Course of Disease and Clinical Management of Patients with Poorly Differentiated Thyroid Carcinoma

Abstract

Background: In patients with poorly differentiated thyroid carcinoma, the clinical course and prognostic value of response to initial radioiodine therapy is evaluated. Methods: In 47 patients, clinical and imaging features were analyzed. Patients were stratified in no (NED), biochemical (B-ED) and structural evidence of disease (S-ED) assessed at the first diagnostic control and its impact on survival was evaluated. Further, possible risk factors for a shorter disease-specific survival rate (DSS) were analyzed. Results: In total, 17/47 patients consisted of NED, 10/47 were B-ED and 20/47 S-ED patients. At the last follow-up, 18/47 patients were NED, 2/47 patients B-ED and 27/47 patients S-ED. The median survival time was only reached for the S-ED group (median 3.9 years, 95%CI 2.8–5.1 years) and was not reached in the B-ED and NED groups. Metastases were diagnosed by a 18F-FDG-PET/CT scan in all cases and a multivariate analysis showed that the PET-positivity of metastases was the only significant predictor of DSS (p = 0.036). Conclusion: The response to initial surgery and radioiodine therapy in PDTC patients can achieve an excellent outcome and a further follow-up should be refined based on findings at the first diagnostic control. However, patients with an incomplete response and metastatic patients who become mostly radioiodine refractory show a significantly shorter survival, which makes accurate staging by 18F-FDG-PET/CT imaging crucial.

Contrast-enhanced CT-based Radiomics for the Differentiation of Anaplastic or Poorly Differentiated Thyroid Carcinoma from Differentiated Thyroid Carcinoma: A Pilot Study

“…The primary concern in large thyroid malignancies remains DTC, which represents > 90% of all thyroid cancers 15 . However, the differential diagnosis includes ATC/PDTC, which has a poor prognosis and may require a different treatment strategy [1][2][3] . Although sonography can evaluate a thyroid mass, patients with large neck masses frequently undergo contrast-enhanced CT for differential diagnosis 15 .…”

“…Although sonography can evaluate a thyroid mass, patients with large neck masses frequently undergo contrast-enhanced CT for differential diagnosis 15 . As survival is improved by early multimodal treatments and increased use of head and neck imaging, radiologists must be familiar with the imaging features of ATC/PDTC to avoid delayed diagnosis [1][2][3]16 . ATC/PDTC usually presents as a large, heterogeneous, solid mass with increased vascularity, extensive necrosis, and local invasiveness [16][17][18] .…”

“…This study had some limitations. First, we only included 32 patients with ATC/PDTC due to the low prevalence of this entity [1][2][3] . So far, imaging studies in ATC/PDTC patients have been extremely limited.…”

“…Despite modern therapies, ATC/PDTC remains a highly aggressive disease and is the main cause of death from thyroid cancer 1-3 . Since most ATC/PDTCs are considered to arise from the dedifferentiation of differentiated thyroid cancers (DTCs), i.e., the transformation of pre-existing papillary thyroid carcinomas (PTCs) or follicular thyroid carcinomas (FTCs) into more aggressive histologic types, radiologists should be familiar with the imaging features of ATC/PDTCs to avoid delayed diagnosis [1][2][3] .Radiomics is a quantitative approach to medical imaging aimed at enhancing the data available to clinicians using advanced mathematical analysis 4,5 . Radiomics derived from the volumetric analysis of a whole tumor on contrast-enhanced computed tomography (CT) showed potential for early tumor detection, histologic grading, and predicting the recurrence of various head and neck cancers [5][6][7][8] .…”

“…Despite modern therapies, ATC/PDTC remains a highly aggressive disease and is the main cause of death from thyroid cancer 1-3 . Since most ATC/PDTCs are considered to arise from the dedifferentiation of differentiated thyroid cancers (DTCs), i.e., the transformation of pre-existing papillary thyroid carcinomas (PTCs) or follicular thyroid carcinomas (FTCs) into more aggressive histologic types, radiologists should be familiar with the imaging features of ATC/PDTCs to avoid delayed diagnosis [1][2][3] .…”