Merkel cell polyomavirus-specific immune responses in patients with Merkel cell carcinoma receiving anti-PD-1 therapy

BACKGROUND

Merkel cell carcinoma (MCC) is an aggressive skin cancer that frequently responds to anti-PD-1 therapy. MCC is associated with sun exposure and, in 80% of cases, Merkel cell polyomavirus (MCPyV). MCPyV-specific T and B cell responses provide a unique opportunity to study cancer-specific immunity throughout PD-1 blockade therapy.

METHODS

Immune responses were assessed in patients (n = 26) with advanced MCC receiving pembrolizumab. Peripheral blood mononuclear cells (PBMC) were collected at baseline and throughout treatment. MCPyV-oncoprotein antibodies were quantified and T cells were assessed for MCPyV-specificity via tetramer staining and/or cytokine secretion. Pre-treatment tumor biopsies were analyzed for T cell receptor clonality.

RESULTS

MCPyV oncoprotein antibodies were detectable in 15 of 17 (88%) of virus-positive MCC (VP-MCC) patients. Antibodies decreased in 10 of 11 (91%) patients with responding tumors. Virus-specific T cells decreased over time in patients who had a complete response, and increased in patients who had persistent disease. Tumors that were MCPyV(+) had a strikingly more clonal (less diverse) intratumoral TCR repertoire than virus-negative tumors (p = 0.0001).

CONCLUSIONS

Cancer-specific T and B cell responses generally track with disease burden during PD-1 blockade, in proportion to presence of antigen. Intratumoral TCR clonality was significantly greater in VP-MCC than VN-MCC tumors, suggesting expansion of a limited number of dominant clones in response to fewer immunogenic MCPyV antigens. In contrast, VN-MCC tumors had lower clonality, suggesting a diverse T cell response to numerous neoantigens. These findings reveal differences in tumor-specific immunity for VP-MCC and VN-MCC, both of which often respond to anti-PD-1 therapy.

A case report of eyelid Merkel cell carcinoma occurring under treatment with nivolumab for a lung adenocarcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a rare neuroendocrine malignancy of the skin characterized by high aggressiveness. Four main factors are implicated in its development: immunosuppression, ultraviolet radiation, age and the Merkel cell polyomavirus (MCPyV). In recent years, immune checkpoint inhibitors have shown clinical activity in MCC treatment.

CASE PRESENTATION

We report the case of an 82-year-old man with a lung adenocarcinoma diagnosis, who underwent immunotherapy with nivolumab as second-line treatment. Seven months after the diagnosis of lung cancer during the nivolumab treatment, the patient developed an eyelid MCC, initially misdiagnosed as a chalazion. A palliative radiotherapy was performed with clinical benefit. After a total of seven cycles of nivolumab, computed tomography showed a lung and cerebral disease progression. In addition, clinical conditions worsened leading to the patient's death 13 months after the initial lung cancer diagnosis.

CONCLUSIONS

Cases of co-occurrence of MCC and non-small cell lung cancer (NSCLC) have rarely been reported. Interestingly, common risk factors may be postulated for both cancers. Considering the rarity of this adverse event, its short-term temporal relation with the administration of the drug, which makes a relation improbable, and the coexistence of other risk factors, which may provide plausible explanations, it is possible to conclude according to the WHO Adverse Reaction Terminology that a causal relation between the occurrence of this serious adverse event and the exposure to the drug is unlikely. However, the case deserves to be reported in the literature.

Venous thromboembolism leading to diagnosis of de novo malignancy in an organ transplant recipient

We report the case of a patient with remote orthotopic liver transplant who was ultimately diagnosed with Merkel cell carcinoma following admission for initial venous thromboembolism. Additionally, we review pertinent literature related to the risk of skin cancer in solid organ transplant recipients and discuss the importance of yearly skin exams in this patient population.

Merkel Cell Carcinoma in the Age of Immunotherapy: Facts and Hopes

Merkel cell carcinoma (MCC) is a rare (∼2,000 U.S. cases/year) but aggressive neuroendocrine tumor of the skin. For advanced MCC, cytotoxic chemotherapy only infrequently (<10% of cases) offers durable clinical responses (>1 year), suggesting a great need for improved therapeutic options. In 2008, the Merkel cell polyomavirus (MCPyV) was discovered and is clonally integrated in approximately 80% of MCC tumors. The remaining 20% of MCC tumors have large numbers of UV-associated mutations. Importantly, both the UV-induced neoantigens in virus-negative tumors and the MCPyV T antigen oncogenes that are required for virus-positive tumor growth are immunogenic. Indeed, antigen-specific T cells detected in patients are frequently dysfunctional/"exhausted," and the inhibitory ligand, PD-L1, is often present in MCC tumors. These findings led to recent clinical trials involving PD-1 pathway blockade in advanced MCC. The combined data from these trials involving three PD-1 pathway blocking agents-avelumab, pembrolizumab, and nivolumab-indicated a high frequency of durable responses in treated patients. Of note, prior treatment with chemotherapy was associated with decreased response rates to PD-1 checkpoint blockade. Over the past year, these striking data led to major changes in advanced MCC therapy, including the first-ever FDA drug approval for this disease. Despite these successes, approximately 50% of patients with MCC do not persistently benefit from PD-1 pathway blockade, underscoring the need for novel strategies to broaden antitumor immune responses in these patients. Here, we highlight recent progress in MCC including the underlying mechanisms of immune evasion and emerging approaches to augment the efficacy of PD-1 pathway blockade. Clin Cancer Res; 24(9); 2035-43. ©2017 AACR.

CUTANEOUS POLYPOID MELANOMA OF HEAD AND NECK

Cutaneous polypoid melanoma is an uncommon subtype of malignant melanoma. The clinical behavior of this subtype has been described as aggressive. Tumors can be sessile or pedunculated. The typical patient is a younger adult. Authors have analyzed the case histories of patients with polypoid melanomas of the head and neck region treated at our clinic from 2001 to 2018. We identified 3 female patients with tumors of the neck and cheek. In contrast to other reports, all patients were older than 80-years of age. None of them had a metastatic spread at the time of diagnosis. Treatment was delayed Mohs surgery. Polypoid melanomas of the head and neck region can occur in elderly patients without an aggressive course. In those patients a number of differential diagnoses have to be considered including Merkel cell carcinoma, metatypical basal cell carcinoma, squamous cell carcinoma and tumor metastases.

Lymph Nodal Merkel Cell Carcinoma; Primary or Metastatic Disease? A Clinical Case

We report a case of Merkel cell carcinoma (MCC) presenting in the lymph nodes in the absence of a primary cutaneous site. The MCC was treated by palliative radiotherapy, which controlled the disease locally. Eight months after diagnosis a mass appeared on the ipsilateral knee; histopathological examination of this lesion confirmed the diagnosis of MCC. The patient died two months later due to the development of pulmonary metastases. Interestingly, the neoplastic tissue was confined to the regional lymph nodes for several months before the primary site appeared. Primary lymph nodal MCC is rare and the diagnosis is difficult. In our opinion the only way to make a diagnosis of primary lymph nodal MCC is by appropriate clinical follow-up.

Merkel Cell Carcinoma after Liver Transplantation: A Case Report

Background

Merkel cell carcinoma is a rare and aggressive neuroendocrine skin cancer with a very low incidence in the general population. MCC seems to be common in transplant recipients and 52 cases have been reported in the literature.

Methods and results

This report describes a Merkel cell carcinoma which developed in a liver transplant recipient. To our knowledge, this is the second such case reported, as Merkel cell carcinoma most commonly occurs after kidney and heart transplants. The treatment approach is described and the literature on the subject is reviewed.

Conclusion

There is currently no consensus regarding the optimal therapeutic approach to Merkel cell carcinoma. In transplant recipients, such tumors are more common and more aggressive but their treatment does not differ from the treatment of Merkel cell carcinomas in the general population.

Merkel cell carcinoma of the eyelid and orbit

The incidence of Merkel cell carcinoma has tended to increase worldwide in recent years. Merkel cell carcinoma is a rare tumor of the skin that occurs mainly in the sun exposed sites. The malignant reversal of Merkel cells is currently associated with an infection caused by a Merkel cell polyomavirals. In some cases, the disease may have a relatively inconspicuous clinical picture in the initial phase, which is in contrast to its extensive microscopic propagation. For this reason, the risk of late diagnosis or insufficient primary surgery is increased. The diagnostic standard is histological and, in particular, immunohistochemical examination of tumor tissue samples. Merkel cell carcinoma is a marked tendency to local recurrence and early development of metastases in regional lymph nodes, followed by generalization. The basis of treatment is radical excision of the tumor by in most cases by adjuvant radiotherapy targeted at primary place of occurrence and the area of regional draining lymph nodes. The effectiveness of different chemotherapeutic protocols in Merkel cell carcinoma is mostly low and the median survival is low. From a prognostic point of view, Merkel cell carcinoma plays the most important role of staging the tumor at the time of capture. The suspected lesions in the area around the eye, eyelid and orbit need to indicate adequate therapeutic approach that the detection of the disease at the earliest stage. The authors describe the clinical experience in 2 patients with Merkel cell carcinoma of the eyelid and orbit. Key words: eyelid tumors, tumors of the orbit, Merkel cell carcinoma.

Merkel cell carcinoma with seborrheic keratosis: A unique association

Merkel cell carcinoma (MCC) is a rare, clinically aggressive neuroendocrine carcinoma of the skin; MCC is 40 times less common as compared to melanoma. The most frequently reported sites have been the head and neck, extremities, and trunk. Potential mimics include malignant melanoma, lymphoma, or metastatic small cell (neuroendocrine) carcinomas. Histopathology of MCC resembles small cell carcinoma both morphologically and on IHC. The possible cell of origin was proposed as the Merkel cell, which functions as a mechanoreceptor. It has a high chance of local recurrence, regional and distant spread. In recent times, Merkel cell polyomavirus has been implicated as the causative agent for this tumor. The same agent has a reported etiologic association with other skin lesions, including seborrheic keratosis.

Merkel cell carcinoma: Epidemiology, pathogenesis, diagnosis and therapy

Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer with a neuroendocrine phenotype. Incidence varies according to the geographic regions but is overall increasing. Different risk factors have been identified namely advanced age, immunosuppression, and ultraviolet light exposure. An association between MCC and polyomavirus infection is known. However, the exact mechanism that leads to carcinogenesis is yet to be fully understood. Surgery when feasible is the recommended treatment for localized disease, followed by adjuvant radiation or chemoradiation. In the metastatic setting, chemotherapy has been the standard treatment. However, two recently published trials with immune checkpoint inhibitors in first and second line showed promising results with a tolerable safety profile and these might become the standard therapy shortly. Somatostatin receptors are expressed in many MCC but such expression is not associated with disease severity. Presently there are no biomarkers predictive of response that could help to better select patients to these new therapies, and additional research is essential.

A rare case of Merkel cell carcinoma presenting as a giant intra-thoracic mass: A case report and review of the literature

RATIONALE

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine-derived cutaneous cancer. Ectopic or single metastatic MCC located in thorax is extremely rare; meanwhile, its definite management has not been elucidated yet.

PATIENT CONCERNS

A 64-year-old female patient with a giant mass located in her left thorax was presented for stuffy pain of left chest for 6 months and fever for half a month. She underwent radical resection of vulvar MCC 10 years ago.

DIAGNOSES

Computed tomography (CT)-guided biopsy of the intrathoracic mass revealed a diagnosis of MCC, without synchronous urogenital lesions on pelvic CT images.

INTERVENTIONS

This bulky tumor was completely resected via thoracotomy, along with the adjacent pulmonary lobe, pericardium, pleura, and diaphragm.

OUTCOMES

The patient survived without local-regional recurrence or distant metastasis during the follow-up of 1 year up to now.

LESSONS

Ectopic or single metastatic MCC should be considered in the differential diagnosis of intrathoracic tumors, especially in patients with a history of MCC. Besides, a timely surgery combined with chemotherapy is effective for this disease.

Aggressive Merkel cell carcinoma in a liver transplant recipient

Merkel cell carcinoma (MCC) is a rare aggressive cutaneous tumor that commonly occurs in sun-exposed sites. It has a tendency for rapid growth, local recurrence, lymph node invasion, and distant metastases. Risk factors include immunosuppression, advanced age, exposure to UV radiation, and infection with the Merkel cell polyomavirus. We report a case of a 67-year-old woman with rapidly aggressive MCC 6 years after liver transplantation.

Age and Gender Associations of Virus Positivity in Merkel Cell Carcinoma Characterized Using a Novel RNA In Situ Hybridization Assay

Purpose: Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine tumor of the skin. Merkel cell polyomavirus (MCPyV) plays an oncogenic role in the majority of MCCs. Detection of MCPyV in MCCs has diagnostic utility and prognostic potential. We investigated whether RNAscope, an RNA in situ hybridization (ISH) assay for detection of RNA transcripts in tissues, is useful for MCPyV detection.Experimental Design: We applied an RNAscope probe targeting MCPyV T antigen transcripts on tissue microarrays (TMA) and whole-tissue sections encompassing 87 MCCs from 75 patients, 14 carcinomas of other types, and benign tissues. For comparison, qPCR was performed on 57 cases of MCC from 52 patients.Results: RNA-ISH demonstrated the presence of MCPyV in 37 of 75 cases (49.3%). Notably, tumors from younger patients (<73 years) had a significantly higher virus positivity than those from elderly patients (≥73 years; 64.9% vs. 34.2%, P = 0.011). Female patients had a higher positive rate of MCPyV than male patients (66.7% vs. 39.6%, P = 0.032). Data from both RNA-ISH and qPCR were available for 57 samples. Considering MCPyV qPCR as the gold standard for determining MCPyV status, RNAscope had 100% sensitivity and 100% specificity. There was a strong correlation between qPCR copy number and RNA-ISH product score (Spearman correlation coefficient R² = 0.932, P < 0.0001).Conclusions: RNA-ISH is comparably sensitive to qPCR for detection of MCPyV and allows for correlation with tissue morphology. This study also reveals a significant association between age, gender, and MCPyV positivity. Clin Cancer Res; 23(18); 5622-30. ©2017 AACR.

Viral oncoprotein antibodies as a marker for recurrence of Merkel cell carcinoma: A prospective validation study

BACKGROUND

Merkel cell carcinoma (MCC) is an aggressive skin cancer with a recurrence rate of >40%. Of the 2000 MCC cases per year in the United States, most are caused by the Merkel cell polyomavirus (MCPyV). Antibodies to MCPyV oncoprotein (T-antigens) have been correlated with MCC tumor burden. The present study assesses the clinical utility of MCPyV-oncoprotein antibody titers for MCC prognostication and surveillance.

METHODS

MCPyV-oncoprotein antibody detection was optimized in a clinical laboratory. A cohort of 219 patients with newly diagnosed MCC were followed prospectively (median follow-up, 1.9 years). Among the seropositive patients, antibody titer and disease status were serially tracked.

RESULTS

Antibodies to MCPyV oncoproteins were rare among healthy individuals (1%) but were present in most patients with MCC (114 of 219 patients [52%]; P < .01). Seropositivity at diagnosis independently predicted decreased recurrence risk (hazard ratio, 0.58; P = .04) in multivariate analyses adjusted for age, sex, stage, and immunosuppression. After initial treatment, seropositive patients whose disease did not recur had rapidly falling titers that became negative by a median of 8.4 months. Among seropositive patients who underwent serial evaluation (71 patients; 282 time points), an increasing oncoprotein titer had a positive predictive value of 66% for clinically evident recurrence, whereas a decreasing titer had a negative predictive value of 97%.

CONCLUSIONS

Determination of oncoprotein antibody titer assists in the clinical management of patients with newly diagnosed MCC by stratifying them into a higher risk seronegative cohort, in which radiologic imaging may play a more prominent role, and into a lower risk seropositive cohort, in which disease status can be tracked in part by oncoprotein antibody titer. Cancer 2017;123:1464-1474. © 2016 American Cancer Society.

[Merkel cell carcinoma of the facial skin. Cases presentation and general rules of treatment]

Merkel cell carcinoma is an aggressive, malignant, neuroendocrine tumor of the skin. The aim of the study is to present the clinical pictures, methods and results of treatment of MCC in the Clinic of Maxillofacial Surgery in Rzeszow in years 2003-2010. Changes were located on the skin of the face of four patients. All patients were treated surgically, the primary change was removed. Recurrence after surgical treatment was observed in all patients. The observations confirmed the data from the literature about the incidence of MCC over 75 years of age, aggressiveness and difficulties in treatment of this disease.

Merkel cell carcinoma in a vein graft donor site

The development of malignancies in graft donor sites is rare and may be caused by de novo malignancies as well as metastatic and iatrogenic spread. Malignancies in graft donor sites are distinguished from Marjolin ulcers by some investigators because they occur in healed surgical wounds rather than in chronic wounds or unstable scars and tend to occur sooner after injury. We present a unique case of Merkel cell carcinoma (MCC) developing in a vein graft donor site 18 years after vein harvesting.

Merkel cell carcinoma: a review

Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor of unknown origin that usually presents in the elderly population. A novel polyomavirus has been associated with a large percentage of tumors. Immune response plays an important role in pathogenesis of MCC. This article reviews the history, pathogenesis, presentation, and treatment of MCC. Future treatments also are discussed briefly.

Merkel cell carcinoma of the eyelid. A series of 5 cases and review of the literature

OBJECTIVE

Presentation of 5 clinical cases of Merkel cell carcinoma of the eyelid, highlighting the clinical, histopathological, management, and monitoring features. Review of related literature.

METHODS

Retrospective review of clinical records and telephone interview of the 5 patients treated for Merkel cell carcinoma between 2006 and 2013, in the Orbit and Oculoplastic Department, Clinical Hospital of the University of Chile.

RESULTS

Five patients (2 men, 3 women); 79.2 years (range 64-94 years), with a mean onset of 10 weeks (range 5-16 weeks), tumour size reaching a mean of 2.5×2×2.1cm at the time of surgery. Described as a nodular mass, exophytic, solid, reddish coloured. With no infiltrated lymph nodes or metastases in the first match. Staging as T2N0M0, after the first surgery with oncological criteria. Two lymph node recurrences detected during monitoring. Distant metastasis was found in one patient. The histopathological diagnosis was confirmed by immunohistochemical study of the biopsy. The surgical strategy was full excision, control of surgical margins in the intraoperative period, and eyelid reconstruction with Hughes flap, Cutler/Beard flap or primary closure, depending on the case.

CONCLUSIONS

Early diagnosis, wide excision of the tumour with intraoperative control of clear margins with conventional or Mohs surgery, and proper eyelid reconstruction are adequate for a good survival in elderly patients with this eyelid tumour. The study of sentinel lymph node biopsy in primary intervention is recommended; with subsequent radiotherapy to decrease the recurrence and increase survival.

Unexpected maspin immunoreactivity in Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare but aggressive cutaneous neuroendocrine tumor, which multifactorial etiopathogenesis seems to be related to ultraviolet radiation, Merkel cell polyomavirus (MCV), and immunosuppression. In this paper, we present three cases of diagnosed MCC in apparently healthy Caucasians, two of them located in a sun-exposed area. They represented 0.25 % of all cutaneous malignant tumors diagnosed in our department. In the first case, MCC was diagnosed in the frontal region of a 67-year-old male, the second case was located in the right thigh of a 55-year-old female, whereas the third case involved the upper trunk of a 62-year-old female. All of these cases were diagnosed in the pT1 stage, having a diameter smaller than 2 cm, but the invasion depth involved the hypodermis. Microscopically, they consisted of small cells with round-oval nuclei having finely dispersed chromatin and well-defined nucleoli. Immunohistochemically, the tumor cells displayed positivity for keratin 20 and neuroendocrine markers, being negative for keratin 7 and S100 protein. Maspin immunoreactivity was seen in cases 1 and 3. Not one of the cases expressed DOG-1 or even TTF-1. Furthermore, this is the first report in literature about maspin positivity in MCC that might be related to sun exposure.