Treating BCC: Imiquimod therapy sustains clearance for five years

November 1, 2008

Several therapies are available for the treatment of superficial basal cell carcinoma (BCC), including excision, PDT, 5-fluorouracil and imiquimod; however, not all of them have the same safety and efficacy profile. A recent study proves that imiquimod is safe and effective for the treatment of superficial BCC and assures sustained clearance over at least five years.

Key Points

Harald P.M. Gollnick, M.D., professor, University Clinic of Dermatology and Venereology, Otto-von-Guericke University, Magdeburg, Germany, headed a phase 3, multicenter, open-label European study that evaluated the clearance rates of superficial BCCs following treatment with 5 percent imiquimod cream at a 12-week post-treatment visit and assessed whether patients remained clear of tumor at the treated site during five years of long-term follow-up.

Study parameters

Patients applied 5 percent imiquimod cream once daily, five times a week for six weeks.

The clinical clearance of the lesions were assessed at 12 weeks (for initial clearance); at three, six, and 12 months; and two, three, four and five years after the initial 12-week visit (for sustained clearance).

Sustained clearance rate was achieved if patients who initially cleared remained clinically clear of superficial BCC at the target tumor site throughout the five-year follow-up period.

Results

Results showed that 90 percent (163 of 182 patients) achieved initial clinical clearance. The estimated sustained clearance rates were 98, 95, 94, 91, 91, 90 and 87 percent at months three and six, and year one, two, three, four and five, respectively.

Thus, if recurrences occurred, they mostly occurred during the first nine months after the end of treatment.

Recurrence

"We found that in terms of clinical tumor recurrence, the long-term effectiveness of imiquimod was, with nearly 87 percent - and, considering histology, with more than 90 percent - very good.

"Most of the recurrences occurred within the first nine months after end of treatment. Follow-up is particularly important during this period. After that time point, however, the excellent therapeutic and cosmetic effect seemed to be sustained.

"Obviously, the tumor at the treated site appeared to be eradicated, underscoring the therapeutic value of imiquimod," Dr. Gollnick tells Dermatology Times.

Adverse events

Dr. Gollnick says no serious adverse events were linked with the imiquimod treatment in the study patients, and the common adverse events that occurred in the study were not any different than the expected local skin reactions (LSRs) seen in other similar trials with the immune modulator or other therapeutic approaches.

LSRs included erythema, erosion, scabbing and crusting, ulceration, edema and induration, scaling and flaking, and vesicle formation at the treated lesion site.

Most of the LSRs resolved within three months of follow-up, and only a few patients experienced a mild persistent erythema that took up to two years to resolve.

Skin quality assessments

Dr. Gollnick reported that, compared to baseline, most patients improved in their skin quality assessments (SQA), which included hypo-and hyperpigmentation, scarring, atrophy, skin surface (rough/dry/scaly) and pigmentation (mottled/irregular), and that these signs remained generally stable after year one of treatment.

Hypopigmentation was the only SQA that increased in 40 percent of study participants.

Treatment options

"There are several treatments that can be used for the treatment of superficial BCC today, including excision, PDT and Efudex (5-fluorouracil, Valeant) cream. We found that the effectiveness of imiquimod is no less impressive for the treatment of superficial BCC than other leading therapies.

"However, this study proves that superficial BCCs can be safely and effectively treated with an excellent long-term outcome and without any worry of serious adverse events, as sometimes seen with other therapies such as 5-FU cream.

"Immunobiological options like imiquimod should be considered, in particular, when cosmetic outcome is an important factor," Dr. Gollnick says.

Disclosure: The study was sponsored by 3M Pharmaceuticals and MEDA Pharma.