 Good morning everybody. Myself Dr. Vishesh Koshik, I am from Pandit Bhagavad-Gyayal Sharma, Post-Private Institute of Medical Sciences, Rohtak. I am presenting a case of neuroendocrine tumor of the tonsillar fossa. The objective is to present a rare case of tonsillar neuroendocrine tumor and establish its imaging features and extensions. Introduction Tonsill is one of the most common sites from where primary oropharyngeal tumor arise. The most common tumor in this area is squamous cell carcinoma, vial, minus levary gland tumors, lymphomas, melanoma and sarcomas are also included. The incidence of neuroendocrine tumor of head and neck is low and mainly arises in the larynx followed by salivary glands, nose and peronazole sinuses. According to the latest WHO classification of head and neck tumors, typical and atypical carcinoid are well differentiated neuroendocrine cancers and small cell neuroendocrine cancer is classified as poorly differentiated tumor. Large cell neuroendocrine cancer is also a poorly differentiated tumor which has been well established in the pulmonary neuroendocrine tumors, but whether it should be refined as a distinct entity in neuroendocrine tumors of head and neck is still under debate. Aim To study the role of imaging in a neuroendocrine tumor of tonsill which is an extreme rarity. Through imaging, the extent of the tumor and its relation with the adjacent structures can be described which can further help to narrow down differentials and decide method of treatment. Case History A 48-year-old male chronic smoker was referred to the radiology department for CECD neck with history of neck swelling on left side and throat pain since 3 months. History of odinophagia was present, physical examination revealed left-sided ulceroproliferative growth with fullness in anterior tonsillar pillar. Neck pellet and tonsill was normal, multiple palpable lymph nodes were present on left side, CCT, CMRI and USC examination of the patient was performed, biopsy of the tonsillar mass was taken and sent for histology. Imaging Findings CECD neck was performed on a 16-slice machine, it showed an ill-defined, heterogeneously announcing soft tissue lesion in the left tonsillar fossa with few hyperdense foci which was the destiny of tonsillolith. Anteriorly, the lesion was involving base of tongue left side and inferiorly, the lesion was involving the left lateral pharyngeal wall. Left velecula was partially obliterated. Multiple heterogeneously announcing lymph nodal masses were seen at level 2, 3, 4 and 5 on the left side. Major neck vessels, recto-pharyngeal space, bilateral parotid and some endemic lands were unremarkable. So these are the images. In these axial sections and corneal section, we can see a heterogeneously announcing mass lesion in the left tonsillar fossa. In this corneal section, we can see multiple lymph nodes along the left jugular digustic chain. CEMRI was also performed on 3-tesla system, contrast enhance images were acquired in T1-weighted, T2-weighted and diffusion-weighted sequences in axial societal and corneal planes. The well-defined lesion was seen in left tonsillar fossa which was hyperintensive on T1-weighted and hyperintensive on T2-weighted imaging. On post-contrast scan, slight peripheral enhancement was noted. The lesion was also involving jugular and extending into the left velecula. It appeared to be involving the left postural aspect of base of tongue. Multiple announced lymph nodes showing single intensity similar to the lesion were seen in the left cervical and supra-clavicular area. So in this T2-axial sequence, we can see a hyperintense lesion involving the left tonsillar and also involving the postural lateral aspect of tongue. There are lymph nodes which are showing the same single intensity as of the lesion. On DWI, there was evidence of restriction. In this corneal imaging, the lesion is T2-hyperintense. So these are the contrast enhance actions. In this corneal image, the lesion is showing peripheral enhancement. These are the lymph nodes. These are also showing peripheral enhancement. In this societal section, the lesion seems to be involving the base of the tongue. Ultrasound neck showed multiple necrotic lymph nodes on left side of the neck. USG abdomen showed multiple round target lesion such as T2-lever metastasis. All the imaging features were in favor of neoplastics of tissue mass of left tonsillar fossa with metastatic, cervical nephrenopathy and liver metastasis. Finally, the biopsy was done. An histopathology revealed neuroendocrine carcinoma of the left tonsillar fossa on immunohistochemistry tumor cells were CK-positive which showed dot-like positivity, chromo-grinding neck-positive, P63-negative. So these are the ultrasonic images. In this, the liver shows multiple target-shaped lesions of variable sizes scattered throughout the liver, which were suggestive liver meds. And this image shows necrotic lymph nodal mass on the left side of the neck. Discussion Neuroendocrine carcinoma is an epithelial malignancy with neuroendocrine differentiation which has been reported many organs throughout the body. NEC of the oropharynx is rare. Immunohistochemistry analyses usually demonstrate the positive staining for general neuroendocrine markers including synaptophysin, CD56 and chromogranil. This evidence suggests that oropharyngeal neuroendocrine cancer is more aggressive than the more commonly-encouraged carcinoma with the poorer prognosis. It has a propensity to develop early regional lymphatic and systemic metastasis, therefore should be considered a systemic disease from the outside. The treatment of the extra pulmonary neuroganate tumor depends on whether the tumor is tractable, local regionally advanced but unresectable or metastatic. Even with small cell tumors are more likely to receive chemo-radiation as the primary treatment modality while those with other neuroendocrine tumor types are more likely to undergo surgical resection. To conclude, in this particular case, patient came with history of neck swelling left side. Imaging features were suggestive of malignant mass left tonsilophosa with cervical nodal and liver metastasis. On histopathology, the mass turned out to be neuroendocrine carcinoma, which is a rare entity. Imaging helped us to see the extension of the tumor, its relation with adjacent structures and local regional and distant metastasis, which is important for planning the treatment. Here are the references. Thank you very much.