Clinicopathological Profile of Sinonasal Tumors – A Five Year Study.

The nasal cavity and paranasal sinuses including the maxillary, ethmoid, sphenoid and frontal sinuses are collectively referred to as the sinonasal tract. The sinonasal tract is anatomically and embryologically distinct from the nasopharynx. Although the sinonasal tract and nasopharynx have identical appearing ciliated respiratory epithelium, the epithelium of the sinonasal tract is ectodermally derived, while that of nasopharynx is endodermally derived. This embryologic difference may be a factor in the development of certain epithelial lesions unique to these surfaces eg.schneiderian papillomas of sinonasal tract and nasopharyngeal carcinomas.7 The mucosa of the nasal cavity and paranasal sinuses is often referred to as schneiderian mucosa to emphasize its ectodermal origin as opposed to the endodermal origin of the morphologically identical mucosa lining the rest of the respiratory tract. Nasal stroma is well vascularised fibromuscular tissue. This is occasionally misinterpreted as a vascular malformation or a vascular tumour. In the paranasal sinuses a layer of thin cancellous bone supports this mucosal and stromal arrangement.8 Tumors of the nasal cavity and paranasal sinuses are rare pathologies with extremely varied etiopathology,clinical behaviour,treatment and prognosis. The symptoms of the neoplastic processes are essentially similar to inflammatory pathology of the sinonasal tract with resultant delay of diagnosis. The clinical and radiological features of masses of nasal cavity and paranasal sinuses are overlapping and often only a provisional diagnosis is possible. Definite diagnosis requires histopathological examination as most of the lesions are inaccessible for fine needle aspiration or FNAC is not recommended because of fear of haemorrhage. In our attempt at a comprehensive analysis of 200 sinonasal tumors a heterogenous and a wide variety of benign and malignant neoplasms were encountered. Rare entities like craniopharyngioma,schwannoma and osteoid osteoma among benign tumors and malignant melanoma,fibrosarcoma, metastatic clear cell carcinoma among malignant tumors were reported. To conclude, categorizing the sinonasal tumors according to histopathological features into various types helps us to understand the clinical presentation, treatment, clinical outcome and prognosis. The key in the diagnosis and treatment of sinonasal tumors remains a high index of suspicion and early diagnosis, as late presentation and delay in early diagnosis are major constraints to favourable outcome of treatment