Merkel cell carcinoma

Combined Merkel Cell Carcinoma with Nodal Presentation: Report of a Case Diagnosed with Excisional but Not Incisional Biopsy and Literature Review

/ CY Liu / 發表迴響

Chih-Yi Liu 1 2, Nai-Wen Kang 3, Kengo Takeuchi 4 5 6, Shih-Sung Chuang 7

Affiliations
  1. Division of Pathology, Sijhih Cathay General Hospital, New Taipei City 221, Taiwan.
  2. School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei City 221, Taiwan.
  3. Division of Hemato-Oncology, Department of Internal Medicine, Chi-Mei Medical Center, Tainan 710, Taiwan.
  4. Division of Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo 135-8550, Japan.
  5. Pathology Project for Molecular Targets, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo 135-8550, Japan.
  6. Department of Pathology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo 135-8550, Japan.
  7. Department of Pathology, Chi-Mei Medical Center, Tainan 710, Taiwan.

ABSTRACT

Merkel cell carcinoma (MCC) is a rare primary neuroendocrine carcinoma (NEC) of the skin. As compared to pure MCCs, combined MCCs are aggressive and exhibit a higher probability of metastasis. A correct diagnosis might be missed, especially when the biopsy sample is too small or too superficial. We report a 79-year-old Taiwanese male who presented with lymphadenopathy suspicious for lymphoma. A nodal biopsy showed metastatic NEC. A skin tumor in the lower back was identified, and an incisional biopsy showed only squamous cell carcinoma (SCC). A subsequent excisional biopsy was performed based on the advice of the senior pathologist because of the presence of metastatic nodal NEC. Finally, a diagnosis of combined MCC and SCC was confirmed. Our literature review identified 13 cases of combined MCC with nodal metastasis as initial presentations, all with an aggressive clinical course. Both the MCC and non-MCC components could be present in the metastatic nodes. Metastases of pure MCC cells were observed in three combined MCCs in sun-protected areas, probably pointing to a distinct pathogenesis. Excision or punch biopsy to include the deep dermal NEC component is recommended as timely diagnosis is mandatory for appropriate management of patients with this rare skin cancer.

Keywords: Merkel cell carcinoma; Merkel cell polyomavirus; cytology; paranuclear blue inclusion; skin cancer; thyroid transcription factor-1.

>Diagnostics (Basel). 2023 Jan 26;13(3):449. doi: 10.3390/diagnostics13030449.

15. Combined Merkel Cell Carcinoma with Nodal Presentation Report of a Case (參考著作)下載

Diagnostic clues for differentiating Merkel cell carcinoma from lymphoma in fine-needle aspiration cytology

/ CY Liu / 發表迴響

Chih-Yi Liu 1 2, Feng-Jie Lai 3, Sheng-Tsung Chang 4 5, Shih-Sung Chuang 4

Affiliations
  1. Division of Pathology, Sijhih Cathay General Hospital, New Taipei City, Taiwan.
  2. College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
  3. Department of Dermatology, Chi-Mei Medical Center, Tainan, Taiwan.
  4. Department of Pathology, Chi-Mei Medical Center, Tainan, Taiwan.
  5. Department of Nursing, National Tainan Institute of Nursing, Tainan, Taiwan.

ABSTRACT

Nodal fine needle aspiration (FNA) is usually the first procedure in the work-up of malignancy of unknown primary. Merkel cell carcinoma (MCC) is an aggressive cutaneous cancer more common in Caucasians but rare among Asians. It is a diagnostic challenge in evaluating FNA from a metastatic MCC without the knowledge of a current or prior history of skin cancer. We report the case of a Taiwanese male with cervical and axillary masses. The diagnosis of the FNA from the axillary lymph node was lymphoproliferative lesion suspicious for lymphoma. The histopathological evaluation of nodal biopsy revealed a metastatic neuroendocrine carcinoma and the subsequent excision of the right palm tumor confirmed MCC. Retrospective review of the FNA and imprint cytology smears of the nodal biopsy showed nuclear molding, Indian filing and rare cytoplasmic pale bodies, but no lymphoglandular bodies. Cytologically metastatic MCC may mimic small round cell tumor including lymphoma, we consider these three cytological features as additional diagnostic clues for metastatic MCC. In this report, we present the cytologic and pathological features of this metastatic MCC and discuss the differential diagnosis of the cytologic mimickers.

Keywords: Indian filing; Merkel cell carcinoma; cytoplasmic pale body; fine-needle aspiration cytology; nuclear molding.

< Case Reports >Diagn Cytopathol. 2022 Jan;50(1):E23-E27. doi: 10.1002/dc.24872. Epub 2021 Sep 7.

6. Diagnostic clues for differentiating Merkel cell carcinoma from lymphoma (參考著作)下載

Merkel cell carcinoma in Taiwan: a subset is chronic arsenicism-related, and the Merkel cell polyomavirus-negative cases are pathologically distinct from virus-related cases with a poorer outcome

/ CY Liu / 發表迴響

Chih-Yi Liu 1, Yun-Ru Lai 2, Pai-Shan Cheng 3, Wei-Wen Yu 4, Ren Ching Wang 5, Wan-Lin Shen 6, Shih-Sung Chuang 7

Affiliations
  1. Division of Pathology, Sijhih Cathay General Hospital, New Taipei City, Taiwan; School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan; School of Medicine, National Tsing Hua University, Hsinchu City, Taiwan.
  2. Department of Anatomical Pathology, Far Eastern Memorial Hospital, New Taipei City, Taiwan.
  3. Department of Dermatology, Chi Mei Medical Center, Tainan, Taiwan.
  4. Department of Dermatology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
  5. Department of Pathology, China Medical University Hospital, Taichung, Taiwan; Department of Nursing, Hung Kuang University, Taichung, Taiwan.
  6. Department of Pathology, Lio Ying Chi-Mei Hospital, Tainan, Taiwan.
  7. Department of Pathology, Chi-Mei Medical Center, Tainan, Taiwan. Electronic address: cmh5301@mail.chimei.org.tw.

ABSTRACT

Merkel cell carcinoma (MCC) is a rare primary neuroendocrine carcinoma of the skin, more frequent in the West than in the East. The pathogenesis is complex, with Merkel cell polyomavirus (MCPyV) and ultraviolet (UV) light being reported to play important roles. In this retrospective study of MCC cases from Taiwan, we analysed the prognostic significance of pathological features and the status of MCPyV and retinoblastoma (Rb) expression. We retrospectively collected MCC cases from five hospitals in Taiwan from 1994 to 2022. We examined the clinical and pathological features, performed immunohistochemical studies for the large T antigen of MCPyV and Rb, and reviewed medical records from electronic data. Disease-specific survival was estimated by using the Kaplan-Meier estimate and compared between subgroups using log-rank test. The clinical and pathological features and the immunohistochemical profiles between subgroups were compared using the Fisher exact test for categorical variables. The 38 patients were mostly (71%) males, with a median age of 79. In 22 (58%) patients, the tumours occurred in sun-exposed areas. Clinically, five (13%) patients had chronic arsenicism. Histopathologically, 11 (29%) cases showed combined tumours (MCC with squamous cell carcinoma or Bowen disease/squamous carcinoma in situ). Seventeen (45%) cases were positive for MCPyV, whereas all combined tumours were negative. MCPyV-negative MCC displayed distinctive pathological features, including epidermal changes, presence of an intraepidermal MCC component, linear or single-file growth pattern, and pleomorphic nuclei. Immunohistochemically, 59% (22/37) MCC cases showed complete loss of Rb protein expression, more frequent in MCPyV-unrelated (p<0.001) and combined (p=0.014) cases, ​but without statistical significance among patients with chronic arsenicism, sun exposure, or disease-specific survival. MCPyV-negative cases exhibited a shorter disease-specific survival than MCPyV-positive cases (median overall survival 13 months vs not reached; p=0.041). MCPyV-negative or combined MCCs were associated with a higher disease-specific mortality and poorer prognosis. MCCs occurring in sun-shielded sites, MCPyV-negativity, and combined tumours correlated with a higher disease-specific mortality and a poorer prognosis by multivariable Cox proportional hazard model. The occurrence of MCCs with arsenic exposure was also identified. Our study showed that MCPyV-negative MCC cases in Taiwan exhibited distinctive pathological features and a poorer outcome than MCPyV-related cases. We also confirmed an association of chronic arsenicism with MCC, which might be considered as the third pathogenetic factor after MCPyV and UV light. Further studies including epidemiological and genetic investigations are warranted to elucidate the pathogenesis of MCC in Taiwan, particularly the significance of chronic arsenicism.

Keywords: Merkel cell carcinoma; Merkel cell polyomavirus; UV; arsenic; chronic arsenicism; neuroendocrine carcinoma; skin cancer.

>Pathology. 2025 Apr;57(3):311-319. doi: 10.1016/j.pathol.2024.09.019. Epub 2024 Dec 29.

1. Merkel cell carcinoma in Taiwan(2025)下載