Imiquimod 5% cream in the treatment of Bowen's disease.
BACKGROUND
Large-diameter lesions of Bowen's disease at sites such as the shin may be difficult to treat surgically and may require alternate treatment modalities.


OBJECTIVE
We investigated whether imiquimod 5% cream, a topical immune response modifier that stimulates the production of interferon alfa and other cytokines, is an effective topical treatment for Bowen's disease.


METHODS
This was a phase II, open-label study in 16 patients, treating a single biopsy-proven plaque of Bowen's disease that was 1 cm or larger in diameter, with once-daily self-application of imiquimod 5% cream for 16 weeks. A biopsy was performed on the treated area 6 weeks after the end of treatment, with patient follow-up at 3 and 6 months. Lymphocyte CD4/CD8 ratios were analyzed in pretreatment and posttreatment biopsy specimens by immunophenotyping the lymphocytic infiltrate.


RESULTS
Sixteen patients with Bowen's disease lesions ranging from 1 to 5.4 cm in diameter (0.7-21.6 cm(2) in area) were treated. Fifteen of these lesions were on the legs, and one was on the shoulder. Fourteen of the 15 patients (93% per protocol analysis) had no residual tumor present in their 6-week posttreatment biopsy specimens. One patient died of unrelated intercurrent illness before a biopsy specimen could be obtained. The median CD4/CD8 lymphocyte ratio in pretreatment biopsy specimens was 2:1, and this was reversed to a median of 1:2.2 in the posttreatment specimens. Ten patients completed 16 weeks of treatment, but 6 patients ceased treatment early (between 4 and 8 weeks) because of local skin reactions.


CONCLUSIONS
Imiquimod 5% cream appears to be an effective treatment for Bowen's disease on the lower limbs. The 93% positive treatment response in biopsy-proven cases (excludes patient who died from an intercurrent illness who did not undergo a posttreatment biopsy) compares favorably with other current treatment modalities. The dosing schedule and length of treatment for Bowen's disease require further evaluation.
Mackenzie-Wood
A
A
Skin and Cancer Foundation, Darlinghurst, NSW, Australia.
Kossard
S
S
de Launey
J
J
Wilkinson
B
B
Owens
M L
ML
D000287:Administration, Topical; D000368:Aged; D000634:Aminoquinolines / Q000008:administration & dosage / Q000627:therapeutic use*; D001706:Biopsy; D001913:Bowen's Disease / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D006801:Humans; D000077271:Imiquimod; D007369:Interferon Inducers / Q000008:administration & dosage / Q000627:therapeutic use*; D007866:Leg / Q000473:pathology; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
D000634:Aminoquinolines; D007369:Interferon Inducers; D000077271:Imiquimod