Modern management of Merkel cell carcinoma:

Islet-1 promotes the proliferation and invasion, and inhibits the apoptosis of A375 human melanoma cells

The aim of this study was to examine the effects of the insulin gene enhancer-binding protein, islet-1 (ISL1), on the proliferation, invasion and apoptosis of the human melanoma cell line, A375. An ISL1 overexpression lentiviral vector was constructed and transfected into the A375 cells. The proliferation of the A375 cells transfected with the ISL1 vector (termed A375/ISL1 cells) was examined by MTT assay, flow cytometry and TUNEL assay, and cell invasion was examined by Transwell assay. The expression levels of matrix metalloproteinase (MMP)-2 and MMP-9 were measured by qPCR and western blot analysis; the expression levels of Akt and p-Akt were measured in the cells treated with vascular endothelial growth factor (VEGF) and the PI3K/Akt inhibitor, LY294002, by western blot analysis. The optical density value of the A375/ISL1 cells was increased after 12 h of culture (P<0.001), as shown by MTT assay. The ratio of apoptotic A375/ISL1 cells was significantly decreased (P<0.001), as shown by flow cytometry and TUNEL assay. In addition, the average penetration rate of the A375/ISL1 cells significantly increased (P<0.001), as shown by Transwell assay. The expression levels of MMP-2 and MMP-9 were significantly increased in the A375/ISL1 cells, as shown by qPCR and western blot analysis (P<0.001). Moreover, treatment of the A375/ISL1 cells with VEGF for 48 h increased the expression of Akt and p-Akt compared with the control cells transfected with A375/green fluorescent protein (GFP) (P<0.05; P<0.001, respectively). In addition, in the A375/ISL1 cells treated with the LY294002 inhibitor for 24 and 48 h, the level of Akt was also found to increase compared to the control A375/GFP cells (P<0.05). On the whole, the findings of this study indicate that the overexpression of ISL1 promotes the proliferation and invasion, and inhibits the apoptosis of A375 melanoma cells. ISL1 thus plays an important role in A375 cell survival, and these effects are possibly mediate via the PI3K/Akt signaling pathway.

Merkel cell carcinoma of the head and neck: poorer prognosis than non-head and neck sites

Background:

Merkel cell carcinoma is a rare, aggressive neurocutaneous malignancy. This study investigated whether patients with Merkel cell carcinoma in the head and neck had poorer outcomes than patients with Merkel cell carcinoma located elsewhere.

Methods:

A retrospective study was performed of patients with Merkel cell carcinoma treated at the Jewish General Hospital in Montréal, Canada, from 1993 to 2013. Associations between clinicopathological characteristics and disease-free and disease-specific survival rates were examined according to the Kaplan–Meier method.

Results:

Twenty-seven patients were identified. Although basic clinicopathological characteristics and treatments were similar between head and neck and non-head and neck Merkel cell carcinoma groups, disease-free and disease-specific survival rates were significantly lower in the head and neck Merkel cell carcinoma group (log-rank test; p = 0.043 and p = 0.001, respectively). Mortality was mainly due to distant metastasis.

Conclusion:

Patients with head and neck Merkel cell carcinoma had poorer survival rates than patients with non-head and neck Merkel cell carcinoma in our study. The tendency to obtain close margins, a less predictable metastatic pattern, and/or intrinsic tumour factors related to the head and neck may explain this discrepancy.

Merkel Cell Carcinoma: When Does Size Matter for Radiotherapy?

Merkel cell carcinoma is a very aggressive, rare cancer of the skin. It has a high propensity for local, regional, and distant recurrence and has recently been associated with a viral etiology from the recently diagnosed Merkel Cell Polyoma Virus. The optimal management remains controversial. We discuss the case of a man with a 26 cm axillary lymph node metastasis of unknown primary treated with radiotherapy.

Merkel cell carcinoma: Do you know your guidelines?

BACKGROUND

Merkel cell carcinoma (MCC) is a cutaneous neuroendocrine malignancy that exhibits clinically aggressive features and is associated with a poor prognosis. The incidence of MCC seems to be increasing for reasons unknown, and is estimated to be 0.32/100,000 in the United States.

METHODS

This article will review the current literature and National Comprehensive Cancer Network practice guidelines in the treatment of MCC.

RESULTS

Resection of MCC with negative margins remains the mainstay of therapy. Positive nodal disease should be treated with neck dissection and adjuvant radiotherapy. High-risk patients should undergo adjuvant radiotherapy, which improves oncologic outcomes. The role of chemotherapy is less clear and is currently reserved for advanced-stage MCC and palliative therapy.

CONCLUSION

The pathogenesis of MCC has recently been impacted with the discovery of the Merkel cell polyomavirus (MCPyV). Research to establish targeted and immunologic therapeutic options are ongoing.

Merkel cell carcinoma: An algorithm for multidisciplinary management and decision-making

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine tumor of the skin. Therapeutic approach is often unclear, and considerable controversy exists regarding MCC pathogenesis and optimal management. Due to its rising incidence and poor prognosis, it is imperative to establish the optimal therapy for both the tumor and the lymph node basin, and for treatment to include sentinel node biopsy. Sentinel node biopsy is currently the most consistent predictor of survival for MCC patients, although there are conflicting views and a lack of awareness regarding node management. Tumor and node management involve different specialists, and their respective decisions and interventions are interrelated. No effective systemic treatment has been made available to date, and therefore patients continue to experience distant failure, often without local failure. This review aims to improve multidisciplinary decision-making by presenting scientific evidence of the contributions of each team member implicated in MCC management. Following this review of previously published research, the authors conclude that multidisciplinary team management is beneficial for care, and propose a multidisciplinary decision algorithm for managing this tumor.

Merkel cell carcinoma of the head and neck: pathogenesis, current and emerging treatment options

Merkel cell carcinoma (MCC) is a relatively uncommon, neuroendocrine, cutaneous malignancy that often exhibits clinically aggressive features and is associated with a poor prognosis. It typically presents as a painless, rapidly enlarging, dome-shaped red or purplish nodule in a sun-exposed area of the head and neck or upper extremities. Our understanding of MCC has increased dramatically over the last several years and the pathogenesis continues to be an area of active research. The etiology is likely multifactorial with immunosuppression, UV-induced skin damage, and viral factors contributing to the development of MCC. The recent discovery of Merkel cell polyomavirus has allowed for at least one aspect of disease development to be much better understood. In most cases, treatment consists of wide local excision with adjuvant radiation therapy. The role of chemotherapeutics is still being defined. The recent advancement of knowledge regarding the pathogenesis of MCC has led to an explosion research into novel therapeutic agents and strategies. This review seeks to summarize the current body of literature regarding the pathogenesis of MCC and potential targets for future therapies.

Malignant cutaneous adnexal tumours of the head and neck: an update on management

Adnexal tumours form a heterogeneous group of relatively rare neoplasms. Many of them have a poor prognosis and treatment can sometimes be difficult and controversial. We summarise the latest publications relating to malignant cutaneous adnexal tumours of the head and neck, and give an update on their management. We discuss Merkel cell carcinoma and other rare malignant adnexal tumours including dermatofibrosarcoma protuberans and atypical fibroxanthoma.

Merkel cell carcinoma: A case of palliative upper limb amputation in a patient with refractory in-transit metastases

We report an unusual case of Merkel cell carcinoma in a 70-year-old woman with the rapid development of left upper limb in-transit and hepatic metastases. The patient had a preceding history of left-sided breast cancer. Palliative chemotherapy with carboplatin and etoposide produced a minimal response. The in-transit metastases rapidly progressed and were refractory to chemotherapy and a single fraction of palliative radiotherapy, leading to a marked impact on her quality of life, secondary to sepsis and bleeding. After lengthy discussion, she consented to an above-elbow amputation resulting in a marked improvement in her well-being. In this case, we believe that palliative amputation of the involved arm was justified and beneficial to the patient.