<unk>  can resemble small blue cell tumors like squamous cell carcinoma, sinonasal undifferentiated carcinoma, extranodal NK/T cell lymphoma, nasal type, rhabdomyosarcoma, Ewing/PNET, mucosal malignant melanoma and neuroendocrine carcinomas (NEC) that occur in the intranasal tract. Compared to other tumors in the region,<unk>  has the best prognosis, with an overall 5 year survival rate of 60-80%. Fewer than 700 cases have been documented in the United States alone.<unk>  is characterized by neurofibrillary stroma and neurosecretary granules that are not seen concurrently by any other pathologies in the region. Histological tests such as keratin, CK5/6, S-100 protein or NSE can be run to further differentiate<unk>  from other tumors. Staging The Kadish classification is used for clinical classification of sinonasal tumors including<unk> . Subsequent research articles have been published to determine prognosis based on tumor grade. Modified Kadish classification Stage Description 5 year survival A Tumor confined to nasal cavity 75-91 B Nasal cavity and paranasal sinuses 68-71 C Tumor extends beyond nasal cavity and paranasal sinuses, including skull base, orbit or cribiform plate 41-47 D Tumor metastasizes to cervical lymph nodes and beyond <40 Dulguerov classification Stage Characteristics T1 Tumour involving the nasal cavity and/or paranasal sinuses (excluding sphenoid), sparing the most superior ethmoidal cells T2 Tumour involving the nasal cavity and/or paranasal sinuses (including the sphenoid) with extension to or erosion of the cribriform plate T3 Tumour extending into the orbit or protruding into the anterior cranial fossa, without dural invasion T4 Tumour involving the brain N0 No cervical lymph-node metastasis N1 Any form of cervical lymph-node metastasis M0 No metastases M1 Distant metastasis
Esthesioneuroblastoma
Ganglioneuroblastoma
Nesidioblastoma
Neuroma
Mycetoma
Hamartoma
Neurofibroma
Melanocytoma