A 74 year old man started on bicalutamide for prostate cancer. Approximately 4-6 weeks after starting bicalutamide the patient developed diffuse, tender erythema spreading caudally from facial sites. The distribution is symmetrical and follows a sun exposed pattern with erythema seen across the face, shoulders, upper torso and upper limbs. The medication was stopped following 2 months of treatment. We saw him 4 weeks after the end of therapy in a dermatology outpatient clinic and started him on a tapering dose of Prednisolone, starting at 10mg OD, with daily application of sunscreen and emollients.
A punch biopsy was taken, which demonstrated mild epidermal spongiosis, acanthosis and band-like lymphocytic infiltrates in dermis on haemoxylin and eosin staining. A histologically proven, drug associated lichenoid eruption predominantly at sun exposed sites has been identified. The patient is now awaiting referral to a photoallergy unit for monochromator testing.

Bicalutamide is from the same family of medication as flutamide, a drug which is known to cause photosensitivity reactions. However, few reports of photosensitivity from bicalutamide have been made and the manufacturer lists this reaction as rare.
Following clinical and histological analysis of our case, we believe we have diagnosed photosensitivity secondary to bicalutamide. The incidence of photosensitivity from bicalutamide may be more common than originally thought.

A case of Bicalutimide-inducted photosensitivity reaction