Clinico-Pathological Profile of Anaplastic Thyroid Carcinoma in an Endemic Goiter Area

Glomangiosarcoma-like Anaplastic Transformation in Papillary Thyroid Carcinoma: A Novel Form of Heterologous Differentiation and a Systematic Review of Heterologous Element Prevalence

Anaplastic thyroid carcinoma (ATC) demonstrates a wide variety of morphologies and is characteristically associated with a differentiated thyroid carcinoma component. Heterologous differentiation is a rare, potentially challenging phenomenon in ATC, mostly observed as osteosarcomatous or chondrosarcomatous differentiation. We now describe a novel 'glomangiosarcoma-like' differentiation, review our archival experience from two institutions (UPMC, CC), and perform a systematic review for the prevalence of heterologous elements in ATC. The patient is a 57-year-old female who presented with 4.5 cm left thyroid, and 3.4 cm neck masses. Histologically, the thyroid demonstrated a differentiated high grade papillary thyroid carcinoma, tall cell and hobnail/micropapillary subtypes transitioning into an anaplastic component with spindled to ovoid cells with hemangiopericytoma-like vasculature showing CD34 positivity, variable muscle marker expression and pericellular lace-like type IV collagen deposition. The neck mass consisted solely of the latter morphology. Targeted next-generation sequencing was performed on high grade DTC and adjacent ATC from the thyroid as well as ATC from the neck metastasis. All three components shared BRAFV600E, TERT promoter, and PIK3CA mutations confirming a clonal origin. Archival (UPMC: n = 150, CC: n = 74) and literature review showed no prior examples. Systematic review and meta-analysis of prevalence showed a baseline pooled prevalence (generalized linear mixed model) of heterologous elements of any type to be 1.6% (95% confidence interval: 1.0-2.6%) for studies where this was specifically addressed. ATC with glomangiosarcoma-like heterologous differentiation is a rarity among an already rare morphologic category with unique diagnostic pitfalls.

Anaplastic Cancer: Our Experience

Anaplastic thyroid carcinoma (ATC) is a rare thyroid malignancy with a dire prognosis, nearly 100% disease specific mortality and a median overall survival less than 6 months. In view of the limited data from India on anaplastic thyroid cancer, we conducted this audit to analyze the treatment pattern, outcomes and factors influencing it. This is a retrospective analysis of outcomes of patients treated in a single institution between January 2008 and December 2020. Baseline characteristics, treatment received, and outcomes among adult patients with ATC were collected. Progression free survival (PFS) and overall survival (OS) were analyzed. SPSS version 20 and RStudio version 3.1.1 were used for analysis. In this cohort of 134 patients, the median age at diagnosis was 59 years, with 63.4% of them being females. At presentation, 70.9% of them had good performance status (PS 0-1). Only 38.8% received treatment with curative intent (either surgery fb adjuvant or neoadjuvant chemotherapy fb surgery and adjuvant or definitive chemoradiotherapy) while 61.2% patients received palliative treatment (either palliation alone or palliative chemotherapy or palliative surgery or palliative RT). Predominant pattern of progression was local progression (79.8%). Median PFS and OS of the overall cohort were 58 days and 80 days respectively. PFS and OS were significantly better in patients treated with curative intent vs palliative intent (116 and 134 days vs 45 and 50 days; p = 0.00 and 0.00 respectively). Among patients treated with curative intent, OS was significantly better in patients undergoing surgery vs CTRT (155 vs 76 days; p = 0.03). Among patients treated with upfront surgery, both PFS and OS were better with the addition of adjuvant CTRT/RT vs no adjuvant (332 and 540 days vs 55 and 91 days; p = 0.00 and 0.003 respectively). ATC is a rare cancer with dismal prognosis. Local therapy with surgery followed adjuvant seems to be associated with the better outcomes. Systemic therapy seems to be a better option for palliation. Our data reflects the real world data of this rare cancer.

Revisiting Combination Chemotherapy as a Single Modality Palliative Therapy for Advanced Anaplastic Thyroid Carcinoma-a Single Institution Experience

Anaplastic thyroid carcinoma (ATC) is an aggressive malignancy with dismal outcome especially in metastatic setting. Consensus for ideal treatment of advanced and metastatic ATC remains elusive. This study aimed to analyze the impact of palliative chemotherapy versus supportive care on overall survival in patients with metastatic anaplastic thyroid carcinoma. Patients diagnosed with ATC between the period January 2018 and December 2019 were prospectively followed. The patients opting for palliative chemotherapy received 3 weekly Paclitaxel (175 mg/m²) and Carboplatin (AUC-5). Out of the 31 patients diagnosed with ATC, clinicopathological profile of 29 patients was analyzed (2 patients who underwent upfront surgical resection with curative intent were excluded), out of which 20 patients were included in the survival analysis. The median age of presentation was 55.8 years with male:female ratio 1.9:1. Seventeen out of the total 29 patients presented with anaplastic transformation in long-standing goiter. Nineteen out of 20 (95%) patients presented with distant metastasis with lungs being the most common site. Nodal metastasis was present in all patients. Invasion of the strap muscles (90%) and trachea (80%) was the most common peri-thyroidal tissue invasion followed by invasion of the esophagus (40%), internal jugular vein (30%), and carotid artery (5%). Twelve out of the 20 patients opted for palliative chemotherapy. Overall, median survival from the time of diagnosis was 2.6 months, with median survival in patients receiving chemotherapy 3.1 months and those opting for supportive care 1.6 months (p=0.004). Out of all the factors analyzed, male sex (HR 6.521, 95% CI 1.143-37.206, p value 0.03) and vascular invasion (HR 0.066, 95% CI 0.009-0.499, p value 0.008) were poor prognostic indicators. Palliative chemotherapy showed increased survival benefit in patients with metastatic ATC. Male sex and vascular invasion were found to be significant factors associated with poor outcomes on Cox regression analysis.

Effectiveness of core needle biopsy in the diagnosis of thyroid lymphoma and anaplastic thyroid carcinoma: A systematic review and meta-analysis

BACKGROUND

Both anaplastic thyroid carcinoma (ATC) and thyroid lymphoma (TL) clinically present as rapidly enlarging neck masses. Unfortunately, in this situation, like in any other thyroid swelling, a routine fine-needle aspiration (FNA) cytology is the first and only diagnostic test performed at the initial contact in the average thyroid practice. FNA, however, has a low sensitivity in diagnosing ATC and TL, and by the time the often "inconclusive" result is known, precious time has evolved, before going for core-needle biopsy (CNB) or incisional biopsy (IB) as the natural next diagnostic steps.

OBJECTIVES

To determine the diagnostic value of CNB in the clinical setting of a rapidly enlarging thyroid mass, via a systematic review and meta-analysis of the available data on CNB reliability in the differential diagnosis of ATC and TL.

METHODS

A PubMed, Embase and Web of Science database search was performed on June 23th 2021. Population of interest comprised patients who underwent CNB for clinical or ultrasonographical suspicion of ATC or TL, patients with a final diagnosis of ATC or TL after CNB, or after IB following CNB.

RESULTS

From a total of 17 studies, 166 patients were included. One hundred and thirty-six were diagnosed as TL and 14 as ATC following CNB. CNB, with a sensitivity and positive predictive value of 94,3% and 100% for TL and 80,1% and 100% for ATC respectively, proved to be superior to FNA (reported sensitivity for TL of 48% and for ATC of 61%). Furthermore, the need for additional diagnostic surgery after CNB was only 6.2% for TL and 17.6% for ATC.

CONCLUSIONS

Immediately performing CNB for a suspected diagnosis of ATC and TL in a rapidly enlarging thyroid mass is more appropriate and straightforward than a stepped diagnostic pathway using FNA first and awaiting the result before doing CNB.

Genetic Alterations in Anaplastic Thyroid Carcinoma

INTRODUCTION

Anaplastic thyroid cancer (ATC) is rare but fatal thyroid cancer responsible for majority of thyroid cancer related mortality. ATC may originate de novo or from preexisting differentiated thyroid cancer. Complex interaction between different gene mutation has been suggested to be the main causative factor for origin of ATC in both pathways. Mostly affected pathways are MAP kinase and PI3CA kinase. Hence, we decided to study the frequent alterations in both the pathways in ATC patients.

METHODOLOGY

Clinico-pathological data of 34 ATC patients were collected retrospectively and Formalin Fixed Paraffin Embedded (FFPE) blocks were taken out for genetic analysis. DNA and RANA were isolated from FFPE tissues. BRAF V600E mutations were screened by RFLP PCR method and confirmed by sequencing. RAS, PI3CA and p53 mutations were checked by sequencing. RET/PTC translocations were screened by Real Time PCR.

RESULTS

A total of 34 patients were studied: Mean age 58.6+ 11.6 years with F:M- 1.8:1, 60% had history of goiter. Most common presenting symptom was rapidly growing thyroid mass followed by dyspnea, dysphasia and hoarseness of voice. Extent of disease was local, locoregional and metastatic in 32%, 35% and 33% respectively. 57.6% were euthyroid, 20.5 % were hyperthyroid while functional status were not available in 11.7%. FNAC was suggestive of ATC only in 52.9% cases. 15 (44%) were operated. BRAF V600E mutations were observed in 10/34 (29.4%). Interestingly, all three ATC patients with DTC components had previous history of goiter with rapid increase in size and BRAF V600E mutation, while BRAF was positive only in 7/31 (22.5%) of patients with no DTC component. Mean survival of 3.5 months in BRAF positive cases in comparison to 5.5 months in BRAF negative ATC. RAS mutations were found to be positive in 5.8%, and none had RET-PTC/PI3CA mutations. P53 mutation was positive in 7 patients. 3 patients presented with history of rapid increase in size of previous goiter while rest 4 patients presented with rapidly increasing thyroid swelling of 1 to 3 months. At presentation 2 patients has disease localized to thyroid, 4 has loco-regional disease and one patient presented with metastasis. 5 out of these 7 patients were operated (Total thyroidectomy:3, thyroidectomy with neck dissection:2). Mean survival was 4 months (1-6 months).

CONCLUSION

BRAF V600E was the commonest mutation followed by p53 of the 5 genes tested and BRAF was more common in patients with previous history of longstanding goiter or differentiated thyroid cancer. This provides an indirect evidence of neoplastic transformation of PTC to ATC.