had his first outbreak before that we didn't even know he have Herpes Simplex. From what I know chemo rack your whole immune system. My husband may have gotten Herpes years ago, stayed dormant, with no symptoms what so ever and because his immune system is so low due to chemo drugs, i believe that is how the virus surfaced.
Herpes infection can also pose a serious problem as well as those undergoing chemo or radiation therapy or taking high does of cortisone preparations. They may suffer the infection in various organs including the eyes, the mucous membranes, the esophagus, the liver, the brain or the lungs. That is what we were told by our doctor.
I don't see how chemotherapy able to treat HSV. Who would want to under go chemo just to cure Herpes and face other possible life threatening side effects from chemo.