Recurrence and mortality rates with different treatment approaches of Merkel cell carcinoma: a systematic review and meta‐analysis

Abstract

Background Comprehensive treatment recommendations for Merkel cell carcinoma are complex. We aimed to systematically review the published data on recurrence and mortality rates associated with various treatment approaches for Merkel cell carcinoma.Methods Search of MEDLINE, Embase, Web of Science, and Scopus from inception to August 2015. Studies were included that reported comparative survival and recurrence data for two or more treatment modalities. Two reviewers independently reviewed and abstracted recurrence and mortality rates. Event rates for individual treatment arms in each study were pooled and meta-analyzed across studies using a random-effects model. ResultsFifty-two retrospective studies met inclusion criteria, revealing a total of 1,804 patients with primary Merkel cell carcinoma with data available for analyses. The recurrence rate was higher for surgery alone (55.0%) versus a combination of surgery and radiotherapy (39.0%) (odds ratio, 2.089; 95% CI, 1.374-3.177; P < 0.001). Combination therapy including surgery, radiotherapy, and chemotherapy had a higher mortality rate (44.6%) than did combined surgery and radiotherapy (23.2%) (odds ratio, 2.688; 95% CI, 1.196-6.037; P = 0.02). ConclusionsThe treatment of Merkel cell carcinoma with surgery plus adjuvant radiotherapy may produce lower recurrence rates.

Merkel cell carcinoma of unknown primary: Clinical presentation and outcomes

“…However, this may be due to selection bias given the small sample size and a wide variety of treatment approaches. Although there is also evidence that the effect of traditional chemotherapy on the immune system may in fact lower cause‐specific mortality, in the long run, we did not identify any significant differences in disease recurrence or disease‐specific mortality in patients who received systemic therapy 29,30 . We were unable to directly compare patients receiving traditional chemotherapy with those receiving immunotherapy due to cohort size and crossover between the two groups—of the 11 patients who received immunotherapy, four also received chemotherapy.…”

“…Although there is also evidence that the effect of traditional chemotherapy on the immune system may in fact lower cause-specific mortality, in the long run, we did not identify any significant differences in disease recurrence or diseasespecific mortality in patients who received systemic therapy. 29,30 We were unable to directly compare patients receiving traditional chemotherapy with those receiving immunotherapy due to cohort size and crossover between the two groups-of the 11 patients who received immunotherapy, four also received chemotherapy. Though the size of our adjuvant therapy treatment groups was small and direct statistical comparisons were not sufficiently powered, it does appear that both positive outcomes and negative outcomes were reported in each individual treatment group.…”

Treatment of Locally Advanced Merkel Cell Carcinoma—A Multi-Center Study

“…There are no data to confirm the benefit of perioperative chemotherapy in patients with stage I-III MCC regarding OS [ 5 , 17 , 38 , 40 , 41 ]. A large meta-analysis of 52 trials showed similar recurrence rates for patients receiving chemo-radiotherapy or only radiotherapy in aperioperative setting [ 42 ]. Thus, chemotherapy is not routinely recommended but may be considered in some selected cases, such as marginally resectable lesions.…”

“…Considering high MCC radiosensitivity, patients who are not suitable for surgery or refuse surgery may be offered definitive radiotherapy or radiochemotherapy [ 2 ]. Recent meta-analysis confirmed the noninferiority of this approach [ 42 ]. In our study, five patients treated with curative intent received radiotherapy alone, and only one disease recurrence after treatment was observed.…”

Wide local excision for Merkel cell carcinoma of the lower extremity: A case report

“…However, due to the rare occurrence of this disease, high-quality clinical studies are lacking and treatment recommendations for MCC are complex and varied. Treatment approaches include wide local excision, Mohs surgery, radiotherapy and immunotherapy, as well as different combinations of these treatments (1). For wide local excision, the optimal margin width for primary MCC remains to be fully determined.…”