Development and validation of a nomogram to predict overall survival in patients with redefined anaplastic thyroid carcinoma based on the SEER database.

BACKGROUND: According to the latest classification of thyroid tumors released by the WHO in 2022, primary squamous cell carcinoma of the thyroid (PSCCTh) is classified as anaplastic thyroid carcinoma (ATC). The objective of this study was to determine the differences in characteristics between ATC and PSCCTh and develop a nomogram to predict overall survival patients with the redefined anaplastic thyroid carcinoma (rATC). METHODS: Patients diagnosed with ATC and PSCCTh between 2000 and 2018 from the Surveillance, Epidemiology, and End Results (SEER) database were enrolled and randomly divided into a training cohort and a validation cohort with a ratio of 7:3. Overall survival (OS) and cancer-specific survival (CSS) was estimated using the Kaplan-Meier method and compared using log-rank tests. The univariate and multivariate Cox proportional hazards regression analyses were used to determine independent prognostic factors of rATC patients. We then developed and validated nomograms to predict the 3-, 6- and 12-month OS of rATC and the results were evaluated by C-index and calibration curves. RESULTS: After application of the inclusion and exclusion criteria, a total of 1338 ATC and 127 PSCCTh patients were included in the study. Further, OS and CSS of patients with PSCCTh were better than that of patients with ATC. Prognostic factors were not identical for the two cancers. Multivariate Cox model analysis indicated that age, tumor size, metastasis, surgery, radiotherapy, chemotherapy are independent prognostic factors for CSS in patients with ATC; while for patients with PSCCTh, the corresponding factors are age, and surgery. We selected six survival predictors (age, tumor size, metastasis, surgery, radiation, and, chemotherapy) for nomogram construction. The C-indexes in the training and validation cohort were 0.740 and 0.778, respectively, reflecting the good discrimination ability of the model. The calibration curves also showed good consistency in the probability of 3-, 6-, and 12-month OS between the actual observation and the nomogram prediction. CONCLUSION: We constructed a nomogram to provide a convenient and reliable tool for predicting OS in rATC patients. Prognostic factors influencing CSS were not identical in patients with ATC and PSCCTh. These findings indicate that different clinical treatment and management plans are required for patients with these two types of thyroid cancer.

Paraneoplastic Manifestation of Primary Squamous Cell Cancer of the Thyroid Gland.

Paraneoplastic manifestation (PNM) of cancers is a non-metastatic, non-invasive systemic effect of malignancies due to chemokines and hormones produced by the primary neoplasm. Squamous cell cancers (SCCs) are known to present with PNM. Primary SCC of thyroid accounts for <1% of all thyroid malignancies and carries a very poor prognosis. We present a rare case of SCC arising from the thyroid gland who presented with fever, leukemoid reaction and hypercalcemia as part of PNM. A 67-year-old male patient presented with two months history of intermittent high-grade fever, weakness, loss of weight and appetite. Examination revealed a large (~10 cm) hard swelling over the right side of the neck. Investigations revealed neutrophilic leukocytosis, elevated C-reactive protein (CRP) and procalcitonin and hypercalcemia with a normal thyroid-stimulating hormone (TSH). The fever workup was negative for infection. Fine-needle aspiration cytology (FNAC) and core biopsy of the thyroid mass revealed malignant cells with squamous differentiation. An extensive search for possible other primary was ruled out by triple endoscopy. The combination of fever, neutrophilic leukocytosis, hypercalcemia and squamous malignancy was consistent with a diagnosis of PNM of SCC. A fluorodeoxyglucose-positron emission tomography (FDG-PET) CT scan showed a heterogeneously enhancing mass lesion in the right lobe of the thyroid with some retrosternal extension. He underwent total thyroidectomy with bilateral central compartment neck dissection. Final histopathology revealed moderately differentiated SCC of the thyroid. Concurrent chemoradiation was given. Despite continued chemotherapy, he succumbed to illness within six months of diagnosis. Primary SCC of thyroid (PSCCT) is a rare malignancy. It is a highly aggressive tumor having a poor prognosis with a median survival time of about 9-12 months and less clearly defined therapy due to its rarity. Paraneoplastic manifestation of PSCCT is known. As fever, leukemoid reaction and hypercalcemia can be a paraneoplastic manifestation, one should think of PSCCT.

Two Cases with Squamous Cell Carcinoma of the Thyroid Gland / 대한내분비학회지

Primary squamous cell carcinoma of the thyroid is rare, presenting much less than one percent of all primary thyroid malignancies. Most cases have been reported in elderly patients with a history of goiter. It is necessary to differentiate between primary squamous cell carcinoma and secondary involvement from other sites. Secondary involvement of the thyroid may be more amenable to palliation or cure. The treatment of choice in primary squamous cell carcinoma is radical surgery in resectable cases, but the squamous cell carcinoma behaves aggressively and carries a uniformly poor prognosis regardless of the treatment. We had an experience of a primary squamous cell carcinoma of the thyroid in two elderly patients. These patients presented a typical feature of a primary squamous cell carcinoma of the thyroid, which has been rarely reported in Korea.