Metastatic Pulmonary Adenocarcinoma Deposit Arising Within a Cutaneous Basal Cell Carcinoma: A Case Report

Abstract

Skin metastases are rare complications of internal malignancies, and most commonly arise from primary lung carcinoma (Brownstein and Helwig in Arch Dermatol 105:82-68, 1972). Metastatic cutaneous lesions have not previously been documented to arise within other skin tumours. We report our experience of a solitary pulmonary adenocarcinoma metastasis that arose within a preexisting basal cell carcinoma in a patient with undiagnosed lung cancer. Immunohistochemistry was invaluable in confirming both the metastatic nature of the secondary skin lesion and its site of origin.Keywords Adenocarcinoma Á Basal cell carcinoma Á Skin Á Metastasis Á Thyroid transcription factor-1 Á Tumour-to-tumour metastasis Case PresentationAn 83-year-old male was referred by his general practitioner (GP) to the maxillofacial department at Morriston Hospital, Swansea, UK complaining of a slow growing, painless skin nodule on the left neck present for several months. The GP also wrote to inform the department that the patient was concurrently being investigated for chest pain and shortness of breath on exertion.On examination, there was a 2 cm fleshy lesion over the left posterior triangle (Fig. 1). There was no associated ulceration, induration, or surrounding erythema, and no cervical lymphadenopathy or other cutaneous lesions were noted. The treatment, from a surgical point of view, was a wide elliptical excision with 5 mm margins, and the specimen was sent for histopathological examination.Hematoxylin and eosin (H&E) stained sections revealed nests and lobules of hyperchromatic, uniform, basaloid cells with peripheral palisading and loose stroma, consistent with basal cell carcinoma (BCC). In between these classic areas of BCC were irregular nests of highly atypical cells characterized by abundant eosinophilic cytoplasm, irregular nuclei, fine chromatin, and one or more prominent nucleoli. Mitotic figures were readily identified. Similar cells were identified in lymph-vascular spaces (Fig. 2). This pleomorphic population had features suggestive of squamous cells. In fact, the lesion was initially reported as a BCC with co-existent squamous cell carcinoma, the latter most likely derived from the former, i.e. a baso-squamous carcinoma. Immunohistochemical staining of the skin tumour confirmed the dimorphic nature of the lesion, with strong EMA positivity in the pleomorphic squamoid dermal and intra-lymphatic deposits. In contrast, the basal cell component was EMA negative.A chest X-ray, performed for his concurrent respiratory symptoms, was highly suggestive of a primary lung cancer with nodal and distant metastases, with a provisional radiologic staging of T4 N3 M1. A CT-guided core needle biopsy was reported as a non-small cell carcinoma of the Electronic supplementary material The online version of this article

Signet‐ring cell gastric adenocarcinoma metastasizing into a primary cutaneous squamous cell carcinoma of the scalp

“…Richardson and Katayama 7 found that the host tumor was a benign neoplasm more frequently than a malignant one. Table 1 8–18 summarizes all previously reported cases of tumor‐to‐tumor metastasis in which a cutaneous or subcutaneous neoplasm served as the recipient. Although the case reported by Kabukcuoglu et al 14 was a breast carcinoma metastasizing into a subcutaneous myxoid liposarcoma, the images presented are insufficient to confirm that the case is fully credible.…”

“…In our analysis, we have only found four previously reported cases with a malignant cutaneous or subcutaneous tumor functioning as the recipient. One case was a melanoma that metastasized into a basal cell carcinoma, 11 one showed metastatic breast carcinoma within myxoid liposarcoma, 14 one showed metastatic pulmonary adenocarcinoma within basal cell carcinoma 17 and one showed gastric signet‐ring carcinoma secondarily involving basal cell carcinoma 18 …”

Signet‐ring cell gastric adenocarcinoma metastasizing into a primary cutaneous squamous cell carcinoma of the scalp

“…In our analysis, we have only found four previously reported cases with a malignant cutaneous or subcutaneous tumor functioning as the recipient. One case was a melanoma that metastasized into a basal cell carcinoma, 11 one showed metastatic breast carcinoma within myxoid liposarcoma, 14 one showed metastatic pulmonary adenocarcinoma within basal cell carcinoma 17 and one showed gastric signet-ring carcinoma secondarily involving basal cell carcinoma. 18 Gastric adenocarcinoma represents the most common malignancy to assume signet-ring morphology, although virtually any adenocarcinoma may show foci of signet-ring cell change.…”