(Figure 1)The diagnosis however was not revised and the patient underwent excision of the left neck cystic mass under general anaesthesia. The cyst was easily removed. No tract was found connecting the cyst to pharynx or hyoid bone. Few enlarged cervical lymph nodes at level II and III were excised for histopathology examination. He recovered from the surgery uneventfully. Histological examination of the cystic mass revealed a lymph node with cystic degeneration, showing cohesive sheets of malignant cells in lymphocyte and plasma cells rich stroma (Figure 2). The tumour cells demonstrate large vesicular nuclei and prominent nucleoli. There was no definite squamous or glandular differentiation is seen. Immunohistochemical studies revealed tumour cells were highlighted with cytokeratin stain (AE1/AE3) but negative for CD3, CD20, CD30, CK7, CK20, TTF-1, HMB45 and Ki67. These findings support the diagnosis of metastatic undifferentiated carcinoma with possible primary tumour at head and neck
(Figure 1)The diagnosis however was not revised and the patient underwent excision of the left neck cystic mass under general anaesthesia. The cyst was easily removed. No tract was found connecting the cyst to pharynx or hyoid bone. Few enlarged cervical lymph nodes at level II and III were excised for histopathology examination. He recovered from the surgery uneventfully. Histological examination of the cystic mass revealed a lymph node with cystic degeneration, showing cohesive sheets of malignant cells in lymphocyte and plasma cells rich stroma (Figure 2). The tumour cells demonstrate large vesicular nuclei and prominent nucleoli. There was no definite squamous or glandular differentiation is seen. Immunohistochemical studies revealed tumour cells were highlighted with cytokeratin stain (AE1/AE3) but negative for CD3, CD20, CD30, CK7, CK20, TTF-1, HMB45 and Ki67. These findings support the diagnosis of metastatic undifferentiated carcinoma with possible primary tumour at head and neck