This article is more than 5 years old. Information may no longer be current.

Radiotherapy found to be efficacious option for Merkel cell carcinoma

Definitive radiotherapy for macroscopic locoregional Merkel cell carcinoma had local and regional in-field control and should be considered an efficacious and potential curative option, according to study results published in the Journal of the American Academy of Dermatology.

“Consensus management of locoregional [Merkel cell carcinoma (MCC)] is yet to be reached because of the rarity of the diagnosis and lack of randomized data,” Dakshika A. Gunaratne, BMed, MS, MPH, of the department of otolaryngology, head and neck surgery, Westmead Hospital, Sydney, and colleagues, wrote. “Current recommendations from the National Comprehensive Cancer Network advocate first-line wide local excision of the primary tumor … Radiation monotherapy is suggested for select cases if complete surgical excision is unattainable.”

MCC is often reported in elderly white men, who may be sicker and not ideal candidates for surgery, the researchers noted.

They conducted a literature search of Medline, PubMed and Embase databases to identify cases of definitive radiotherapy for locoregional MCC. The analysis included 23 studies with 246 patients.

Among the 332 MMC sites that underwent irradiation, 51.5% were primary sites, 48.2% were regional and 0.3% were in-transit. There was no difference in mean radiation dose between primary sites (48.7 Gy) and regional sites (49.4 Gy).

The rate of recurrence based on disease site was 11.7% and the rate per patient was 14.3%.

There was a higher likelihood of recurrence at a regional irradiated site (16.3%) than a primary irradiated site (7.6%; OR = 2.4; 95% CI, 1.66-4.77). Radiotherapy dose and incidence of recurrence or nonrecurrence were not associated in primary irradiated sites (42.7 Gy vs. 49.3 Gy) or regional irradiate sites (48.6 Gy vs. 49.5 Gy).

“There are very few contraindications to recommending radiotherapy, if indicated, even in poor-performance patients,” the researchers concluded. “On the basis of the available evidence, clinicians should consider radiotherapy as an efficacious and potentially curable option in patients, especially those of poor performance status and when risks of surgery are deemed unacceptable or the patient refuses surgery.” – by Bruce Thiel

Disclosure: The researchers report no relevant financial disclosures.