RET gene mutation is seen in which malignancy -

(B) (Medullary carcinoma thyroid (280, 728-29 Robins 8th) 815 Harsh Mohan 6th)Medullary thyroid carcinoma* RET proto-oncogene is a growth factor receptor (receptor tyrosine kinase)* The RET protein is a receptor for the glial cell lined derived neurotrophic factor and structurally related proteins that promote cell survival during neural development.* RET proto-oncogene located on chromosome 10q.* Familial MTC occurs in MEN-2**, peculiar features is - multicentric C cell hyperplasia.* Amyloid deposits**, derived form altered calcitonin** molecular, in some cases, the tumor cells elaborate other polypeptide hormone such as serotonin, somatostatin, VIP.* MTC are neuroendocrine neoplasms derived from the parafollicular cells or C-cells.* Patients with MTC often present with neck mass may be associated with palpable cervical lymphadenopathy** early spread to lymphatics is common.* Distal blood borne metastasis** to the liver, bone (frequently osteoblastic) and lung occur late in the disease.* MTC tumour do not take up radioiodine and hormone dependent**.* Radiation induced thyroid carcinoma is papillary carcinoma (Latent period about 30 years).* Tadpole cells comma shaped cells or strap cells on histopathology are seen in Rhabdomyosarcoma.* Germline mutations in CDH1, which encodes E.Cadherin - associated with gastric carcinoma.* Follicular thyroid carcinoma is differentiated with follicular adenoma with - capsular invasion.* Rokitanskiprotuberance are seen in mature being teratoma.* SYT-SSXI gene is associated with synovial sarcoma.* Primary CNS lymphoma is the most common CNS neoplasms in immuno-suppressed patients including those with AIDS and immuno-suppression after transplantation (B-cell lymphomas) most common locations are the frontal lobes, followed by deep nuclei and periventricular zone.* Squamous cell carcinoma marker is cytokeratin.* Most common site of glioblastoma multiforme is temporal and frontal lobe and basal ganglia medulloblastoma a site is cerebellum.* Patients with familial retinoblastoma are at increased risk of developing osteosarcoma.* Mucoepidermoid carcinoma is most common malignancy of salivary gland.* Most common malignancy offalopian tube is serous carcinoma.* Marginal zone lymphoma is B-cell type non-hodgkinfs lymphoma.Papillary carcinoma of thyroid:- Associated with dystrophic calcification- Psammoma bodies- Orphan Annie-eyed nuclei- Best prognosis and most common thyroid carcinoma* Follicular carcinoma*** would occur in prolonged multi-nodular goitre* Treatment of choice for solitary thyroid nodule is hemithyroidectomy (lobectomy + isthmusectomy).* Most common cause of solitary thyroid nodule is Benign colloid nodule (1) Benign follicular adenoma**.