Kannan, Subramanian4; Nandini, Hamsa2;Akhila,Lakshmikantha3; Shetty, Vivek4; Kothandaraman, Srikamakshi2; Yadav, Vishal2; Kuriakose, Moni Abraham4; Chandrasekhar, Naveen Hedne4; Pillai, Vijay4
1 Consultant, Department of Endocrinology, Narayana Health City, Bangalore, India
2 Fellow, Department of Head and Neck Surgical Oncology, Narayana Health City, Bangalore, India
3 Consultant, Department of Pathology, Narayana Health City, Bangalore, India
4 Consultant, Department of Head and Neck Surgical Oncology, Narayana Health City, Bangalore, India
Background: Spindle epithelial tumor with thymus like differentiation (SETTLE) tumors of thyroid are rare.
Case report: A 66 year old gentleman with coronary artery disease presented with a right sided neck mass which was present for more than ten years but he noted considerable increase in size for past two years. Initial core biopsy of the neck mass was reported as a spindle cell tumor. Neck ultrasound revealed a large hypoechoic mass with irregular borders and multiple areas of macrocalcifications. There were no suspicious lymph nodes. Serum calcitonin and serum carcinoembryonic antigen were normal. CT scan showed a mass infiltrating the right lobe of thyroid, encasing the right common carotid artery and brachiocephalic vessels with tumor embolus in right IJV and SVC. The patient underwent right hemithyroidectomy, mass excision and coronary artery bypass grafting.
Results: The gross pathology showed a fleshy, nodular, soft to firm tumor involving the entire right thyroid lobe. On microscopy there were sheets of bland tumor cell spindle shaped with oval elongated nucleus, inconspicuous nucleoli, ill defined cytoplasmic borders. Mitotic figures are very rare but multiple foci of calcifications were seen. Admixed were few glandular areas lined by low cuboidal epithelium with central eosinophilic material admixed are very a few mature lymphocytes consistent with the diagnosis of SETTLE. At 4 months post treatment, the patient is doing well with no evidence of locoregional or distant disease. Long term follow-up is mandatory due to their propensity for late distant metastasis.
Conclusion: We report the oldest case of SETTLE tumor of the thyroid.