Anemone cell tumor with neuroendocrine differentiation (presumed Merkel cell carcinoma)

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.

Diagnosis of an anemone cell tumor as a B-cell lymphoma by molecular analysis

An 83-year-old man presented with mediastinal and axillary lymphadenopathy. Immunophenotyping and electron microscopy performed on an excision biopsy were inconclusive. On a repeat biopsy a year later the ultrastructural features typical of an anemone cell tumor were seen. A panel of monoclonal antibodies showed positivity for vimentin only. The diagnosis of a high-grade B-cell lymphoma could be made only after detection of immunoglobulin gene rearrangement by polymerase chain reaction gene amplification.

Pleural mesothelioma presenting as an axillary lymph node metastasis with anemone cell appearance

A case of epithelial mesothelioma presenting as an axillary metastasis of unknown origin with anemone cells in a 33-year-old patient with pleural effusion is reported. The differential diagnosis included tumors that can be composed of cells with anemone shape (malignant lymphoma, leukemia, malignant melanoma, carcinoma, and mesothelioma). Tumor cells in the present case were positive for cytokeratins (Cam 5.2 and AE1/3) as well as vimentin antibodies and were consistently negative for carcinoembryonic antigen, Leu-M1, leukocyte common antigen, pan-B-cell and pan-T-cell antigen, Ber-H2, S-100 protein, HMB-45, and epithelial membrane antigen antibodies. On electron microscopy, the most remarkable features were the presence of abundant, long, slender microvilli, the lack of well-developed intercellular junctions, and only occasional tight junctions in some of the tumor cells. A pleural needle biopsy confirmed the pleural origin of the proliferation. The patient refused treatment and died 3 years after diagnosis.

Anaplastic large cell Ki-1 lymphoma of the stomach with villopodial projections: an immunocytochemical and ultrastructural study and review of the literature

The report describes a case of anaplastic large cell Ki-1 lymphoma of the stomach with a rapidly fatal course observed in a 28-year-old woman. By electron microscopy the neoplastic cells presented long projections of the cytoplasmic membrane arranged uniformly along all the cell circumference. The morphology and distribution of these projections were characteristic, and the term villopodial is proposed for them. A review of the literature revealed 18 cases of lymphoma and 7 cases of nonlymphoid neoplasms composed of cells with projections similar to those observed in the present case. It is suggested that such tumors be denominated villopodial lymphomas and villopodial tumors. The present case is the first anaplastic large cell Ki-1 lymphoma with villopodial projections reported in the literature.