The natural history and management of Merkel cell carcinoma of the skin: a review of 22 patients treated at the Royal Marsden Hospital

Primary neuroendocrine neoplasms of the vulva: A review of the MITO rare cancer group

Gynecological neuroendocrine neoplasms are rare entities and can be divided into two groups: carcinoids and neuroendocrine carcinomas. Due to their rarity their management is not standardized. The aim of this work is to summarize and discuss the current literature evidence on this pathology. A scoping literature review was performed in multiple databases. Thirty-one studies were included: 30 case reports and one case series. Patients' age ranged between 28 and 92 years. Surgery was the most used treatment and the surgical approach included local excision (N = 16/31; 51.6%) with (N = 5/16; 31.25%) or without (N = 11/16; 68.75%) inguinal lymphadenectomy. Adjuvant radiotherapy was delivered in 12 (38.7%) cases; instead, platinum-based therapies were frequently used when chemotherapy was chosen for adjuvant treatment. The overall survival ranged between 20 days to 4 years. However, further research is needed; currently, multimodal approach including surgery, chemotherapy and radiotherapy appeared safe and feasible for the treatment of these rare and aggressive diseases.

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.

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.

A practical update of surgical management of merkel cell carcinoma of the skin

The role of surgeons in the treatment of Merkel cell carcinoma (MCC) of the skin is reviewed, with respect to diagnosis and treatment. Most of the data in the literature are case reports. Surgery is the mainstay of treatment. A wide local excision, with sentinel node (SLN) biopsy, is the recommended treatment of choice. If SLN is involved, nodal dissection should be performed; unless patient is unfit, then regional radiotherapy can be given. Surgeons should always refer patients for assessment of the need for adjuvant treatments. Adjuvant radiotherapy is well tolerated and effective to minimize recurrence. Adjuvant chemotherapy may be considered for selected node-positive patients, as per National Comprehensive Cancer Network guideline. Data are insufficient to assess whether adjuvant chemotherapy improves survival. Recurrent disease should be treated by complete surgical resection if possible, followed by radiotherapy and possibly chemotherapy. Generally results of multimodality treatment for recurrent disease are better than lesser treatments. Future research should focus on newer chemotherapy and molecular targeted agents in the adjuvant setting and for gross disease.

Merkel cell carcinoma with lymph node metastasis in the absence of a primary site: Case report and literature review

Merkel cell carcinoma (MCC) is a rare malignant skin neoplasm with the potential for local recurrence, spreading to regional lymph nodes (LNs) and distant metastases. Although it has been identified in various anatomical sites, LN metastatic MCC in the absence of a primary site is extremely rare. The present case reports a 54-year-old male who initially underwent histological examination of a biopsy specimen from the right inguinal LNs. A diagnosis of metastatic small cell carcinoma was made. Nine months later, this diagnosis was changed to MCC with multiple metastases following observation of a tumour mass in the right dorsal thigh. Additionally, in the present study a summary is provided of 23 published cases of MCC with initial LN metastasis in the absence of a primary site, with details of clinical characteristics, natural history and pertinent therapy of this uncommon tumour. The present patient with LN metastatic MCC in the absence of a primary site and the other reported cases demonstrate that although multimodal treatment with surgery, radiotherapy (RT) and chemotherapy provides excellent local control, local recurrence and distant metastases commonly develop in this uncommon tumour. LN metastatic MCC in the absence of a primary site is a highly malignant disease and the role of adjuvant postoperative RT and/or chemotherapy remains to be fully determined.

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.

[Management for 145 cases of Merkel cell carcinoma]

PURPOSE

Merkel cell carcinoma (MCC)/primary cutaneous neuroendocrine carcinoma is a rare and aggressive malignant tumor. Optimal therapeutic strategy has not yet been established.

PATIENTS AND METHODS

Management of 145 patients from five centres was analysed. These data included ages, pathological stages, disease sites, histological and treatment details. Cause-specific (CSS) and overall survivals (OS) were analyzed by the Log-rank and Kaplan-Meier methods.

RESULTS

Median age was 78 years (47-95.2). We experienced 37 local, 37 regional and 15 distant relapses. In case of relapse, salvage therapy has been proposed whenever the general state of health condition of patient permitted it.

CONCLUSION

Our results for the treatment of relapse encourage multidisciplinary approach. Multicenter prospective trials are still needed to clarify and validate the optimal strategy.

Multicentric cutaneous neuroendocrine (Merkel cell) carcinoma in a dog

Multicentric cutaneous neuroendocrine (Merkel cell) carcinoma was diagnosed in a 5-year-old castrated male Keeshond dog with multiple firm nodular cutaneous masses. The neoplastic tissue locally effaced the periadnexal and deep dermis and consisted of densely cellular confluent clusters of round to polygonal cells supported by a delicate fibrovascular stroma. The cells were moderately immunoreactive with chromogranin A, synaptophysin, and cytokeratin. Ultrastructurally, the cells had characteristic membrane-bound dense-core neuroendocrine granules approximately 120 nm in diameter and randomly dispersed throughout the cytoplasm. Effacement of dermal structures and multicentric distribution suggested low-grade malignant phenotype. These findings contrast with the typical benign behavior of canine cutaneous neuroendocrine tumors.

Factors influencing relapse-free survival in Merkel cell carcinoma of the lower limb--a review of 60 cases

PURPOSE

Factors affecting relapse-free survival (RFS) in patients with Merkel cell carcinoma (MCC) of the lower limb were reviewed.

METHODS AND MATERIALS

The records of 60 patients from 1986 to 2005 with a diagnosis of MCC of the lower limb or buttock were retrospectively reviewed. The patients were treated with curative intent with surgery, radiation, or chemotherapy.

RESULTS

The 5-year overall survival, disease-specific survival, and RFS were 53%, 61%, and 20%, respectively. Factors influencing RFS were analyzed using univariate analysis. It appeared that recurrent disease worsened RFS (p = 0.03) and the addition of any radiotherapy improved RFS (p <0.001), as did radiotherapy to the inguinal nodes (p = 0.01) or primary site and inguinal nodes (p = 0.003). Age, surgical margins, and stage were not statistically significant. On multivariate analysis, the only significant factor was the addition of radiotherapy (hazard ratio = 0.51 p = 0.03).

CONCLUSION

The addition of radiotherapy improves RFS compared with surgery alone. Elective treatment should be given to the inguinal nodes to reduce the risk of relapse.

Merkel cell carcinoma in a young pregnant woman

SUMMARY

We present a 27-year-old pregnant woman with Merkel cell carcinoma on the forehead. In early pregnancy, the lesion was excised as an epidermal cyst. It was only after recurrence that a diagnosis of Merkel cell carcinoma was made. Sentinel-node biopsy, excision with 2 cm margins and reconstruction with free microvascular radial forearm flap was carried out, and the patient received postoperative radiotherapy. No evidence of recurrence or disease progression was found 24 months after surgery.

A Case of Merkel Cell Carcinoma: Treated with Wide Excision and Adjuvant Radiotherapy

Merkel cell carcinoma is a rare aggressive primary cutaneous neuroendocrine skin cancer arising from the basal epidermis. Although the majority of patients with non-melanoma skin cancer are cured by local treatment, patients with Merkel cell carcinoma have a poor outcome characterized by locoregional and distant relapse. No standard treatment protocol for Merkel cell carcinoma exists. But, there is mounting evidence that combined treatment, incorporating adjuvant radiotherapy, improves the outcome (locoregional control and disease-free survival) compared with surgery alone in most patients. Herein we report a case of Merkel cell carcinoma treated with wide local excision and post-operative radiotherapy.

A comprehensive review of the treatment of Merkel cell carcinoma

Merkel cell carcinoma (MCC) is an uncommon but malignant cutaneous neuroendocrine carcinoma with a high incidence of local recurrence, regional lymph node metastases, and subsequent distant metastases. The etiology of MCC remains unknown. It usually occurs in sun-exposed areas in elderly people, many of whom have a history of other synchronous or metachronous sun-associated skin lesions. The outcome for most patients with MCC is generally poor. Surgery is the mainstay of treatment. The role of adjuvant therapy has been debated. However, data from recent development support a multimodality approach, including surgical excision of primary tumor with adequate margins and sentinel lymph node dissection followed by postoperative radiotherapy in most cases, as current choice of practice with better locoregional control and disease-free survival. Patients with regional nodal involvement or advanced disease should undergo nodal dissection followed by adjuvant radiotherapy and, perhaps, systemic platinum-based chemotherapy in most cases.

Neuroendocrine carcinoma arising in soft tissue: three case reports and literature review

Background

Neuroendocrine tumours (NET) are tumours arising from neuroendocrine cells of neural crest origin. They are characterised by the presence of neurosecretory granules which react positively to silver stains and to specific markers including neuron specific enolase, synaptophysin and chromogranin. Metastasis to the skin occurs infrequently but primary soft tissue NET is excessively rare.

Case presentation

We report our experience with 3 such cases. In the first case, the NET originated in muscle and was treated with wide surgical excision and adjuvant radiotherapy. The second case presented as a subcutaneous mass in the foot and the tumour was positive on ¹²³I mIBG scan. She has had prolonged recurrence-free survival following primary hypo-fractionated radiotherapy. In the third case, a cutaneous nodule proved to be a NET and at surgery, lymph node disease was present. He has remained disease-free after surgical excision without the need for external beam radiotherapy.

Conclusion

These tumours appear to have a good prognosis. Complete excision offers potentially curative treatment. Adjuvant radiotherapy may be helpful when the tumour margin is narrow. For patients with unresectable disease or where surgery would not be appropriate, radiotherapy appears to be an effective therapeutic option.

Merkel Cell Carcinomas

Merkel cell carcinoma (MCC) is a rare and extremely aggressive skin cancer that arises from primary neural cells. It presents most commonly in the elderly and immunocompromised patients. Pathologically, MCC should be distinguished from extrapulmonary small cell lung cancer or metastatic small cell lung cancer or a small cell variant of melanoma. The prognosis is based largely on the stage of disease at the time of presentation. Therapeutic options for MCC include wide resection with or without adjuvant radiotherapy or chemotherapy. Novel therapies based on the understanding of the molecular aspects of MCC are currently being explored.

Merkel cell carcinoma in South East Scotland, 1993– 2003

BACKGROUND AND AIMS

Merkel cell carcinoma (MCC) is a rare cutaneous malignancy. The aims of this study were to look at the incidence and distribution of MCC in a predominantly skin type I Caucasian population, review overall management of the disease and assess patient outcomes.

METHODS

Cases were identified through the regional pathology database. Twenty patients were diagnosed with MCC over a 10-year period (1993-2003) and managed at the Regional Plastic Surgery Unit at St John's Hospital, Livingston.

RESULTS

The disease incidence was found to be 0.133 per 100,000 per annum. All patients were Caucasian, seven males and 13 females (1:1.9 ratio). The mean age at presentation was 77 years (range 58-93 years). The majority of lesions were found to be stage IA (80%), located in the head and neck region. There were two cases (10%) with stage II disease and two (10%) with stage III disease (both with liver metastases) at the time of diagnosis. All patients were managed operatively. Seventeen of the 20 had wide local excisions; of the remaining three, two were only suitable for debulking procedures and one patient (stage II) had only a diagnostic biopsy, refusing intervention thereafter. One patient received adjuvant chemoradiotherapy.

CONCLUSION

Surgery remains the mainstay of treatment but adjuvant therapy, in particular chemotherapy, is problematic in a frail, elderly population.

Merkel cell cancer of the skin

Merkel cell carcinoma (MCC) is a rare malignant cutaneous tumor of the elderly with rapidly growing skin nodules found predominantly on sun-exposed areas of the body. The vast majority of patients present with localized disease, while up to 30% have regional lymph node metastases. Despite local excision and the incidence of local recurrence, regional lymph node metastases and distant metastases is high and usually occurs within 2 years of primary diagnosis. The optimal treatment for patients with MCC remains unclear. The best outcome is achieved with multidisciplinary management including surgical excision of primary tumor with adequate margins and post-operative radiotherapy (RT) to control local and regional disease. Patients with regional nodal metastases should be treated with lymph node dissection plus RT. Adjuvant chemotherapy (CT) should be considered as part of the initial management. In case of metastatic disease CT based on regimens used for small-cell lung cancer is the standard treatment of care.

Merkel cell carcinoma

Background

Merkel cell carcinoma (MCC) is an unusual primary neuroendocrine carcinoma of the skin. MCC is a fatal disease, and patients have a poor chance of survival. Moreover, MCC lacks distinguishing clinical features, and thus by the time the diagnosis is made, the tumour usually have metastasized. MCC mainly affects sun-exposed areas of elderly persons. Half of the tumours are located in the head and neck region.

Methods

MCC was first described in 1972. Since then, most of the cases reported, have been in small series of patients. Most of the reports concern single cases or epidemiological studies. The present study reviews the world literature on MCC. The purpose of this article is to shed light on this unknown neuroendocrine carcinoma and provide the latest information on prognostic markers and treatment options.

Results

The epidemiological studies have revealed that large tumour size, male sex, truncal site, nodal/distant disease at presentation, and duration of disease before presentation, are poor prognostic factors. The recommended initial treatment is extensive local excision. Adjuvant radiation therapy has recently been shown to improve survival. Thus far, no chemotherapy protocol have achieved the same objective.

Conclusion

Although rare, the fatality of this malignancy makes is important to understand the etiology and pathophysiology. During the last few years, the research on MCC has produced prognostic markers, which can be translated into clinical patient care.

Complementary Role of Positron Emission Tomography in Merkel Cell Carcinoma

Merkel cell carcinoma is a rare type of neuroendocrine tumor of the skin with approximately 470 documented new cases annually in the United States. These tumors have high metastatic and recurrence rates, making them aggressive and difficult to treat. Diagnostic workup usually includes computed tomography, magnetic resonance imaging, and scintigraphy methods such as octreotide scans. More recently, positron emission tomographic scanning has been used to evaluate Merkel cell carcinomas. A case of Merkel cell carcinoma, in which positron emission tomography imaging with fluorodeoxyglucose played an important role in staging, re-staging, and identifying previously unknown distant metastatic disease, is presented in this article.

High-risk Merkel cell carcinoma of the skin treated with synchronous carboplatin/etoposide and radiation: a Trans-Tasman Radiation Oncology Group Study--TROG 96:07

PURPOSE

The effectiveness of synchronous carboplatin, etoposide, and radiation therapy was prospectively assessed in a group of patients with high-risk Merkel cell carcinoma (MCC) of the skin.

PATIENTS AND METHODS

Patients were eligible if they had disease localized to the primary site and nodes, and were required to have at least one of the following high risk features: recurrence after initial therapy, involved nodes, primary tumor size greater than 1 cm, gross residual disease after surgery, or occult primary with nodes. Radiation was delivered to the primary site and nodes to a dose of 50 Gy in 25 fractions over 5 weeks and synchronous carboplatin (area under the curve, 4.5) and intravenous etoposide 80 mg/m2 days 1 to 3 was given in weeks 1, 4, 7, and 10. The median age of the group was 67 (range, 43-86) years, and there were 39 males and 14 females. Involved nodes (stage II) were present in 33 cases (62%). The sites involved were head and neck (22 patients), occult primary (13 patients), upper limb (eight patients), lower limb (eight patients), and trunk (two patients).

RESULTS

Fifty-three patients were entered between 1996 and 2001. The median potential follow-up was 48 months. There were no treatment related deaths. The 3-year overall survival, locoregional control, and distant control were 76%, 75%, and 76%, respectively. Tumor site and the presence of nodes were factors that were predictive for local control and survival. Multivariate analysis indicated that the major factor influencing survival was the presence of nodes; however, this was not a significant factor in locoregional control.

CONCLUSION

High levels of locoregional control and survival have been achieved with the addition of chemotherapy to radiation treatment for high-risk MCC of the skin. The role of chemoradiotherapy for high-risk MCC warrants further investigation.

Merkel cell carcinoma--a retrospective analysis of 17 cases

OBJECTIVE

To report clinical experience with the rare neuroendocrine Merkel cell carcinoma of the skin.

SUBJECTS AND SETTING

Seventeen patients with Merkel cell carcinoma of the skin treated at the Departments of Dermatology and ENT, Krankenhaus Dresden-Friedrichstadt, Dresden, Germany, during the years 1984-2000 were evaluated.

METHODS

A retrospective analysis was performed. Age and sex distribution, clinical data and therapy were collected. Outcome measures including overall survival, tumour-free survival and relapse-free survival were determined.

RESULTS

Six male and 11 female patients with an age range of 68-90 years (mean age 73.3 years) were identified. The primary tumour localization was head and neck region (n = 8), upper limbs (8), lower limbs (1). Twelve patients presented in tumour stage I, three in stage II and one in stage III. First line therapy was complete surgical excision with wide margins in 16 patients followed by loco-regional radiation in 12 of 16 cases. In 16 patients follow up data were available. After primary treatment complete response was achieved in 14 of 16 patients (87.5%), two patients had a partial response. The median of relapse-free survival was 44 weeks [mean +/- standard deviation: (44 +/- 118) weeks]. The median of overall survival was 102 weeks [mean +/- standard deviation: (137 +/- 94) weeks]. Three patients with a PR after primary treatment had a median overall survival of only 48 weeks [mean +/- standard deviation: (51 +/- 20) weeks].

CONCLUSIONS

Primary surgical treatment with wide excision combined with radiotherapy seems to be a reasonable first-line treatment but prospective controlled multicentre trials are necessary for validation.

Expression and prognostic significance of matrix metalloproteinases and their tissue inhibitors in primary neuroendocrine carcinoma of the skin

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) have been implicated in the development and progression of many tumors, but data for primary neuroendocrine carcinoma (PNC) of the skin are lacking. The aim of the study was to assess the expression of MMPs and TIMPs in PNC and to evaluate their prognostic significance. Expression of MMP-1, MMP-2, MMP-3, MMP-9, MMP-11, MMP-13, and MMP-14 and TIMP-1, TIMP-2, and TIMP-3 was evaluated by immunohistochemistry on 23 samples of PNC of the skin. The results were matched with clinical features and patient survival. In the 23 specimens of PNC, high (>20% of positive neoplastic cells) MMP-1 expression was found in 13 (56.5%) cases. MMP-2 was evidenced in 12 (52.1%) cases, 8 (34.7%) of which showed high expression in neoplastic cells. MMP-3 was detected in 11 cases (47.8%), with high expression in 9 (39.1%) of them. High MMP-9 expression was observed in 3 (13%) cases, whereas high MMP-14 expression was detected in 11 (47.8%) specimens. Expression of TIMP-1 by neoplastic cells was found in 8 (34.7%) cases, with high expression in 3 cases, whereas high TIMP-3 expression was detected in 21 (91.3%) cases. No immunoreactivity for MMP-11, MMP-13, or TIMP-2 was found. Statistical analysis failed to identify a significant correlation between MMP/TIMP expression and clinical parameters. By univariate analysis, stage >I (P = 0.01), high expression of MMP-1 (P = 0.04) and MMP-3 (P = 0.01) resulted significant negative prognostic factors, whereas by multivariate analysis, stage was the only factor that affected survival (P = 0.02). Our results suggest that MMP-1 and MMP-3 may influence the invasive and metastatic potential of PNCs. It is conceivable that future attempts to specifically block MMP-1 and MMP-3 activity may provide a novel means to inhibit invasiveness and distant spread in selected patients with PNC.

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.

Analysis of toxicity of Merkel cell carcinoma of the skin treated with synchronous carboplatin/etoposide and radiation: a Trans-Tasman Radiation Oncology Group study

PURPOSE

The acute and late toxicities of synchronous carboplatin, etoposide, and radiation therapy were prospectively assessed in a group of patients with high-risk Merkel cell carcinoma of the skin.

PATIENTS AND METHODS

Forty patients from six different centers throughout Australia were entered into a Phase II study under the auspices of the Trans-Tasman Radiation Oncology Group. The trial was activated in 1996 and continues to accrue. Patients are eligible if they have disease localized to the primary site and nodes and are required to have at least one of the following high-risk features: recurrence after initial therapy, involved nodes, primary size greater than 1 cm, gross residual disease after surgery, or occult primary with nodes. Radiation was delivered to the primary site and nodes to a dose of 50 Gy in 25 fractions over 5 weeks, and synchronous carboplatin (area under curve [AUC] 4.5) and etoposide (80 mg/M(2) i.v.) were given on days 1-3 during weeks 1, 4, 7, and 10. The median age of the group was 67 years (43-78).

RESULTS

The median duration of follow-up was 22 months (2-45). There were no treatment-related deaths. Grade 3 or 4 skin toxicity occurred in 63% of patients (95% CI 48, 78). The most serious acute effect was on neutrophils with Grade 3 or 4 (neutrophils < 1 x 10(9)/L), occurring in 60% (95% CI 45, 75) of cases. Complications from neutropenia (fever and sepsis) occurred in 16 patients (40% of cases). The median time for neutropenic complications was 27 days (9-35), and 10/16 (62%) cases of neutropenic fever occurred after the second cycle of chemotherapy. The probability of Grade 3 or 4 late effects on platelets (<50 x 10(9)/L) and hemoglobin (<8 g/dl) was 10% (95% CI 1, 20) and 6% (95% CI 2, 15), respectively. Of the 40 patients, 35 were able to complete 4 cycles of chemotherapy. There were no factors predictive for neutropenic toxicity at a p value < 0.05.

CONCLUSIONS

The protocol has acceptable toxicity, and the treatment has been deliverable in a multi-institutional trial setting. Neutropenia is likely to occur with synchronous carboplatin/etoposide and radiation in this population of patients. The risk of a febrile neutropenia was greatest at the time of the second cycle of chemotherapy, when there was moist desquamation of skin or mucosal membranes that provided a portal for infection. This should be considered in the design of subsequent protocols with chemoradiotherapy.

Clinicopathologic and electron microscopic study of cutaneous neuroendocrine (Merkel cell) carcinoma in a cat with comparisons to human and canine tumors

Malignant neuroendocrine carcinoma of the skin (Merkel cell tumor) was diagnosed in an 18-year-old spayed female Maine Coon Cat. The diagnosis was made on the basis of morphologic and electron microscopic findings. The cat was euthanatized 321 days after surgical excision of the tumor. The tumor's malignancy contrasted with the benign nature of Merkel cell tumors reported in dogs and was consistent with the malignancy of Merkel cell tumors reported in humans.

Merkel cell carcinoma: report of 10 cases and review of the literature

BACKGROUND

Merkel cell carcinoma (MCC) is a rare primary neuroendocrine skin tumor that usually arises in the head and neck or the extremities of elderly patients. Because of the limitation of retrospective data, optimal treatment is not well defined.

OBJECTIVE

Our purpose was to present the clinical course and treatment of 10 patients with MCC and review the published literature on MCC.

METHOD

We conducted a retrospective analysis and obtained detailed clinical information for all 10 patients treated for MCC at our institution from 1986 through 1998. The medical literature was also reviewed for natural history and treatment recommendations using MEDLINE search.

RESULTS

Five men and 5 women received their treatment between 1986 and 1998 for MCC (5 had stage IA disease, 4 stage IB, 1 stage II). The mean age was 70.3 years (range, 47-86 years). Seven tumors were located on the head and neck and 3 on extremities. Five of 10 patients had a relapse (mean time before recurrence, 5.7 months) (range, 2 weeks-20 months); one patient had local recurrence, one had regional lymph node recurrence, and 3 had both local and regional lymph node recurrence. In 4 patients systemic metastases developed. Long survival is also noted (6 to > 164 months); 4 patients died of MCC. After initial surgery, 9 patients received radiotherapy at some point and 3 patients also received chemotherapy. Five of 10 patients had 13 previously treated or coexisting malignant neoplasms. In one patient MCC developed in a previously irradiated field. Review of 875 cases showed a male/female ratio of 1.5:1; location of tumors was as follows: head and neck, 47%; extremities, 40%; trunk, 8%; unknown primary site, 5%. Local recurrence was observed in 25%, regional lymph node involvement in 52%, distant metastasis in 34%, and MCC was a cause of death in 34%.

CONCLUSION

MCC has a high incidence of locoregional recurrence with distant metastases that is more common with higher stage lesions. Early local management of smaller lesions results in good long-term survival. It is not known whether prophylactic lymph node dissection and/or radiation and adjuvant radiation increases survival. Long survival can be achieved after treating locoregional recurrence. The role of chemotherapy is still controversial and should be considered in patients with advanced disease and those not thought to be candidates for surgery.

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.

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.

Neuroendocrine carcinoma of the skin with lymphoepithelioma-like features

We report a case of primary neuroendocrine carcinoma of the skin (PNECS) mimicking a lymphoepithelioma-like carcinoma of the skin (LELCS) with respect to both cytomorphology and the presence of a dense lymphoplasmacytic stroma. The tumor occurred in the left forearm of a 86-year-old woman, and its history was marked by aggressive behavior, with metastases to lymph nodes and to visceral sites within 1.5 years of diagnosis. The neoplastic epithelial cells had an immunophenotypic profile typical of PNECS, reacting for cytokeratin 20 and other low-molecular weight cytokeratins, neuron-specific enolase, neurofilament protein, synaptophysin, and chromogranin A. In addition, they were immunoreactive for epithelial membrane antigen, carcinoembryonic antigen, and S-100 protein, as observed in LELCS of supposed adnexal differentiation. The tumor-infiltrating lymphocytes were mostly of T-lineage, with a predominance of CD8+ cells. We believe the case is a morphologic variant of PNECS, retaining its aggressive behavior and high metastatic potential, and should not be confused with true LELCS, which has a more favorable outcome. Immunohistochemistry is paramount in establishing the diagnosis. Lymphoid infiltration, even if prominent, does not seem to be of favorable prognostic significance in such a context.