Merkel cell carcinoma in Taiwan: A series of 24 cases and literature review

Mohs Micrographic Surgery Versus Wide Local Excision in the Treatment of Merkel Cell Carcinoma: A Systematic Review

BACKGROUND

Merkel cell carcinoma (MCC) is an aggressive neoplasm with high rates of recurrences. Current guidelines recommend wide local excision (WLE) with 1 to 2 cm margins. However, Mohs micrographic surgery (MMS) offers a potential advantage over WLE because of its ability of sparing healthy tissue and assessing 100% of margins.

OBJECTIVE

To systematically evaluate the surgical modalities for the treatment of MCC.

MATERIALS AND METHODS

Eligible articles were identified using MEDLINE, Scopus, EMBASE, and Cochrane Library. All available studies investigating surgical treatment of MCC with WLE or MMS were considered.

RESULTS

Forty studies met the inclusion criteria. Thirty-one studies described patients treated with WLE, 3 with MMS, and 6 with either WLE or MMS. Subgroup analysis of Stage I MCC showed recurrence rates similar in both surgical modalities with local recurrence rate of 6.8% for WLE versus 8.5% for MMS (p = .64) and a regional recurrence rate of 15.2% for WLE versus 15.3% for MMS (p = .99).

CONCLUSION

Overall WLE cases were at a higher stage at presentation. Subgroup analysis showed that MMS is not inferior to WLE excision for the treatment of Stage I MCC and is a reasonable option for anatomic locations where tissue sparing is important.

The texture of collagen in the microenvironments of Merkel cell carcinoma

ABSTRACT

Solid tumors typically contain high levels of fibrillar collagen. The increased stromal collagen deposition usually promotes cancer progression since biochemical and biophysical cues from tumor-associated collagen fibers stimulate neoplastic cells. Few studies have investigated the relationship between Merkel cell carcinoma (MCC) and the extracellular matrix (ECM), but there are no works evaluating collagen.This is an observational, analytical, retrospective study including 11 patients with MCC. Primary tumor-stained sections were evaluated by second harmonic generation microscopy and texture analysis.Peritumoral texture features (area fraction, mean gray value, entropy, and contrast) showed much lower values than normal skin (P < .0001) revealing extensively altered structure of peritumoral collagen fibers. These differences were not significant between tumors with unfavorable and favorable known prognostic factors.Profound changes in collagen fibers present in the stroma accompanying primary MCC may contribute to the aggressive behavior of this tumor. Our results indicate that whatever MCC histological subtype, size or anatomical location, MCC promotes the same type of ECM for its development. As an outlook, therapies using ECM macromolecules or fibroblasts (the architects of ECM remodeling) as target could be useful in the treatment of MCC.

A cost-utility analysis of avelumab for metastatic Merkel cell carcinoma in Taiwan

BACKGROUND

Metastatic Merkel cell carcinoma (mMCC) has traditionally been managed with palliative chemotherapy regimens or best supportive care (BSC). Avelumab, a novel anti-programmed death-ligand 1 (PD-L1) human monoclonal antibody for mMCC treatment, is being studied in the pivotal JAVELIN Merkel 200 trial.

AIM

Incorporating trial results, this analysis aimed to evaluate the cost-utility of avelumab in Taiwan.

METHODS AND RESULTS

A de novo partitioned-survival model with three key health states related to survival (progression-free disease, progressed disease, and death) was applied in this study. The data of clinical efficacy, safety, and patient utilities were obtained from the JAVELIN Merkel 200 trial, literature review, and Taiwanese clinical expert opinion. Cost-utility analysis was performed, and results were presented as cost per quality-adjusted life year (QALY) gained. For treatment-naïve patients, the incremental cost-effectiveness ratios (ICERs) for avelumab vs BSC and avelumab vs chemotherapy were US$44885.06 and US$42993.06 per QALY gained, respectively. As to treatment-experienced mMCC patients, avelumab was associated with ICERs of US$27243.06 (vs BSC)/US$26557.43 (vs chemotherapy) per QALY gained. All ICERs remained consistently within the willingness-to-pay (WTP) threshold of US$53,333.33 per QALY gained.

CONCLUSION

This study demonstrated avelumab to be a cost-effective treatment option for both treatment-experienced and treatment-naïve mMCC patients with very poor prognosis in Taiwan.

Primary Merkel Cell Carcinoma: A Retrospective Analysis of 31 Cases in Poland

Introduction

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous neuroendocrine cancer that typically arises in sun-exposed areas of the skin, especially in the elderly. Significant advances have recently been made regarding skin cancers, but data on cases of MCC are rather limited as these patients are frequently grouped together with other non-melanoma skin cancers (NMSC). Here, we performed an analysis of the clinical profile of patients with MCC in Poland to identify major factors influencing the prognosis.

Methods

Approximately 13,000 pathology and medical records were examined to identify patients with MCC diagnosed between 2010 and 2019. The management and outcomes of patients with histologically confirmed MCC were retrospectively evaluated.

Results

Thirty-one patients diagnosed with MCC were identified. The tumor occurred predominantly in women (61.3%) and in the elderly (mean 75.6 years). Twenty-nine patients had locoregional MCC and two had metastatic MCC at the time of diagnosis. Patients in stage I disease had excellent prognosis. In stages II and III, respectively 22.2% and 50.0% of patients developed metastases. Among patients who received chemotherapy with cisplatin and etoposide, 17% achieved partial remission with progression-free survival (PFS) of 8.0 months, and a further 50% achieved stable disease with PFS of 4.0, 4.5, and 4.5 months respectively. In 6 (19.4%) patients MCC coexisted with chronic lymphocytic leukemia (CLL). In all six cases CLL preceded MCC development.

Conclusions

Female gender, tumor-free resection margins, and local disease were found to be independent prognostic factors in MCC progression. Patients with hematological malignancies, immunosuppression, and those with immune deficiencies should be closely followed up as they are predisposed to develop MCC.

Electronic supplementary material

The online version of this article (10.1007/s13555-020-00424-5) contains supplementary material, which is available to authorized users.