Difficulties in diagnosis of Riedel's thyroiditis on aspiration cytology: A case report and brief review of the literature

Abstract

Riedel's thyroiditis (RT) is a rare disorder characterized by extensive fibrosis extending to the extrathyroidal tissues. An elderly male presented with diffuse moderate thyromegaly and hoarseness of voice for two years. Radiology showed extrathyroidal extension around trachea with compression and deviation suggestive of malignancy. Thyroid was hard and non tender. Ultrasound guided Fine Needle Aspiration (FNA) from multiple foci on both sides using thinner needle yielded moderately cellularity showing follicular cells, lymphoplasmacytic infiltrate, scant colloid and fibrous tissue fragments. Hurthle cells were absent. Adiagnosis of chronic thyroiditis was given with possibility of RT in view of clinical and radiological findings. A core biopsy showed similar picture as cytology. Guided FNA from multiple foci using thinner needle helped to obtain adequate material allowing a confident diagnosis. This case adds to the meagre literature available on the cytologic diagnosis of RT and highlights the diagnostic challenge due to suspicious radiology findings.

Reshaping the Concept of Riedel’s Thyroiditis into the Larger Frame of IgG4-Related Disease (Spectrum of IgG4-Related Thyroid Disease)

“…Since 2019, nine case reports of a single patient per paper have been published according to our methods [ 6 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ] ( Table 2 ).…”

“…Serum IgG4 might not be increased in local (thyroid) forms of RT (with no other spreading of IgG4-RD) while immunohistochemistry provides a meticulous insight into IgG4-positive staining, which provides a clue regarding the specific case (regardless of the concentration of the serum IgG4 profile) [ 45 ]. Five out of the nine single case reports had a serum IgG4 assay available (only 2/5 had higher than normal values), while all subjects had a histological confirmation of the condition [ 6 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ].…”

“…Navarro-Sánchez et al [ 48 ] described the case of a 69-year-old female who was treated only with tamoxifen (20 mg per day for 2 months) in addition to levothyroxine replacement (100 µg per day) for hypothyroidism and registered an excellent response [ 48 ]. Of course, all the subjects admitted with a history of hypothyroidism, with RT-induced hypothyroidism, or those who developed post-thyroidectomy hypothyroidism received lifelong levothyroxine replacement [ 6 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ].…”

Reidel’s Thyroiditis, a Diagnostic and Management Challenge: A Case Report and Review of the Literature

“…Although numerous imaging techniques have been used, clinicians remain unable to differentiate Riedel's thyroiditis from other thyroid pathologies, including neoplasms [8]. Cytology is not always diagnostic in RT and may fail to prove the invasive nature of fibrosis [9]. e diagnosis of RT is most commonly suggested after pathologic evaluation of resected thyroid tissue.…”

Indications for hemithyroidectomy for nodular goiteragainst the background of autoimmune thyroiditis and prognosis of long-term results

“…Хоча точність морфологічної діагностики вузлової трансформації ЩЗ у пунктатах становить 96,0-98,0 %, на тлі АІТ точність морфологічної діагностики вузлових утворень знижується О. В. [11,12]. Важливою складовою діагностики є встановлення розладів регуляції клітинного циклу, зокрема апоптозу і проліферації.…”