Merkel Cell Carcinoma of the Eyelid

PURPOSE

To evaluate the clinical and histopathologic characteristics of Merkel cell carcinoma (MCC) of the eyelid.

DESIGN

Retrospective case series and literature review.

PARTICIPANTS

Three consecutive patients with MCC of the eyelid who were referred to the Ocular Oncology Unit of Leiden University Medical Center, Netherlands.

METHODS

Clinical records and histopathologic material of patients with eyelid MCC were reviewed. The clinical presentation and treatment were evaluated.

MAIN OUTCOME MEASURES

Clinical and histopathologic description of eyelid MCC, with histologic proof of spontaneous regression of the tumor.

RESULTS

Three patients with MCC of the eyelid were included. Diagnosis was made by pathologic investigation and immunohistochemistry (S100, cytokeratin 20, epithelial membrane antigen, chromogranin). Two of the patients showed histologically proven complete spontaneous regression after nonradical excision of the tumor. After local excision, none of the MCCs demonstrated local recurrence, without regional or distant metastases. Mean clinical follow-up was 50 months.

CONCLUSIONS

Nonocular MCC is known to recur in 66% of patients and to be lethal in almost 33%. Merkel cell carcinoma of the eyelid is a rare malignancy that can not be recognized clinically. Clinical differential diagnosis must be made with a chalazion, and histopathologic differential diagnosis must be made with small cell carcinomas. Close follow-up of these patients is advised because of the potential high recurrence rate and lymphatic spread. The immunologic phenomenon of spontaneous regression points out the importance of the immune system in this disease.

What lies beneath? Assessment of leg ulcers during acute hospital admission

Chronic leg ulceration is a common condition often noted in patients during an acute hospital admission. We present the case of a patient in whom thorough examination and investigation of an incidentally noted ulcer revealed a serious, previously unexpected diagnosis of disseminated Merkel cell carcinoma. This article illustrates how important it is that medical staff are aware of the different patterns of an ulcer disease and are alert to atypical appearances. Acute admission, regardless of cause, represents an opportunity for full examination of all ulcers with a view to further investigation or specialist referral if needed. Such assessment can support the often overburdened community services and ensure appropriate investigation and treatment, particularly in the context of detecting malignancy.

TdT expression in Merkel cell carcinoma: potential diagnostic pitfall with blastic hematological malignancies and expanded immunohistochemical analysis

Merkel cell carcinoma is an uncommon aggressive primary cutaneous neuroendocrine carcinoma. Histologically, the differential diagnosis includes the 'small round cell' tumor group, particularly metastatic small cell carcinoma and blastic hematological malignancies involving skin/soft tissues. Terminal deoxynucleotidyl transferase (TdT) is a DNA polymerase, which is a sensitive and specific antibody for acute lymphoblastic lymphoma with a small proportion of acute myeloid leukemia showing positivity. This study investigates the expression of TdT in 20 cases with initial diagnosis of Merkel cell carcinoma. Archival blocks and slides were retrieved and reviewed and clinical information obtained from patient charts. Immunohistochemistry was performed and graded as: 0, no staining; 1+, less than 50% staining in the cells; 2+, 50% or more staining in the cells. After review, 15 cases were confirmed as Merkel cell carcinoma. Immunohistochemical positivity was as follows: 8/15 cases were positive for TdT with strong nuclear staining, morphologically resembling 'blasts', AE1AE3, CAM5.2 (15/15) (both membrane and paranuclear dot positivity), CD56 and BCL-2 (15/15), Synaptophysin (13/15), Chromogranin A (11/15), NSE (15/15), CK20 (14/15), CK7 (3/15), both CK7 and CK20 (3/15), CD117 (8/15), CD99 (2/15), CD10 (1/15). One case was negative for CK7/CK20. All 15 cases were negative for thyroid transcription factor-1, LCA, CD20, CD3 and CD34. Expanded immunohistochemical panel with positive staining for epithelial/neuroendocrine markers, CK20, negative staining for hematolymphoid markers and awareness of TdT expression and other markers that show overlap with blastic hematological malignancies avoids misinterpretation in the diagnosis of Merkel cell carcinoma. This aids in further diagnosis of Merkel cell carcinoma, avoiding the potential diagnostic pitfall with other small round cell tumors and hematological malignancies primary or metastatic to the skin.

[Merkel cell carcinoma of the upper lid]

AIMS

Merkel cell carcinoma (MCC) of the skin is a rare form of cutaneous malignancy of neuroendocrine origin with a propensity to form cutaneous and lymphogenous metastases. The tumor, affecting predominately elderly patients, has a significantly higher incidence in female patients (80%) compared to male patients (20%). The mainstay of therapy is surgical resection with possible adjuvant radio- or chemotherapy.

CASE REPORT

A case of a 78-year-old patient with a MCC of the upper lid without lymph node involvement or distant metastasis is described. The tumor was resected and the defect closed by a temporal skin flap performing a temporary cantholysis. The clinical follow-up revealed an undisturbed eye lid function without any clinical or radiological signs of a locoregional or distant recurrence.

[Merkel cell carcinoma: a report of two cases]

We present two cases of Merkel cell carcinoma (also called cutaneous neuroendocrine carcinoma) and review the relevant literature. This is a rare skin tumor that is very aggressive, with a great tendency to local recurrence and rapid metastatic spread to regional lymph nodes as well as hematogeneous dissemination. We discuss the usefulness of different imaging modalities in determining the extension of disease and in patient follow-up.

Clinical features and management of Merkel cell carcinoma

Merkel cell carcinoma (MCC) is an aggressive dermal tumour of neuroendocrine origin. MCC is a rare tumour and all information pertaining to its behaviour, therapy and prognosis is based on retrospective reports. The two potentially curative treatment modalities are surgery and radiotherapy. It is a rare, highly malignant primary skin tumour, originally called "trabecular carcinoma" of the skin. MCC poses a challenge to the clinician because of its rarity and poor prognosis. The optimal therapy is customised and tailored for each individual patient with the appropriate use of operative resection and radiation therapy. This review covers reports from several authors regarding the rationale of using postoperative radiotherapy to the primary tumour and regional lymphatics. Although MCC is classified as a type of neuroendocrine carcinoma, it is less likely to be controlled by systemic chemotherapy. Management of primary lesion with clinically localised disease is wide excision with margin of at least 2 cm whenever possible. MCC is a radiosensitive tumour, adjuvant radiotherapy has been advocated in order to control local as well as regional disease. Radiation induced toxicity should be considered and discussed with the patient. Adjuvant radiation to the nodal bed after complete lymphadenectomy in patients with metastatic disease is generally not recommended.

Soft Tissue Tumors of the Hand. 2. Malignant

Soft tissue tumors of the hand arise from skin, subcutaneous tissue, tendons, nerve, and blood vessels. Many of these lesions occur on other parts of the body; however, the hand remains a unique site because these tumors have symptoms, appearances, treatments, and prognoses that may be quite different than when on other parts of the body. Their characteristics and the severity of symptoms vary markedly depending on the exact location, size, and type of tumor-and many of these tumors can have multiple forms of presentation. Two articles are intended to provide an overview of benign (previous article) and malignant tumors (this article) of the hand. The rarer and more deleterious tumors are discussed in detail while the common tumors and epidermal lesions with which practitioners are familiar are briefly overviewed. At the completion of these review articles, participants should be able to identify and diagnose various benign and malignant hand tumors as well as understand the accepted current treatment of these growths.

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 masquerading as a chalazion

CASE REPORT

A 62-year-old woman presented with a large rapidly growing violaceous mass initially diagnosed as a chalazion. Histopathologic examination disclosed Merkel cell carcinoma (MCC). Radiotherapy was not tolerated. Despite chemotherapy, she succumbed to widespread metastases 13 months later.

COMMENTS

MCC must be included in the differential diagnosis of solitary eyelid nodules, requiring early and aggressive treatment.

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

Merkel cell carcinomas are rare neuroendocrine tumors of the skin with highly malignant behavior. These tumors arise from Merkel cells, which are slowly adapting type 1 mechanoreceptors that occur in hair follicles and the basal layer of the epidermis. Merkel cell carcinomas are typically located in the dermis and frequently extend into the subcutaneous fat and lymphatics. This case report describes the magnetic resonance imaging and pathologic findings, surgical treatment, and postoperative results with review of the literature for Merkel cell carcinoma involving the foot of a 72-year-old man with a 2-month history of a painless, enlarging mass that interfered with his ability to wear a shoe.

Merkel Cell Tumor in a Trichilemmal Cyst: Collision or Association?

An 86-year-old white male presented with an erythematous, painless, slowly growing, and firm left thigh nodule. Histologic examination revealed a dermal proliferation of monomorphous cells arranged in trabeculae, nests, and sheets with an infiltrative growth pattern. The cells had a high nuclear-cytoplasmic ratio, finely granular nuclear chromatin, and nuclear molding. Numerous mitotic figures, apoptotic cells, and individual cell necrosis were present; lymphovascular invasion was identified. The tumor was attached, demonstrating pagetoid intraepithelial migration, to a follicular cyst lined by squamous epithelium, lacking a granular cell layer and filled with compact keratinous content, diagnostic of trichilemmal cyst. Immunohistochemical study revealed that tumor cells expressed pan-cytokeratin (CK), chromogranin, synaptophysin, neuron-specific enolase, and CK20 (dotlike staining pattern), thus supporting the diagnosis of Merkel cell carcinoma. The association of Merkel cell carcinoma with a cyst is an exceptionally rare occurrence. As a result of the prominent involvement of the cyst wall by tumor cells, we favor that in this case carcinoma arose in the trichilemmal cyst rather than being a collision tumor. This hypothesis is also supported by the recent observation that Merkel cells are frequently present within normal hair follicles, especially in the isthmic portion that corresponds with the area of origin of the trichilemmal cyst.

Merkel cell carcinoma: clinicopathological aspects of an unusual neoplasm

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous cancer that predominately affects elderly Caucasians with fair skin and has a propensity for local recurrence and regional lymph node metastases. It can occur on the face, the trunk, the genitalia, and the perianal region. The median age of the patients is 69 years, but it may occur earlier and more frequently in immunosuppressed patients. MCC usually arises in the dermis and extends into the subcutis. It may be difficult to accurately diagnose MCC by light microscopy alone and ancillary techniques, including electron microscopy and immunohistochemistry, may be necessary for a definitive diagnosis. The management of MCC is dependent on the stage of the disease and is hampered by its rarity and lack of randomized trials. Nonetheless, for localized disease most guidelines include wide local excision of the primary tumor either alone or followed by radiation therapy. Sentinel lymph node biopsy can be helpful in staging and prognosis, but its benefit in survival remains to be seen. Systemic chemotherapy may be considered as an adjuvant following surgery or to treat locoregional or distant disease. The prognosis of MCC is variable. In patients with localized disease the course is indolent and is well-controlled with local excision alone. On the other hand, many tumors are aggressive and have a tendency for locoregional recurrence and distant metastases. Such patients have a grim prognosis, with a median survival of 9 months. Successful outcome most often is seen in patients with early diagnosis and complete excision.

Merkel cell carcinoma: a case report

Merkel cell carcinoma is an uncommon, highly malignant, primary cutaneous neuroendocrine tumour mostly occurring as a solitary nodule on the head or on the extremities. It has high recurrence rate. We hereby report a case of Merkel cell carcinoma in a young woman.

Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous cancer that predominately affects elderly Caucasians with fair skin and has a propensity for local recurrence and regional lymph node metastases. A variety of terms have been used to describe this tumor, including trabecular cell carcinoma, neuroendocrine or primary small cell carcinoma of the skin, and anaplastic cancer of the skin. Although the skin lesion is most commonly found on sun-exposed areas of the head and neck or extremities, it can occur on the trunk, genitalia, and perianal region. The median age is 69 years, but it may occur earlier and more frequently in immunosuppressed patients. Patients with MCC frequently present with a nonspecific erythematous or violaceous firm nodule or small plaque that may be surrounded by small satellite tumors. MCC usually arises in the dermis and extends into the subcutis. It may be difficult to accurately diagnose MCC by light microscopy alone and ancillary techniques, including electron microscopy and immunohistochemistry, may be necessary to make a definitive diagnosis. Management of MCC is dependent on stage of the disease and is hampered by its rarity and lack of randomized trials. Nonetheless, for localized disease most guidelines include wide local excision of the primary tumor either alone or with radiation therapy. Sentinel lymph node biopsy can be helpful in staging and prognosis, but its benefit in survival remains to be seen. Systemic chemotherapy, akin to regimens for small cell carcinoma of the lung, may be considered as an adjuvant following surgery or to treat locoregional or distant disease. The prognosis of MCC is variable. Some patients with localized disease have an indolent course and are well controlled with local excision alone. On the other hand, many tumors are aggressive and have a tendency for locoregional recurrence and distant metastases. Such patients have a grim prognosis with a median survival of 9 months. Successful outcomes are most often seen in patients with early diagnosis and complete excision.

Merkel cell carcinoma and multiple primary cancers

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine tumor of the skin for which causative factors remain largely unknown. The site-specific risks of multiple primary cancers associated with MCC, which may provide insight into etiologic influences, have not been quantified in large population-based studies. We estimated the long-term risk of subsequent primary tumors after a first primary MCC (1,306 patients) and the risk of second primary MCC following other first primary cancers (2,048,739 patients) within 11 population-based cancer registries which report to the National Cancer Institute's Surveillance, Epidemiology, and End Results Program (1986-2002). Patients with first primary MCC were at significantly increased risk of developing a subsequent cancer [standardized incidence ratio (SIR), 1.22; 95% confidence intervals (95% CI), 1.01-1.45; observed (O = 122)], with significant excesses restricted to the first year after diagnosis (SIR, 1.71; 95% CI, 1.21-2.33; O = 39). Significantly elevated site-specific risks were observed for cancers of salivary gland (SIR, 11.55; 95% CI, 2.32-33.76; O = 3), biliary sites other than liver and gallbladder (SIR, 7.24; 95% CI, 1.46-21.16; O = 3), and non-Hodgkin lymphoma (SIR, 2.56; 95% CI, 1.23-4.71; O = 10). Nonsignificantly increased risks of 2-fold or higher were seen for chronic lymphocytic leukemia, and cancers of the small intestine and brain. A significantly increased 1.36-fold risk (95% CI, 1.19-1.55; O = 221) of MCC as a second primary malignancy was observed among patients with all other first primary cancers taken together. In particular, significant 3- to 7-fold excesses of MCC followed multiple myeloma (SIR, 3.70; 95% CI, 1.01-9.47; O = 4), chronic lymphocytic leukemia (SIR, 6.89; 95% CI, 3.77-11.57; O = 14), non-Hodgkin lymphoma (SIR, 3.37; 95% CI, 1.93-5.47; O = 16), and malignant melanoma (SIR, 3.05; 95% CI, 1.74-4.95; O = 16). Although enhanced medical surveillance may play a role, increased reciprocal risks suggest that MCC may share etiologic influences with other malignancies. Heightened awareness of the associations of lymphohematopoietic malignancies with MCC may facilitate early clinical recognition.

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]

Merkel cell carcinoma is a rare form of skin cancer of likely neuroendocrine origin wich affects mainly white population in sun-exposed areas. It is an aggressive tumor and survival is dependent on stage at the time of diagnosis. The staging evaluation include CT imaging and recently PET scan. Surgical excision with or without lymph node dissection, followed by postoperative radiotherapy in stage II disease, is the standard treatment of non metastatic disease. The role of adjuvant chemotherapy is still controversial. In patients with metastatic disease, chemotherapy regimens active in small cell lung cancer are generally used. The combination of cyclophosphamide, doxorubicin and vincristine (CAV) has an overall response rate of 75%, whereas the response rate of etoposide in combination with cisplatin or carboplatin is 60%. Experience with other therapeutic agents, such as tumor necrosis factor, interferon and octreotide is scanty. Recently, encouraging preliminary results with targeted agents have been reported. Our experience in 14 patients, four of whom treated with chemotherapy for advanced disease, is in agreement with literature

Non-Hodgkin lymphoma and skin cancer: A dangerous combination

There is a significant association between non-Hodgkin lymphoma, including chronic lymphocytic leukaemia, and both melanoma and non-melanoma skin cancer. This review highlights the existing data on the phenomenon of accelerated skin cancer in patients with non-Hodgkin lymphoma and specifically chronic lymphocytic leukaemia. The outcomes of patients with non-Hodgkin lymphoma (including chronic lymphocytic leukaemia) and non-melanoma skin cancer are worse than in patients without concomitant lymphoreticular malignancy, as shown by increased rates of local recurrence, regional metastasis and death. Pathogenic factors may be common between non-Hodgkin lymphoma and chronic lymphocytic leukaemia and skin cancer. The treatment of skin cancer in patients with non-Hodgkin lymphoma must factor in the worse prognosis and adapt standard therapeutic approaches to minimize the risk of metastasis and death. Preventive strategies and early detection are paramount in this high-risk population.

Merkel cell tumour of the external ear. Report of a case

Merkel cells carcinoma (MCC) is an uncommon skin lesion, considered a malignancy of the neuroendocrine system, which is found mainly in elderly people. Its incidence is highly correlated with sun exposure or immunodeficiency syndromes. MCC is often an aggressive tumour with high tendency for local recurrence, lymph node involvement and distant metastasis. To our best knowledge 20 cases originated from the auricle have been described, 2 of them arising from external ear canal. The authors report a case of the ear canal characterized by two others synchronous tumours and the occurrence of a malignant high grade lymphoma, in which contribute of the pathologist was essential for a critical review. MCC diagnosis is not always easy for its pathological and clinical features and it should always be considered in presence of lymphoma. A multidisciplinary approach is basic.

[Merkel cell carcinoma]

Merkel cell carcinoma (Mcc) is a very rare, malignant, neuroendocrine tumour. Mcc has an aggressive behavior, local recurrence, and regional or distant metastasis generally develop within a short period of time. At the Oral Medicine Department 158,056 patients were treated between 1970 and 2004. A single case of Mcc was diagnosed, in a 79-year-old woman. The tumour was localized to the upper lip. After successful cryosurgery and a 7-year tumour-free period, a new tumour developed in her palatine tonsil. It was an anaplastic carcinoma with neuroendocrine features, raising the possibility of a late haematogenous metastasis, a second field tumour, or a second primary tumour. The clinical, histological, immunohistochemical and genetic findings suggested that the tumour of the palatine tonsil is a second field tumour.

Merkel cell carcinoma (primary cutaneous neuroendocrine carcinoma): An overview on management

Merkel cell carcinoma is an uncommon but aggressive primary cutaneous neuroendocrine (small cell) carcinoma. There is ongoing debate regarding the optimal treatment of this disease. The early literature comprised small institutional studies with inherent weaknesses. Recent data have emerged from larger studies, including those from Australian institutions, that adds support to a multimodality approach as best practice. Despite this, the outcome for patients with unfavourable disease remains poor and in most series 25-30% of patients die as a direct result of Merkel cell carcinoma. The head and neck is the commonest site for presentation (50-60%) and wide excision (2-3 cm) of the primary lesion is usually recommended, although achieving this is often difficult within functional and cosmetic constraints. All clinically node-negative patients should be considered candidates for elective nodal treatment and those with clinical nodal disease should undergo nodal dissection and adjuvant radiotherapy. Recent evidence suggests that patients treated with surgery and adjuvant locoregional radiotherapy experience a better disease-free survival compared with those undergoing surgery alone. The role of platinum-based chemotherapy is evolving. The aim of this article is to discuss relevant issues in the management of a patient with Merkel cell carcinoma.

Merkel Cell Carcinoma Guidelines

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous tumor that combines the local recurrence rates of infiltrative non-melanoma skin cancer with the regional and distant metastatic rates of thick melanoma. The mortality rate of MCC exceeds that of melanoma, and the 5-year disease-specific survival rate is 64%. These guidelines and most biomedical literature suggest that the workup of a patient with MCC should include chest radiograph and additional studies as clinically indicated. These guidelines, which the NCCN Non-Melanoma Skin Cancer Panel developed as a supplement to those for squamous cell and basal cell skin cancer, also outline treatment strategies.

For the most recent version of the guidelines, please visit NCCN.org

Pax-5 immunoexpression in various types of benign and malignant tumours: a high-throughput tissue microarray analysis

BACKGROUND

Pax-5 belongs to the Pax gene family transcription factors that play an important role in organogenesis and in B cell ontogeny. It is expressed in B cell non-Hodgkin's lymphoma (B-NHL), Hodgkin's lymphoma (HL) and neuroendocrine carcinomas. However, its expression in other tumour types is not fully explored.

AIMS AND METHODS

To determine Pax-5 expression in other tumour types, immunohistochemistry was performed on 3758 benign and malignant tumours using multiple tumour microarrays, as well as on whole sections.

RESULTS

Pax-5 was expressed in 108/118 (91.5%) B-NHLs, in 60/70 (85.7%) HLs and in 0/7 T cell lymphomas. In addition, Pax-5 was seen in 24/34 (70.6%) Merkel cell carcinomas, 42/53 (79.2%) small cell carcinomas, 1/164 (0.6%) breast carcinomas, 2/204 (1%) endometrial adenocarcinomas and 1/452 (0.2%) urothelial carcinoma of the bladder.

CONCLUSION

Despite its expression in a small subset of malignancies of epithelial origin, Pax-5 is still a good and reliable immunomarker in diagnosing B-NHL, HL and neuroendocrine carcinomas.

Sentinel lymph node biopsy for evaluation and treatment of patients with Merkel cell carcinoma: The Dana-Farber experience and meta-analysis of the literature

OBJECTIVE

To determine the diagnostic accuracy and usefulness of sentinel lymph node biopsy (SLNB) and computed tomographic scans in the initial evaluation and treatment of patients with Merkel cell carcinoma (MCC).

DESIGN

Single-institution case series and literature-based case-level meta-analysis.

SETTING

Academic cutaneous oncology clinic.Patients Sixty-one adults with biopsy-proven MCC (30 who had undergone SLNB) plus 92 cases from the literature of patients who had undergone SLNB.

MAIN OUTCOME MEASURES

Relapse-free survival.

RESULTS

In 122 patients with no nodal disease found by physical examination, SLNB findings revealed nodal involvement in 39 cases (32%). At 3 years, the recurrence rate for those with a positive SLNB was 3 times (60%) higher than for those with a negative SLNB (20%; P = .03). Patients with a positive SLNB who received adjuvant nodal therapy had a relapse-free survival rate of 51% at 3 years (n = 26) compared with 0% for patients who did not receive nodal therapy (n = 3; P < .01). In contrast, among patients with a negative SLNB there was no significant difference in 3-year relapse-free survival rates for those who did (90%; n = 24) or did not (70%; n = 19; P = .26) receive adjuvant nodal therapy. Using SLNB plus clinical follow-up as a gold standard, computed tomographic scans had low sensitivity (20%) for detecting MCC that had spread to the lymph node basin and low specificity for distant disease (only 4 of 21 "positive" scans were confirmed during 6 months of follow-up).

CONCLUSIONS

Sentinel lymph node biopsy detects MCC spread in one third of patients whose tumors would have otherwise been clinically and radiologically understaged and who may not have received treatment to the involved node bed. There was a significant benefit of adjuvant nodal therapy, but only when the SLNB was positive. Thus, SLNB is important for both prognosis and therapy and should be performed routinely for patients with MCC. In contrast, computed tomographic scans have poor sensitivity in detecting nodal disease as well as poor specificity in detecting distant disease.