In the Basis of Hashimoto’s Thyroiditis, to Form Papillary Thyroid Carcinoma, Metastasized and Then to De-Differentiate into Poorly Differentiated Squamous Cell Carcinoma

Thyroid squamous cell carcinoma is very rare. At present, it is limited to case reports. Since the thyroid follicular epithelium is the non-squamous epithelium, how primary squamous cell carcinoma (SCC) of the thyroid occurs is still a controversial issue. Hashimoto’s thyroiditis (HT) is considered to be an independent risk factor for thyroid cancer, under the basis of HT, how tumor cells evolve and develop to papillary thyroid carcinoma (PTC), and particularly to de-differentiate into SCC is elusive. We report a 72-year-old female patient who developed multiple subtypes of PTC on a basis of HT, and finally to de-differentiate into SCC within the local foci of lymph node metastasis. We found that there was a variety of sub-types of PTC in this patient in the background of HT. SCC was found within local lymph node metastasis. Pathomorphology, immunohistochemistry, and molecular pathology have confirmed that the SCC was derived from PTC, and then developed into poorly differentiated SCC and/or anaplastic carcinoma. We also conducted a comprehensive literature review.

Thyroid follicular renal cell carcinoma excluding thyroid metastases:A case report

BACKGROUND Thyroid follicular renal cell carcinoma is a special type of renal cell carcinoma newly recognized in recent years.It has attracted attention because of its unique histology,immunophenotype,and clinical characteristics.It has a very low incidence,and the number of case reports available for review is limited.Moreover,a thyroid mass with type of tumour is rare.CASE SUMMARY We report a case of a renal mass with a bilateral thyroid mass that was accidentally discovered in a 60-year-old man during physical examination.B-mode ultrasound showed a hypoechoic mass in the middle and lower parenchyma of the right kidney,and computed tomography showed an iso-density shadow tumour in the right kidney.Contrast agents had a significant continuous enhancement effect on the tumour,and the enhancement was not uniform.After partial nephrectomy,pathological analysis was performed to rule out the possibility that the renal tumour was caused by thyroid tumour metastasis.Needle biopsy of the thyroid tumour confirmed that the renal cell carcinoma was not related to the thyroid tumour.The patient was alive at the last postoperative follow-up.CONCLUSION This is the third published case in which thyroid tumour biopsy was performed to confirm that thyroid follicular renal cell carcinoma is not thyroid related.

Fine-needle aspiration cytology of an intrathyroidal nodule diagnosed as squamous cell carcinoma: A case report

BACKGROUND Both squamous cell carcinoma(SCC)and papillary thyroid carcinoma(PTC)are common malignant tumors in the neck.However,seldom has SCC of the thyroid been diagnosed.Further,cytological features of SCC and PTC have rarely been reported.The significance of fine-needle aspiration cytology(FNAC)in the diagnosis of neck masses has been established.Herein,we present an exceedingly rare case of an intrathyroidal SCC diagnosed using FNAC,along with its cytological features.CASE SUMMARY A 66-year-old man presented with a left-sided neck mass.Ultrasound examination showed an ill-defined nodule.The appearance was hypoechoic with a few hyperechoic spots.FNAC of the left thyroid nodule was performed.A cellular smear was obtained,and it showed a large number of neoplastic cells with rich cytoplasm and poor cell adhesion.Tumor cell nuclei showed coarse nuclear chromatin and a few enlarged prominent nucleoli.An increased nuclear/cytoplasm ratio was observed.Thus,malignancy was diagnosed without a confirmed tumor type.Percutaneous tumor biopsy was performed to make a definite diagnosis.The tumor cells showed typical squamous cell characteristics.CONCLUSION Head and neck SCC and PTC have different cytologies.Measures are needed to ensure accurate diagnosis using FNAC.