BACKGROUND: Here, we report a case of a postoperative spindle cell nodule that mimicked recurrence with anaplastic transformation after thyroidectomy. METHODS: The course of the disease is described. The mass was studied morphologically and immunohistochemically. RESULTS: A 31-year-old woman underwent total thyroidectomy for papillary thyroid carcinoma. A mass suspected of recurrence was found 14 months later and caused dysphagia and dyspnea. An (18)F-fluorodeoxyglucose positron emission tomographic ((18)F-FDG-PET) scan showed a lesion with high uptake; however, a fine-needle aspiration biopsy (FNAB) was inconsistent with recurrent cancer. The mass was resected and was composed of elongated spindle cells, with eosinophilic cytoplasm within a myxoid background. Immunohistochemical staining was strongly positive for vimentin, focally positive for smooth muscle actin, desmin, and p53, and negative for cytokeratin AE1/AE3, Cam5.2, epithelial membrane antigen (EMA), and anaplastic lymphoma kinase (ALK-1). CONCLUSION: Although postoperative spindle cell nodules are rare after thyroid surgery, it should be considered in the differential diagnosis for recurrent masses at the operative site.
BACKGROUND: Here, we report a case of a postoperative spindle cell nodule that mimicked recurrence with anaplastic transformation after thyroidectomy. METHODS: The course of the disease is described. The mass was studied morphologically and immunohistochemically. RESULTS: A 31-year-old woman underwent total thyroidectomy for papillary thyroid carcinoma. A mass suspected of recurrence was found 14 months later and caused dysphagia and dyspnea. An (18)F-fluorodeoxyglucose positron emission tomographic ((18)F-FDG-PET) scan showed a lesion with high uptake; however, a fine-needle aspiration biopsy (FNAB) was inconsistent with recurrent cancer. The mass was resected and was composed of elongated spindle cells, with eosinophilic cytoplasm within a myxoid background. Immunohistochemical staining was strongly positive for vimentin, focally positive for smooth muscle actin, desmin, and p53, and negative for cytokeratin AE1/AE3, Cam5.2, epithelial membrane antigen (EMA), and anaplastic lymphoma kinase (ALK-1). CONCLUSION: Although postoperative spindle cell nodules are rare after thyroid surgery, it should be considered in the differential diagnosis for recurrent masses at the operative site.
Authors: David Suster; Michael Michal; Michiya Nishino; Simonetta Piana; Massimo Bongiovanni; Olga Blatnik; Veronika Hájková; Nikola Ptáková; Michal Michal; Saul Suster Journal: Mod Pathol Date: 2020-04-14 Impact factor: 7.842