Chemotherapy of metastatic Merkel cell carcinoma: case report and review of the literature

The Role of Radiation, Immunotherapy, and Chemotherapy in the Management of Locally Advanced or Metastatic Cutaneous Malignancies

INTRODUCTION

Skin cancer impacts a significant proportion of the population. While surgical management is often the mainstay of treatment, advanced or metastatic cutaneous malignancies require additional local and/or systemic therapies.

METHODS

A review of the literature was performed studying the use of radiation therapy, chemotherapy, and immunotherapy for locally advanced or metastatic cutaneous malignancies.

RESULTS

A summary of the present literature on the management of locally advanced or metastatic cutaneous malignancies is presented across cutaneous head and neck basal cell carcinoma, squamous cell carcinoma, melanoma, and Merkel cell carcinoma. The addition of multidisciplinary therapies to resection is often associated with improved outcomes.

CONCLUSION

The management of cutaneous head and neck malignancies requires an approach integrating multiple specialties, to optimize outcomes and minimize toxicities.

The Evaluation and Treatment of Merkel Cell Carcinoma and Brain Metastasis: A Case Report and Review of the Literature

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine tumor associated with high mortality if metastases are identified. Currently, there is no standardized nor curative treatment for neurometastatic MCC. In this study, we have reviewed the more recent cases and the use of immunotherapy in a population. In this case report and review, we present a case of MCC with brain metastasis currently undergoing treatment with immunotherapy (pembrolizumab) resulting in an initial complete response with a progression-free survival time of five months. We also review the past reported literature and the 11 newly presented cases on their clinical presentation of neurometastatic MCC, immunohistochemical markers, and treatment outcomes. In summary, immunotherapy initially showed a promising response with the complete elimination of MCC brain metastasis. The early aggressive treatment of pembrolizumab with stereotactic radiosurgery should be considered as this treatment plan has shown improved therapeutic effects compared to the standard chemoradiation therapy. Further investigations are needed to determine the efficacy and response of immunotherapy use for neurometastatic MCC.

Folate hydrolase-1 (FOLH1) is a novel target for antibody-based brachytherapy in Merkel cell carcinoma

Backgrounds

Folate Hydrolase‐1 (FOLH1; PSMA) is a type II transmembrane protein, luminally expressed by solid tumour neo‐vasculature. Monoclonal antibody (mAb), J591, is a vehicle for mAb‐based brachytherapy in FOLH1+ cancers. Brachytherapy is a form of radiotherapy that involves placing a radioactive material a short distance from the target tissue (e.g., on the skin or internally); brachytherapy is commonly accomplished with the use of catheters, needles, metal seeds and antibody or small peptide conjugates. Herein, FOLH1 expression in primary (p) and metastatic (m) Merkel cell carcinoma (MCC) is characterized to determine its targeting potential for J591‐brachytherapy.

Materials & Methods

Paraffin sections from pMCC and mMCC were evaluated by immunohistochemistry for FOLH1. Monte Carlo simulation was performed using the physical properties of conjugated radioisotope lutetium‐177. Kaplan–Meier survival curves were calculated based on patient outcome data and FOLH1 expression.

Results

Eighty‐one MCC tumours were evaluated. 67% (54/81) of all cases, 77% (24/31) pMCC and 60% (30/50) mMCC tumours were FOLH1+. Monte Carlo simulation showed highly localized ionizing tracks of electrons emitted from the targeted neo‐vessel. 42% (34/81) of patients with FOLH1+/− MCC had available survival data for analysis. No significant differences in our limited data set were detected based on FOLH1 status (p = 0.4718; p = 0.6470), staining intensity score (p = 0.6966; p = 0.9841) or by grouping staining intensity scores (− and + vs. ++, +++, +++) (p = 0.8022; p = 0.8496) for MCC‐specific survival or recurrence free survival, respectively.

Conclusions

We report the first evidence of prevalent FOLH1 expression within MCC‐associated neo‐vessels, in 60‐77% of patients in a large MCC cohort. Given this data, and the need for alternatives to immune therapies it is appropriate to explore the safety and efficacy of FOLH1‐targeted brachytherapy for MCC.

What's already known about this topic?

We report the first evidence of prevalent folate hydrolase‐1 (FOLH1; also known as prostate‐specific membrane antigen) expression within MCC‐associated neovessels.

What does this study add?

Herein, FOLH1 expression in Merkel cell carcinoma neovasculature is validated, and the therapeutic mechanism of specific, systemic targeting of disseminated disease with antibody‐based brachytherapy, is defined.

An analysis of the use of targeted therapies in patients with advanced Merkel cell carcinoma and an evaluation of genomic correlates of response

Background

The use of targeted therapy remains a treatment consideration for some patients with advanced Merkel cell carcinoma (MCC). However, supportive data on the use of targeted therapy approaches are limited. Thus, we sought to evaluate the responsiveness of targeted agents in patients with advanced MCC.

Methods

An institutional MCC database identified patients who were treated with targeted therapy. For the purpose of this study, targeted therapy was defined as any multi‐targeted tyrosine kinase inhibitor or inhibitor of the PI3K‐pathway. Clinical benefit was defined as complete response, partial response, or stable disease (SD) ≥6 months. A subset of patient samples underwent next‐generation sequencing (NGS), Merkel cell polyomavirus testing, and PD‐L1/PD‐1 expression testing.

Results

Nineteen patients with MCC treated with targeted therapy were identified, 21 targeted therapy regimens were evaluable for response in 18 patients. Four of twenty‐one (19%) of evaluable regimens were associated with clinical benefit with the best overall response of SD. The durations of SD were 13.6 months (59 weeks), 9.7 months (42 weeks), 7.6 months (33 weeks), and 7.2 months (31 weeks). Of the four patients who derived clinical benefit, three were treated with pazopanib alone and one was treated with pazopanib plus everolimus. No difference in the rate of clinical benefit between molecular disease subtypes was detected nor was associated with any specific genomic alteration.

Conclusion

In our series, targeted agents elicited a disease control rate of 19% in patients with advanced MCC, with a best overall response of SD. Pazopanib alone or in combination exhibited a rate of disease control of 36% (4 of 11 with SD ≥6 months).

Cerebral metastasis of Merkel cell carcinoma following resection with negative margins and adjuvant external beam radiation: a case report

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine tumor of the skin. It is associated with advanced age, ultraviolet (UV) radiation, and Merkel cell polyomavirus. It has a predilection for the lymphatic system, but rarely spreads to the central nervous system.

CASE PRESENTATION

A 71-year-old Caucasian man with a history of rheumatoid arthritis and MCC of the right lower eyelid and cheek presented with left-sided hemineglect and word-finding difficulty. Twenty months earlier he had undergone local excision of a 3 cm lesion with negative margins, negative sentinel lymph node biopsy, and external beam radiation. On presentation he was found to have a 6.3 cm mass in the right frontotemporal region. He underwent prompt resection, with pathological analysis consistent with metastatic MCC. He subsequently underwent stereotactic radiosurgery (SRS) and adjunctive immunotherapy with pembrolizumab. He has since tolerated the therapy well and is currently without neurological symptoms or evidence of recurrence.

CONCLUSIONS

Cerebral metastasis of MCC is a rare event and should be considered when a patient with a history of MCC presents with neurological symptoms. Optimal treatment regimens of these rare cases are unclear; however, prompt resection, stereotactic radiosurgery, and adjunctive immunotherapy have shown an initial positive response in this patient.

The Genomic Landscape of Merkel Cell Carcinoma and Clinicogenomic Biomarkers of Response to Immune Checkpoint Inhibitor Therapy

PURPOSE

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy, which has demonstrated sensitivity to immune checkpoint inhibitor therapy. Here, we perform the largest genomics study in MCC to date to characterize the molecular landscape and evaluate for clinical and molecular correlates to immune checkpoint inhibitor response.

EXPERIMENTAL DESIGN

Comprehensive molecular profiling was performed on 317 tumors from patients with MCC, including the evaluation of oncogenic mutations, tumor mutational burden (TMB), mutational signatures, and the Merkel cell polyomavirus (MCPyV). For a subset of 57 patients, a retrospective analysis was conducted to evaluate for clinical and molecular correlates to immune checkpoint inhibitor response and disease survival.

RESULTS

Genomic analyses revealed a bimodal distribution in TMB, with 2 molecularly distinct subgroups. Ninety-four percent (n = 110) of TMB-high specimens exhibited an ultraviolet light (UV) mutational signature. MCPyV genomic DNA sequences were not identified in any TMB-high cases (0/117), but were in 63% (110/175) of TMB-low cases. For 36 evaluable patients treated with checkpoint inhibitors, the overall response rate was 44% and response correlated with survival at time of review (100% vs. 20%, P < 0.001). Response rate was 50% in TMB-high/UV-driven and 41% in TMB-low/MCPyV-positive tumors (P = 0.63). Response rate was significantly correlated with line of therapy: 75% in first-line, 39% in second-line, and 18% in third-line or beyond (P = 0.0066). PD-1, but not PD-L1, expression was associated with immunotherapy response (77% vs. 21%, P = 0.00598, for PD-1 positive and negative, respectively).

CONCLUSIONS

We provide a comprehensive genomic landscape of MCC and demonstrate clinicogenomic associates of immunotherapy response.

Budget impact model of avelumab in patients with metastatic merkel cell carcinoma in the US

Objective: To estimate the budget impact of avelumab as a treatment option for patients with treatment-naïve first-line (1L) and previously treated second-line or later (2L+) metastatic Merkel cell carcinoma (mMCC) in the US.

Methods: A budget impact model was developed to evaluate the addition of avelumab for the treatment of mMCC patients using a hypothetical 30 million-member US health plan over a 3-year time horizon (2019–2021). The comparator treatments included in the analysis were pembrolizumab and nivolumab (other immuno-oncology agents); and the chemotherapies routinely used in the eligible mMCC population. Model inputs included market share uptake of avelumab and other comparators, duration of treatments, and costs (drugs, health care resource utilization, adverse events). The model was evaluated from a commercial payer perspective. Sensitivity analyses were conducted to test uncertainties arising from the input values used in the model.

Results: In a hypothetical commercial health plan of 30 million members, 285 patients with mMCC were identified over 3 years; 43 patients received avelumab as a 1L treatment over 3 years. In a world without avelumab, the total health care costs of treating patients with mMCC over 3 years were estimated to be US$11,710,115 from a commercial health plan perspective. With avelumab, there were estimated savings of $2,643,173 considering the total costs related to the treatment of mMCC over 3 years (23% reduction in the budget). The incremental cost per member per month over 3 years was −$0.0025.

Conclusion: The model results indicate that the adoption of avelumab as a treatment option for mMCC would likely result in minimal budget impact from a US health plan perspective. Patients with mMCC, a rare condition with a poor prognosis and high unmet need, may benefit greatly from recently approved immunotherapies.

Merkel cell carcinoma of the thigh: case report and review of the literature

BACKGROUND

Merkel cell carcinoma (MCC) is a kind of cutaneous neuroendocrine cancer with a poor prognosis. It is characterized by a high rate of recurrence and metastases, including distant metastases and regional nodal metastases. Clinically, MCC often manifests as obvious single painless hard nodules visible in sun irradiation of diameter <2 cm and not uncommonly >2 cm, with rapid growth and metastases, especially lymph node metastases. Due to the aspecific nature of MCC, it is often confused with other skin cancers. Exploring different treatments of MCC is necessary.

CASE PRESENTATION

The current study describes the case of an 86-year-old retired man, who presented with a 2.5×2.0×1.2 cm red nodule on the right thigh, which was initially diagnosed as subcutaneous small cell cancer. Upon histological and immunohistochemical analysis, the tumor was consistent with a diagnosis of MCC.

RESULTS

Antiangiogenic therapy combining endostar and apatinib was administered and a partial response achieved after 2.0 months of treatment, and 6.5 months of progression-free survival was achieved. Overall survival was 13.0 months.

CONCLUSION

We believe that antiangiogenic therapy is an extremely effective treatment for MCC, especially for patients who cannot tolerate chemotherapy and radiotherapy.

Medical Treatment of Neuroendocrine Tumors

Background

Tumors of the neuroendocrine system are characterized by amine precursor uptake and decarboxylation, and they represent a heterogeneous group of carcinomas including carcinoids, islet cell carcinomas of the pancreas, medullary thyroid carcinomas and Merkel cell carcinomas. Their similar cytochemical and ultrastructural properties sustain the hypothesis of a common embryologic origin within the neural crest. Many of these tumors grow slowly, and reducing tumor burden represents the treatment of choice. However, when surgery is not feasible, medical treatment has to be considered. Therapeutic approaches in metastatic disease often do not consider the different biologic behaviors of these neoplasms. Moreover, efficacy of the treatment is associated with lack of a clear definition of the type of response: objective, symptomatic or biochemical.

Methods

In this review we have analyzed the different medical approaches used in the treatment of neuroendocrine tumors in an attempt to define their precise role in the different neoplasms.

Results

In carcinoid tumors, immunotherapy and the somatostatin analogue can be efficaciously used for the control of carcinoid syndrome. For inhibition of tumor growth, chemotherapy should be used only in patients with rapidly progressive disease, and the results are still unsatisfactory.

Conclusions

Although all these tumors appear to have similar cytochemical properties, the responsiveness of the various neoplasms is very different. In the future, a specific treatment modality and a clear definition of the type of response (objective, symptomatic or biochemical) need to be defined for each type of neuroendocrine tumor.

Clinical Experience on Eight Cases of Merkel Cell Carcinoma

Merkel cell carcinoma is a rare neuroendocrine neoplasm of the skin. The tumor most frequently affects elderly patients, with a preference for the head and neck. Eight patients affected by Merkel cell carcinoma have been observed at the General Surgery Unit II of the “Istituti Ospitalieri” hospital in Cremona, each in different stages of the disease; 75% of the cases involved the extremities, and in nearly all of the cases the tumor was nodular in appearance, with an average diameter of 2.2 cm. In 2 cases, the tumor was associated with rheumatoid arthritis, suggesting a dependency on the part of the neoplasm on the immune disorder and on steroid treatment. The available data confirm that in stage I of the disease, surgical treatment should be associated with radiotherapy in order to control the development of local relapses or metastases over time. In this stage, we observed a survival of 34 months (range, 24-48). In stages II and III, survival time falls, with very short duration of responses and poor quality of life as a result of the administration of cytotoxic molecules. Bearing in mind that any local relapse tends to appear within 12 months of the removal of the primitive tumor, that lymph node metastases appear in almost half of the patients, and that metastases over time are manifested in over a third of patients, it is essential to adopt a treatment capable of balancing the demand for longer remissions with a better quality of life. In this situation, we observed that treatment with somatostatin analogues achieves interesting responses without side effects, which suggests a close biological relationship between the tumor and somatostatin and that making a careful assessment of the prognostic factors of the disease can guarantee a correct therapeutic choice.

Nonprogression with avelumab treatment associated with gains in quality of life in metastatic Merkel cell carcinoma

AIM

To assess the association between tumor response and health-related quality of life (HRQoL) in patients with metastatic Merkel cell carcinoma treated with the anti-PD-L1 avelumab.

MATERIALS & METHODS

Phase II single-arm trial (NCT02155647) data of 88 patients were analyzed. Correlations between percentage reduction in tumor size and change from baseline in Functional Assessment of Cancer Therapy - General (FACT-G), FACT - Melanoma (FACT-M) and EuroQol-5 Dimension scores were calculated. HRQoL and utility by tumor response (per the Response Evaluation Criteria In Solid Tumors version 1.1) was estimated.

RESULTS

Tumor shrinkage correlated positively with patients' change from baseline in the FACT-M total (0.364 [95% CI: 0.050-0.607]) and subscale scores. Differences in HRQoL and utility between nonprogressive disease and progressive disease were clinically relevant.

CONCLUSION

In patients with metastatic Merkel cell carcinoma, nonprogression during treatment with avelumab correlated with gains in HRQoL.

Merkel Cell Carcinoma with Distant Metastasis to the Clivus Causing Symptoms Mimicking Tolosa-Hunt Syndrome: A Case Report and Literature Review

Merkel cell carcinoma (MCC) is an uncommon but highly malignant neuroendocrine tumor of the skin. MCC can metastasize, but involvement of the central nervous system is rare. Here, we report a case of rapidly progressing metastatic MCC to the clivus and bilateral cavernous sinus in an immunocompromised patient. This case is unique in that it is the first case report showing MCC metastasis to the clivus from a distant site. It also demonstrates that a MCC metastasis can masquerade with symptoms of Tolosa–Hunt syndrome. A literature review on MCC with CNS metastasis is presented.

Evaluation of real-world treatment outcomes in patients with distant metastatic Merkel cell carcinoma following second-line chemotherapy in Europe

Background and aims

Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer; few treatments exist for patients with advanced disease. Once tumors metastasize to distant sites, patients generally receive chemotherapy, but response duration and progression-free survival (PFS) are typically short. Few studies have assessed the efficacy of second-line chemotherapy for metastatic MCC. Here, we studied outcomes in patients who received ≥ 2 lines of chemotherapy for metastatic MCC.

Materials and methods

Patients in an MCC-specific registry diagnosed with stage IV MCC between November 1, 2004, and September 15, 2015, and treated with second-line or later chemotherapy were analyzed retrospectively. Patient records, including baseline characteristics, immunocompetent status, and responses to prior chemotherapy, were evaluated. Patients meeting eligibility criteria were followed through December 31, 2015.

Results

Of 29 patients with metastatic MCC and immunocompetent status who had received ≥ 2 lines of chemotherapy, 3 achieved a partial response, for an objective response rate (ORR) of 10.3% (95% CI, 2.2–27.4). In the overall population including patients with immunocompetent and immunocompromised status (n = 34), the ORR was 8.8% (95% CI, 1.9–23.7). The median duration of response was 1.9 months (range, 1.3–2.1 months; 95% CI, 1.3–2.1). In the immunocompetent population, median PFS and overall survival were 3.0 months (95% CI, 2.5–6.0) and 5.3 months (95% CI, 4.3–6.0), respectively.

Conclusions

The low response rates and limited durability confirm previous reports of the ineffectiveness of second-line or later chemotherapy in patients with metastatic MCC and provide a benchmark for assessing clinical benefit of new treatments.

Systematic literature review of efficacy, safety and tolerability outcomes of chemotherapy regimens in patients with metastatic Merkel cell carcinoma

AIM

Merkel cell carcinoma (MCC) is a rare neuroendocrine, cutaneous malignancy with poor prognosis once metastasized. The aim of this study was to conduct a systematic literature review to assess clinical outcomes associated with chemotherapy regimens in metastatic MCC.

MATERIALS & METHODS

Embase^®, MEDLINE^®, MEDLINE^®-In-Process and CENTRAL were searched for studies published in January 2016.

RESULTS & CONCLUSION

Overall, the literature on chemotherapy in patients with metastatic MCC is sparse, with most studies being case series/reports. Across all studies, response rates ranged from 20 to 61%, with higher response rates in first-line setting (53-61%) versus second-line setting (23-45%). Among responders, duration of response was short (≤8 months) in both first- and second-line settings. There is a need for novel agents that can induce durable responses in metastatic MCC.

Merkel cell carcinoma: Epidemiology, prognosis, therapy and unmet medical needs

Merkel cell carcinoma (MCC) is a rare skin cancer that is associated with Merkel cell polyomavirus infection in most cases. Incidence rates of MCC have increased in past decades. Risk factors for MCC include ultraviolet light exposure, immunosuppression and advanced age. MCC is an aggressive malignancy with frequent recurrences and a high mortality rate, although patient outcomes are generally more favourable if the patient is referred for treatment at an early stage. Although advances have been made recently in the MCC field, large gaps remain with regard to definitive biomarkers and prognostic indicators. Although MCC is chemosensitive, responses in advanced stages are mostly of short duration, and the associated clinical benefit on overall survival is unclear. Recent nonrandomised phase 2 clinical trials with anti-PD-L1/PD-1 antibodies have demonstrated safety and efficacy; however, there are still no approved treatments for patients with metastatic MCC. Patients with advanced disease are encouraged to participate in clinical trials for treatment, indicating the largely unmet need for durable, safe treatment within this population.

Cerebral metastases from Merkel cell carcinoma: long-term survival

Merkel cell carcinoma is a rare primary cutaneous neuroendocrine tumour that is locally aggressive. In most cases the primary treatment is local surgical excision; however, there is a high incidence recurrence both local and distant. Cerebral metastases from Merkel cell carcinoma are extremely uncommon with only 12 cases published in the literature. This case is particularly unusual in that, not only was no established primary lesion identified, but also the patient has survived for 10 years following initial diagnosis and for 9 years following excision of a single brain metastasis.

Avelumab in patients with chemotherapy-refractory metastatic Merkel cell carcinoma: a multicentre, single-group, open-label, phase 2 trial

BACKGROUND

Merkel cell carcinoma is a rare, aggressive skin cancer with poor prognosis in patients with advanced disease. Current standard care uses various cytotoxic chemotherapy regimens, but responses are seldom durable. Tumour oncogenesis is linked to Merkel cell polyomavirus integration and ultraviolet-radiation-induced mutations, providing rationale for treatment with immunotherapy antibodies that target the PD-L1/PD-1 pathway. We assessed treatment with avelumab, an anti-PD-L1 monoclonal antibody, in patients with stage IV Merkel cell carcinoma that had progressed after cytotoxic chemotherapy.

METHODS

In this multicentre, international, prospective, single-group, open-label, phase 2 trial, patients with stage IV chemotherapy-refractory, histologically confirmed Merkel cell carcinoma (aged ≥18 years) were enrolled from 35 cancer treatment centres and academic hospitals in North America, Europe, Australia, and Asia. Key eligibility criteria were an ECOG performance status of 0 or 1, measurable disease by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, adequate haematological, hepatic, and renal function, and immune-competent status (patients with HIV, immunosuppression, haematological malignancies, and previous organ transplantation were excluded). Patient selection was not based on PD-L1 expression or Merkel cell polyomavirus status. Collection of biopsy material or use of archival tissue for these assessments was mandatory. Avelumab was given intravenously at a dose of 10 mg/kg every 2 weeks. The primary endpoint was confirmed objective response (complete response or partial response) assessed according to RECIST version 1.1 by an independent review committee. Safety and clinical activity were assessed in all patients who received at least one dose of study drug (the modified intention-to-treat population). This trial is registered with ClinicalTrials.gov as NCT02155647.

FINDINGS

Between July 25, 2014, and Sept 3, 2015, 88 patients were enrolled and received at least one dose of avelumab. Patients were followed up for a median of 10·4 months (IQR 8·6-13·1). The proportion of patients who achieved an objective response was 28 (31·8% [95·9% CI 21·9-43·1]) of 88 patients, including eight complete responses and 20 partial responses. Responses were ongoing in 23 (82%) of 28 patients at the time of analysis. Five grade 3 treatment-related adverse events occurred in four (5%) patients: lymphopenia in two patients, blood creatine phosphokinase increase in one patient, aminotransferase increase in one patient, and blood cholesterol increase in one patient; there were no treatment-related grade 4 adverse events or treatment-related deaths. Serious treatment-related adverse events were reported in five patients (6%): enterocolitis, infusion-related reaction, aminotransferases increased, chondrocalcinosis, synovitis, and interstitial nephritis (n=1 each).

INTERPRETATION

Avelumab was associated with durable responses, most of which are still ongoing, and was well tolerated; hence, avelumab represents a new therapeutic option for advanced Merkel cell carcinoma.

FUNDING

Merck KGaA, Darmstadt, Germany.

Merkel Cell Carcinoma: Current Issues Regarding Diagnosis, Management, and Emerging Treatment Strategies

Merkel cell carcinoma (MCC) is a rare but aggressive cutaneous tumor with a predilection for the head and neck of elderly Caucasian patients. Although much less common than melanoma, MCC has higher rates of sentinel lymph node involvement, local and regional recurrences, and mortality. The majority of MCC cases have been linked to the relatively newly discovered Merkel cell polyomavirus, which is a ubiquitous constituent of the skin flora. Recent discoveries regarding viral integration and carcinogenesis and the immunologic features of MCC have expanded the understanding of MCC. These discoveries have led to the development and application of emerging therapies such as somatostatin analogs, immune checkpoint inhibition, adoptive cell therapy, and other exciting possibilities for targeted therapy.

Effect of the dual phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor NVP-BEZ235 against human Merkel cell carcinoma MKL-1 cells

Merkel cell carcinoma (MCC) is an aggressive skin cancer with an increasing incidence. Aberrant activation of the phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway is common in human cancers and has been revealed to play an important function in cell proliferation, metabolism and tumorigenesis. In the present study, NVP-BEZ235, a dual PI3K/mTOR inhibitor, was revealed to be effective in inhibiting proliferation and inducing cell cycle arrest in MKL-1 cells. Additional investigations revealed that NVP-BEZ235 attenuated PI3K/Akt/mTOR signaling and upregulated the levels of the cell cycle inhibitors p21 and p27. Overall, the present results possess considerable implications for future development of dual PI3K/mTOR inhibitor as potential agents in the management of MCC.

Merkel cell carcinoma: a retrospective study on 48 cases and review of literature

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine tumor of the skin. Fourty-eight patients with MCC were observed at the Rare Hormonal Tumors Group of Cremona Hospital, 15 of these with unknown primary site. Due to rarity of Merkel cell carcinoma, clinical experience is generally limited. Data from our series confirm the current recommendations. Wide surgical excision must be associated with radiotherapy also in early stages in order to avoid local relapse and the rapid progression of disease. In advanced stages chemotherapy is the standard despite the short duration of responses and poor quality of life. The data of our series, characterized by a high demand for second opinion, offer some insight about the real rarity of the tumor, the difficulty of managing of disease in our country secondary to a wrong cultural approach to the problem, the indiscriminate use of molecules unnecessary and often expensive, the lack of protocols, and the presence of guidelines often ignored. This results in very poor survival associated with a very low quality of life, requiring to find the right direction towards a correct management of disease.

Intracranial spread of Merkel cell carcinoma to the cerebellopontine angle

BACKGROUND

Merkel cell carcinoma (MCC) is a rare, highly malignant, and aggressive dermal neuroendocrine neoplasm that rarely metastasizes to the central nervous system.

OBJECTIVE

To review the current literature regarding treatment of neurometastatic MCC.

METHODS

A case of a 78-year-old male with intracranial extra-axial metastatic MCC involving the left cerebellopontine angle is presented.

RESULTS

A retrosigmoid craniectomy was performed with complete resection of the metastatic focus. Adjuvant treatment included whole-brain radiation therapy followed by etoposide and carboplatin chemotherapy. Seven months postoperatively, the patient was free of metastatic disease.

CONCLUSION

Surgical resection should be performed when feasible to prevent local recurrence. This may be followed by early adjuvant fractionated whole-brain radiotherapy and systemic chemotherapy; however, no clinical trials have been performed to demonstrate a survival benefit.

Clinical emergence of neurometastatic merkel cell carcinoma: a surgical case series and literature review

Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine neoplasm of possible viral origin and is known for its aggressive behavior. The incidence of MCC has increased in the last 15 years. Merkel cell carcinoma has the potential to metastasize, but rarely involves the central nervous system. Herein, we report three consecutive surgical cases of MCC presenting at a single institution within 1 year. We used intracavitary BCNU wafers (Gliadel^®) in two cases. Pathological features, including CK20 positivity, consistent with MCC, were present in all cases. We found 33 published cases of MCC with CNS involvement. We suggest that the incidence of neurometastatic MCC may be increasing, parallel to the increasing incidence of primary MCC. We propose a role for intracavitary BCNU wafers in the treatment of intra-axial neurometastatic MCC.

G3139 (Genasense) in patients with advanced merkel cell carcinoma

OBJECTIVES

Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine malignancy of the skin. Preclinical studies have identified up-regulation of the critical antiapoptosis gene bcl-2 in MCC. We conducted a multicenter phase II trial of the novel bcl-2 antisense agent (G3139, Genasense) in patients with advanced MCC.

METHODS

Twelve patients (9 men, 3 women) with histologically confirmed metastatic or regionally recurrent MCC were enrolled. Ten patients (83%) had received prior chemotherapy. Eight patients (67%) had Karnofsky performance status of 90 to 100. Patients received continuous IV infusion of G3139 (7 mg/kg/d) via central venous access in an outpatient setting for 14 days, followed by a 7-day rest period. Response was assessed at 6-week intervals. Patients were allowed to continue therapy until unacceptable toxicity or disease progression.

RESULTS

No objective responses were observed. The best response was stable disease in 3 patients and progressive disease in 9 patients. A median of 4 doses per patient (total 46 doses) was administered. Dose delays and/or reductions were required in 6 patients. One patient developed grade 4 lymphopenia. One patient developed grade 3 renal failure characterized by grade 3-elevated creatinine and grade 4 hyperkalemia. Other grade 3 events included cytopenia (n = 5), aspartate aminotransferase/alanine aminotranferease elevation (n = 3), hypophosphatemia (n = 2), and pain (n = 1). The most frequent grade 1 to 2 toxicities were elevated creatinine, ALT elevation, hypokalemia, lymphopenia, and fatigue.

CONCLUSIONS

Bcl-2 antisense therapy (G3139) was well tolerated among patients with advanced MCC. Although probable antitumor activity was documented in 1 patient, no objective responses per Response Evaluation Criteria in Solid Tumors criteria were observed.

Therapy of metastasized Merkel cell carcinoma with liposomal doxorubicin in combination with radiotherapy

BACKGROUND

Merkel cell carcinoma is a rare skin cancer of neuroendocrine origin, which is characterized by a high rate of recurrence, metastatic spread and mortality. Because of its rarity, evidence-based therapeutic regimens are difficult to establish. Merkel cell carcinoma is known to be both radio- and chemosensitive. Toxicity is a key factor in assessing any regimen, as the patients are usually elderly and likely to have other significant medical problems.

PATIENTS AND METHODS

We retrospectively evaluated five patients with metastatic Merkel cell carcinoma to see if liposomal doxorubicin (Caelyx) or Myocet) in combination with radiotherapy exhibited clinical anti-tumoral effects accompanied by acceptable side effects.

RESULTS

The outpatient chemotherapy regimen was tolerated without major side effects and produced good response rates. All patients achieved at least tumor stabilization; four of five had a partial remission. Effects of therapy were usually seen in the first cycle of therapy but the responses were of short duration with an average interval of two months until progression.

CONCLUSIONS

As combined radiochemotherapy with liposomal doxorubicin is well tolerated even in older patients with other illnesses and can be given on an outpatient basis, it is an attractive option for metastatic Merkel cell carcinoma. Based on response rate or overall survival, it offers no advantages compared to polychemotherapy.

Merkel cell carcinoma of the face: an analysis of 16 cases in the Japanese

BACKGROUND

There is no agreement regarding a staging system and optimal treatment of Merkel cell carcinoma. Some centres have reported results from larger series of patients, but these do not include Asian or Japanese centres.

OBJECTIVE

The purpose of this study was to retrospectively review our experience with the surgical treatment of MCC of the face in the Japanese and to study its management and outcome using the staging system described by Clark et al.

METHODS

We report our experiences with 16 cases between 1991 and 2004. Patients and tumour characteristics, treatment variables and outcome were analysed.

RESULTS

The follow-up periods ranged from 1 to 180 months. The average was 32.6 months and the median was 17.5 months. The relapse-free survival for all patients was 51% at 2 years. The relapse-free survival was 80% for the patients with Stage I and 33% with Stage II at 2 years.

CONCLUSION

This staging system was suggested to reflect prognosis although the number of patients in this series was small. Sentinel lymph node biopsy should be considered to determine the accurate nodal staging, and patients with MCC of the head and neck may be treated according to the revised staging system by Clark et al.

Cisplatin-based chemotherapy for merkel cell carcinoma of the skin

PURPOSE

Merkel cell carcinoma (MCC), a rare tumor of the skin with aggressive behavior, is usually fatal when advanced disease is present. The role of chemotherapy (CT) in the treatment of patients with MCC is unclear.

METHODS

Over 15 years, 9 patients with locally advanced or metastatic disease were treated with carboplatin (CBDCA) (300 mg/m(2) of AUC 5 on Day 1) and etoposide (VP-16) (100 mg/m(2) on Days 1-3) every 3 weeks. As second-line CT, cisplatin (CDDP) (60-100 mg/m(2)), ifosfamide (IFO) (3-5 g/m(2)) and epirubicin (EPI) (30-50 mg/m(2)) were utilized.

RESULTS

Of the 3 patients who received adjuvant therapy, one achieved complete response after 108+ months with second-line chemotherapy and radiotherapy, despite a brief relapse; 2 patients remain disease-free after 84+ and 108+ months. Of the 6 patients with locally advanced or metastatic disease who were treated with first-line chemotherapy, one (16.6 percent) achieved a complete response and 3 (50 percent) achieved partial response, for an overall response rate of 66.6 percent. Two patients (one with complete and one with partial response) received subsequent radiotherapy, following which complete response was achieved. Of the 2 complete responders, one patient remains disease-free after 56+ months. The median overall survival from the time of initial diagnosis for the whole group was 56 months (range 15-114 months); the median overall survival from the initiation of chemotherapy was 18 months (range 6-108+). Local recurrences and soft tissue metastases responded better than visceral metastases. Patients with partial response and no response had rapid disease progression and fatality, despite second-line chemotherapy and/or radiotherapy.

CONCLUSION

MCC appears to be chemosensitive but can progress rapidly with fatal outcomes. Although the rarity of these tumors precludes randomized trials, a common treatment plan should be utilized by those treating MCC. This may allow some conclusions regarding the optimum treatment of patients with MCC to be drawn in the future.

Merkel cell carcinoma: a report of 34 cases and literature review

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer, with unclear histogenesis. To date there is no consensus on the optimal treatment of this neoplasm, with controversy surrounding the use of radiotherapy and chemotherapy. There are also limited data on biological behaviour and prognosis, with reported survival ranging from 31% at three years to 74% at five years.

METHOD

The medical records of 34 patients with a diagnosis of primary MCC, treated at two NHS trusts in Birmingham and Coventry, were reviewed. An extensive review of the English literature was also performed.

RESULTS

MCC occurred predominantly in Caucasians (97%) with a mean age of 75 years. Identified risk factors were a previous history of SCC (37%), BCC (18%) and AK (20%). Ten percent of patients showed evidence of immunocompromise. Most tumours were located on the extremity, where they reached a mean size of 2.1cm. Fifty percent had regional metastasis during the course of their disease. A sub group analysis of the excision margins showed that a 2-cm excision margin, extending to the deep fascia, resulted in a 50% incomplete excision rate and a 33% local recurrence rate. In contrast a 3-cm margin including deep fascia resulted in no incomplete excisions and a 10.5% local recurrence rate Prognosis was poor with a 40% 3-year survival. Combining the data from two trusts has produced a relatively large series and highlighted differences in patient characteristics and management between the units. We advocate a 3-cm excision margin, including fascia wherever possible, combined with post-operative radiotherapy to offer the best chance of local control. Survival is fairly dismal and in keeping with the aggressive nature of this tumour. The respective roles of radiotherapy and chemotherapy remain controversial.

Merkel cell carcinoma--current therapeutic options

Merkel cell carcinoma (MCC) is a rare, highly malignant skin tumour of neuroendocrine origin that occurs predominantly in elderly people in sun-exposed areas. It exhibits high levels of radiosensitivity and chemosensitivity both in vivo and in vitro. A variety of adverse prognostic factors have been identified which allow more aggressive therapy to be delivered to patients who are at higher risk of recurrence. The most powerful prognostic factor is the presence of nodal secondaries. Local disease should be excised, but there is some controversy over how wide the margins should be. Wide resection margins are not required provided postoperative radiotherapy is used. In the event of inoperable disease, patient refusal of surgery or frailty, radiotherapy can be used as the sole treatment modality, with a high likelihood of achieving local control. Patients with involved nodes have a higher risk of distant disease. Traditionally, involved nodes have been managed with resection but, currently, there are protocols exploring the use of synchronous chemoradiotherapy as definitive treatment. Although adjuvant chemotherapy has been used in this setting to reduce the risk of distant metastases, its role still remains under investigation. The presence of distant disease carries a grave outlook with responses to chemotherapy occurring frequently, albeit of short duration.

Is there a diminishing role for surgery for Merkel cell carcinoma of the skin? a review of current management

Merkel cell carcinoma is a highly malignant skin tumour that must be managed in a multidisciplinary forum. Excisional biopsy of the primary is recommended and this should be followed by postoperative radiotherapy to the primary site, in-transit areas and the draining lymph nodes. The tumour is quite radiosensitive and radiation doses of the order of 50 Gy offer high levels of local control. Resection margins of 3 cm are not required provided postoperative radiotherapy is used. In the event of inoperable disease, patient refusal of surgery or a frail patient, radiotherapy should be used as the sole treatment modality, with high likelihood of achieving local control. Patients with involved nodes have a higher risk of distant disease. Traditionally, involved nodes have been managed with resection but, currently, there are protocols exploring the use of synchronous chemoradiotherapy as definitive treatment. Although adjuvant chemotherapy has been used in this setting to reduce the risk of distant seeding, the benefits at this stage have not been confirmed conclusively. The presence of distant disease carries a grave outlook and responses to chemotherapy occur frequently, but are usually shortlived.

Transient complete remission of metastasized Merkel cell carcinoma by high-dose polychemotherapy and autologous peripheral blood stem cell transplantation

Merkel cell carcinoma (MCC) is a rare cutaneous tumour with neuroendocrine differentiation. Metastasis occurs preferentially to regional lymph nodes but distant and multiple visceral metastases may occur. Chemotherapy has been performed with a variety of protocols based largely on agents active in small-cell lung cancer. Owing to the rarity of MCC, there is no standard protocol for the treatment of metastatic disease. We report a 59-year-old patient with systemic metastatic MCC. After diagnosis of distant metastases, first-line polychemotherapy (cisplatin 80 mg m(-2), doxorubicin 50 mg m(-2), etoposide 300 mg m(-2) and bleomycin 30 mg) was administered four times at 3-weekly intervals and resulted in partial remission of metastases. Subsequently, high-dose chemotherapy according to the PEI regimen (ifosfamide 12 g m(-2), carboplatin 900 mg m(-2) and etoposide 1500 mg m(-2)) was applied, followed by autologous blood stem cell transplantation (ABSCT). This protocol resulted in a complete remission that lasted for 6 months. This is the first report on a complete remission of metastatic MCC after high-dose polychemotherapy and ABSCT. High-dose chemotherapy might be a therapeutic option in chemosensitive metastatic MCC, and further evaluation is warranted.

Merkel cell carcinoma of the skin

BACKGROUND

Neuroendocrine/Merkel cell carcinoma (MCC) of the skin is an uncommon tumour. Currently, there are only limited data available on the natural history, prognostic factors, and patient management of MCC.

OBJECTIVES

To review our experience and build the largest database from the literature.

METHODS

Twenty-eight cases from the London Regional Cancer Center were combined with 633 cases obtained from the literature searched in English, French, German, and Chinese for the years 1966 to 1998. The database included age, sex, initial disease status at presentation to the clinic, site of primary, any coexisting disease, any previous irradiation, sizes of primary/nodal/distant metastases, management details, and final disease status. A new modified staging system was used: stage Ia (primary disease only, size > 2 cm), stage Ib (primary disease only, size > 2 cm); stage II (regional nodal disease), and stage III (beyond regional nodes and/or distant disease).

RESULTS

Age > 65 years, male sex, size of primary > 2 cm, truncal site, nodal/distant disease at presentation, and duration of disease before presentation (< or =3 months) were poor prognostic factors. Surgery was the initial treatment of choice and it significantly improved overall survival (p =.004).

CONCLUSIONS

We identified poor prognostic factors that may necessitate more aggressive treatment. The suggested staging system, incorporating primary tumour size, accurately predicted outcomes.

The Merkel cell carcinoma: survival and oncogene markers

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and malignant tumour. Survival data and prognostic factors are scarce.

AIM

To investigate the usefulness of biological markers to predict the prognosis for these aggressive tumours.

METHODS

C-myc oncoprotein and proliferation was analysed in specimens from 13 patients with MCC, treated between 1983 and 1997. The average age at presentation was 68.3 years. Overall follow-up ranged from 14 to 158 months, with a mean of 68.2 months. Specimens were analysed by immunohistochemistry for proliferation (mib-1) and flow cytometry for oncogene activity (c-myc).

RESULTS

The median positivity was 52% for the c-myc oncogene and 50% for proliferation, but these did not correlate to survival as analysed by the Kaplan-Meier method. Other parameters such as median age at presentation, sex, site of tumour and adjuvant radiotherapy were also analysed, but none were found to be significant.

CONCLUSIONS

This study showed that neither c-myc oncogene activity or mitotic index in MCC can be related to patient survival.

Chemotherapy in neuroendocrine/Merkel cell carcinoma of the skin: case series and review of 204 cases

PURPOSE

To study the use of chemotherapy for Merkel cell carcinoma (MCC) of the skin.

PATIENTS AND METHODS

Twenty-five cases of MCC were treated at the London Regional Cancer Center between 1987 and 1997. Thirteen cases treated with chemotherapy were reviewed with 191 cases from the literature.

RESULTS

At presentation, 24 patients had localized skin lesions (stage I) and one had locoregional involvement (stage II). Among the nine cases with recurrent nodal disease, six had chemotherapy as a component of salvage treatment. They were all free of disease at a median of 19 months (range, 12 to 37 months). In contrast, two patients who had salvage radiotherapy alone died of disease. Overall survival (OS) and disease-free survival (DFS) were 59% and 43%, respectively, at two years. Median OS and DFS were 29 months (range, 1 to 133 months) and 9 months (range, 1 to 133 months), respectively. Nodal disease developed in 12 (50%) of 24 patients with stage I disease, and distant metastases developed in six (25%) of 24. Including those from the literature, there were 204 cases treated with chemotherapy. Cyclophosphamide/doxorubicin (or epirubicin)/vincristine combination +/- prednisone was the most commonly used chemotherapy regimen (47 cases), with an overall response rate of 75.7% (35.1% complete, 35. 1% partial, and 5.4% minor responses). Etoposide/cisplatin (or carboplatin) was the next most commonly used regimen (27 cases), with an overall response rate of 60% (36% complete and 24% partial responses). The difference in response rate was not statistically significant (P =.19). Among the 204 cases, there were seven (3.4%) toxic deaths.

CONCLUSION

Chemoradiation for locally recurrent or advanced disease may be an option for patients with a good performance status.

Bcl-2 antisense oligonucleotides (G3139) inhibit Merkel cell carcinoma growth in SCID mice

Merkel cell carcinoma was first described in 1972 by Toker and is an aggressive neuroendocrine skin tumor with a high metastatic potential. Merkel cell carcinoma is thought to derive from the neuroendocrine (Merkel) cells of the skin, although in contrast to fetal and especially adult Merkel cells, Merkel cell carcinomas express high levels of the Bcl-2 oncoprotein. Bcl-2 is capable of blocking programmed cell death and has been shown to play an important role in normal cell turnover, tumor biology, and chemoresistance. High Bcl-2 expression leading to prolonged survival of cells may therefore be of importance in the biological and clinical characteristics of Merkel cell carcinoma. In a SCID mouse xenotransplantation model for human Merkel cell carcinoma, we investigated the influence of the bcl-2 antisense oligonucleotide G3139 (Genta) on tumor growth in comparison with control oligonucleotides or cisplatin. Bcl-2 antisense treatment, targeting the first six codons of the bcl-2 mRNA, resulted in either a dramatic reduction of tumor growth or complete remission, whereas reverse sequence and two-base mismatch control oligonucleotides or cisplatin had no significant antitumor effects compared with saline-treated controls. Apoptosis was enhanced 2.4-fold in the bcl-2 antisense treated tumors compared with the saline-treated group, and no other treatment showed a comparable increase in apoptosis. Our findings suggest that bcl-2 antisense treatment may be a novel approach to improve treatment outcome of human Merkel cell carcinoma.

Chemotherapy for patients with locally advanced or metastatic Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a highly malignant skin neoplasm. Regional lymph node and distant metastasis occur in 20-52% of patients. The role of chemotherapy in the treatment of patients with this rare tumor is unclear.

METHODS

An exhaustive analysis of the literature (1980-1995) describing chemotherapy for patients with locally advanced or metastatic MCC was performed. All available published medical records (n = 101 patients) were entered in a database. In addition, data on six additional patients given chemotherapy during this time frame in Lyon, France, were included in the database.

RESULTS

For the 107 patients, the overall objective response rate to first-line chemotherapy was 61% (61 of 101 evaluable patients). The response rate was 57 % (41 of 72) for patients with metastasis and 69% (20 of 29) for patients with locally advanced tumors. No clinical parameter was found to be correlated to response to chemotherapy. A high rate of toxic death during first-line treatment (n = 7.7%) was reported for these patients. The median overall survival from the date of chemotherapy initiation was 9 months for patients with metastasis and 24 months for patients with locally advanced tumors. The projected overall survival at 3 years was 17% for patients with metastasis and 35% for patients with locally advanced tumors. Progression after first-line chemotherapy was associated with significantly worse survival for patients with metastasis. Rates of response to second-line (n = 33) and third-line (n = 10) chemotherapy were 45% and 20%, respectively.

CONCLUSIONS

MCC is chemosensitive but rarely chemocurable in patients with metastasis or locally advanced tumors. A high incidence of toxic death due to chemotherapy is reported in the literature.

Surgical management of Merkel cell carcinoma

OBJECTIVES

To characterize the natural history of Merkel cell carcinoma (MCC) and to analyze the influence of patient, tumor, and treatment-related variables on survival and recurrence.

SUMMARY BACKGROUND DATA

Approximately 425 cases of MCC have been described in the literature. This study represents the largest experience reported.

METHODS

A review was performed of patients who had been treated at Memorial Sloan-Kettering Cancer Center for MCC between 1969 and 1996. Follow-up data were available for 102 of the 109 (94%) patients identified.

RESULTS

The overall 5-year disease-specific survival rate was 74%. The median follow-up was 35 months. For all patients, the only independent predictor of survival was the tumor stage at presentation. For patients with stage I disease, the tumor size at presentation was also an independent predictor of survival. Recurrence of disease occurred in 55 patients (55%), and the most common site of first recurrence was within the draining lymph nodes (n = 35). Elective lymph node dissection was the only parameter independently predictive of improved relapse-free survival. The overall disease-specific survival rate after recurrence was 62%. Predictors of improved disease-specific survival after recurrence included nodal as compared to local or distant recurrence, the ability to render the patient free of disease after recurrence, and a disease-free interval of >8 months.

CONCLUSION

The prognosis for patients with MCC is favorable, and even after recurrence the majority of patients experience long-term survival. Incorporation of size into the staging system more accurately predicts survival in patients with stage I disease. Although elective lymph node dissection decreased the rate of recurrence, it was not associated with improved overall survival.

The role of radiation therapy and chemotherapy in the treatment of Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma is a rare and highly aggressive skin tumor. The purpose of this study was to determine the role of radiation therapy and chemotherapy in the treatment of patients with Merkel cell carcinoma.

METHODS

A retrospective analysis of 27 patients treated at Rabin Medical Center in Israel is presented, focusing on the treatment details. Data for 40 patients (the authors' 27 patients and an additional 13 patients from the Israeli Cancer Registry), were analyzed for prognostic factors using univariate and multivariate analyses.

RESULTS

Univariate analyses revealed regional lymph node involvement and the coexistence of a second primary tumor as unfavorable prognostic factors. On multivariate analysis, only lymph node involvement showed borderline statistical significance. Radiation therapy was highly effective when given as consolidation after surgery or chemotherapy. In 11 patients irradiated effectively, only 1 (9%) in-field recurrence occurred. Radiation therapy yielded responses in 15 of 15 measurable sites (5 complete responses and 10 partial responses). Chemotherapy produced responses in 18 of 26 patients (69%), mostly complete (41%). However, in the absence of radiation therapy, the responses were short lived.

CONCLUSIONS

These data support the use of combined treatment with chemotherapy followed by radiation therapy for patients with advanced locoregional Merkel cell carcinoma. In patients with metastatic disease, chemotherapy as well as radiotherapy can provide effective palliation. Further large scale investigations are warranted to confirm this approach.

Merkel cell carcinoma: report of ten cases with emphasis on clinical course, treatment, and in vitro drug sensitivity

BACKGROUND

Merkel cell carcinoma (MCC) is an uncommon primary neuroendocrine skin tumor most often seen in the elderly. The clinical course varies. Treatment is controversial and few data on drug sensitivity are available.

OBJECTIVE

We evaluated the clinical course and treatment of 10 MCC patients and determined MCC chemosensitivity.

METHODS

Clinical records as well as laboratory and histopathologic data from 10 patients with MCC treated in our department were examined. Chemosensitivity to various chemotherapeutic agents and interferons of MCC cells from four patients was determined in a soft agar clonogenic assay.

RESULTS

MCC behaved as an aggressive tumor with early and frequent local relapses (4 of 10 patients at a 2.2-month average), regional (4 of 10 patients at 2.5 months), and distant metastases (5 of 10 patients 9.6 months after excision of the primary tumor). In all but one patient, regional metastases preceded distant ones. Metastatic spread was associated with an average survival of 21 months from the initial diagnosis. Long-term survival (53+ and 65+ months) was observed in two women. Wide excision of the primary tumor, alone or combined with adjuvant chemotherapy and radiotherapy, was the most effective treatment. In advanced disease, chemotherapy and radiotherapy were not able to induce long-term remission. In vitro assays for MCC drug sensitivity revealed cisplatin, doxorubicin, and vindesine to be the most active.

CONCLUSION

MCC has a poor prognosis in advanced stages; therefore the primary tumor should be aggressively treated. The in vitro clonogenic assay may help to identify the chemosensitivity profile of MCC and to optimize chemotherapy protocols.