Cytological evaluation of head and neck tumors in children--a pattern analysis

A total of 135 pediatric head and neck tumors diagnosed in our institute were reviewed with a view to elucidate the overall cytological patterns and analyze the important cytological features. Ninety-four tumors (69.6%) were aspirated for a primary diagnosis, and in 41 (30.4%) cases, fine-needle aspiration cytology was performed to document relapse, recurrence or a metastasis. Among the 94 tumors aspirated for a primary diagnosis, 66 cases (70.2%) were accurately diagnosed, in 22 cases (23.4%) a broad working diagnosis was offered, and 6 cases (6.4%) were misdiagnosed. The accuracy rate was higher (79.3%) when relapse-recurrent and metastatic tumors were included. The smears were broadly divided into six patterns, viz. round cell, epithelial, anaplastic, giant cell, mixed inflammatory, and spindle cell patterns. The round cell pattern was the most frequent one encountered in this group. The cytological features that stood the test of variability were lymphoglandular bodies and a noncohesive cell population in hematolymphoid malignancies, pale chromatin and cytoplasmic vacuoles in primitive neuroectodermal tumor/Ewing's sarcoma (PNET/ES), neuropil and rosettes in neuroblastoma, and plasmacytoid rhabdomyoblasts in rhabdomyosarcoma. A fairly good accuracy was seen in the diagnosis of metastatic undifferentiated carcinoma and anaplastic lymphoma, but the giant-cell and spindle-cell tumors continued to pose a problem in diagnosis. Ancillary techniques such as immunocytochemistry and electron microscopy applied in limited cases helped evaluate Langerhans cell histiocytosis, alveolar rhabdomyosarcoma, and the PNET/ES family of tumors.