LAUSR

© BMJ Publishing Group Limited 2022. No commercial reuse. See rights and permissions. Published by BMJ. DESCRIPTION A man in his 50s, a known case of hypopharyngeal squamous cell carcinoma (SCC) which was moderately differentiated (cT4b, N2c, M0: stage IVB), without any local infiltration, diagnosed 1 year ago, who had completed three cycles of chemoradiation therapy, was referred to us in view of reddish nonpruritic skin lesions over the left side of chest, for the past 3 months. There was a history of prolonged use of tobacco for the past 20 years which, in addition to the older age group, was a clinical risk factor for SCC of the hypopharynx. The lesions initially started as small reddish papules that subsequently progressed in size. Examination revealed multiple, welldefined, erythematous, tender, nodules and plaques of sizes ranging from 2×1 cm to 10×8 cm with superficial pale greasy crusts and surrounded by erythematous macules, present over the left side of chest and left upper abdomen (figure 1A,B). A biopsy from the nodule revealed fibrocollagenous tissue bits showing infiltration by nests and sheets of malignant squamous cells exhibiting moderate anisonucleosis, coarse chromatin, inconspicuous nucleoli and moderate cytoplasm, suggestive of metastatic deposits from SCC (figure 1C,D). A final diagnosis of cutaneous metastasis secondary to SCC of the hypopharynx was made, following which the staging of the carcinoma was revised as cT4b, N2c, M1: stage IVC. In our case, there was radiologically proven primary SCC in the hypopharynx. However, apart from the skin metastasis, there were no other internal metastatic foci evidenced by radiological examination. The patient was followed up in medical oncology outpatient department. Head and neck squamous cell carcinoma (HNSCC) metastasises to other body parts in 15%–20% of cases. However, cutaneous metastasis of HNSCC is very rare with an incidence of 0.8%–1.3%. Carcinoma hypopharynx is a small subset of HNSCC, and cutaneous metastasis in this group is extremely rare. Furthermore, they could be the first evidence of undiagnosed internal cancer, a tumour relapse or failure of treatment. Even though the primary tumour was being treated in the current case, the rapid dissemination of the tumour indicates the aggressiveness of cancer. Cutaneous metastases are differentiated from primary skin tumours by their clinical presentations and histological features. Unlike primary skin tumours, cutaneous metastases rapidly grow in the dermis with intact overlying epidermis. In most cases, the metastatic deposits show histological features that resemble the underlying primary malignancy, may be more anaplastic and show less differentiation. In our case, histology showed infiltration of fibrocollagenous tissue by nests and sheets of malignant squamous cells in the dermis, exhibiting moderate anisonucleosis, coarse chromatin and inconspicuous nucleoli, suggestive of metastatic deposits from SCC of the hypopharynx. Cutaneous metastasis in hypopharyngeal carcinoma is extremely rare and few cases have been reported so far. Patients with hypopharyngeal carcinoma who develop skin metastases often have a poor prognosis and a short lifespan. It may indicate Figure 1 (A) Welldefined erythematous nodules and plaques on the left side of chest. (B) Scattered erythematous nodules on the anterior chest and abdomen. (C) Histological examination: infiltration of dermis by nests and sheets of large cells (H&E stain, 10×). (D) Higher magnification view of nuclear atypia (H&E stain, 40×).