Findings from a five-year trial of 5% imiquimod cream for treating superficial and nodular basal cell carcinomas show sustained benefits for those lesions that respond to the cream early, though surgery remains a superior intervention, according to a paper published online ahead of print in Journal of Investigative Dermatology (Dec. 5, 2016).
This research was an extension of an earlier three-year follow-up study comparing 5% imiquimod cream to traditional Mohs excision, which had found an 83.6% success rate for patients treated with imiquimod at three years, versus 98.4% for traditional surgery, according to a press release.
Over the longer five-year period, data was available for 383 participants, with the five-year success rate for imiquimod being 82.5% (170/206), compared with 97.7% (173/177) for surgery (relative risk of imiquimod success = 0.84, 95% confidence interval = 0.77–0.91, p<0.001).
“The absolute response rate for topical imiquimod of 83 per cent at five years, although clearly inferior to the 98 per cent for excisional surgery for low-risk BCC, might still represent a clinically useful treatment modality, because a cream treatment can be carried out in a primary care setting, and some patients may also prefer the option of a cream rather than surgery,” said lead investigator Hywel C. Williams, DSc, FMedSci, NIHR Senior Investigator, Professor of Dermato-Epidemiology and Co-Director of the Centre of Evidence-Based Dermatology at the University of Nottingham, Nottingham, U.K., in the release. “If you had told me 15 years ago that one day we would be treating low risk nodular and superficial BCC with a cream that enhanced the body’s local immune response, I would have walked away. But it is a reality nowadays.”
Most of the treatment failures in the study among those patients who were treated with the imiquimod cream occurred within the first year, which Dr. Williams said supports the idea that should an immune response to the cancer be successfully mounted, that response is sustained, reducing concerns that patients may be vulnerable to ‘submarine’ cancers that may emerge after the visible lesions have been treated.
The investigators write that they hope that these findings will encourage further research to develop creams that work in a similar way, yet produce better results. As well, the findings provide an immediate framework for treating BCC and potentially alleviating some of the burden on specialized health care providers.
“The most important results are the precise estimates of three- and five-year tumour clearance for imiquimod cream versus surgery,” said Dr. Williams. “This will allow patients and their doctors to engage in a shared decision-making conversation on a range of possible treatment options. Because BCC is reaching epidemic proportions, some countries like the U.K. are struggling to keep up. One possible strategy for the future is to treat more low-risk (biopsy proven) BCCs with imiquimod cream and only refer patients who don’t respond to secondary care services.”