Fine-Needle Aspiration with Immunohistochemistry Using a Modified Scrape Cell Block Technique for the Diagnosis of Thyroid and Parathyroid Nodules

Abstract

Objective: To evaluate the diagnostic accuracy of a modified scrape cell block (SCB) technique in a large series of patients. The technique was especially developed and tested for fine-needle aspiration of thyroid and parathyroid nodules. Study Design: Eighty-two ultrasound-guided fine-needle aspiration specimens with the sonographic aspect of a thyroid (n = 33) or a possible parathyroid nodule (n = 49) were studied. Immunohistochemistry (IHC) was used on cell blocks containing plasma, thromboplastin, and selected 3-dimensional cell aggregates scraped off Papanicolaou-stained smears. Antibodies for chromogranin A, thyroglobulin, parathyroid hormone, calcitonin, and carcinoembryonic antibody (CEA) were used. In cases of reduced immunosensitivity or suspected metastases or rare primary tumors, additional IHC markers were employed. Results: Chromogranin A was expressed in all 28 parathyroid adenomas (PA), in 7 of 8 hyperplastic parathyroid glands, and in 13 of 14 medullary thyroid carcinomas (MTC). When combining positivity for chromogranin A and calcitonin/CEA, the specificity for the detection of MTC was 100%. Parathyroid hormone was expressed in 26 of 36 parathyroid nodules (72.2%). When combining follicular microarchitecture and expression of chromogranin A, the specificity for the detection of parathyroid tissue was 97%. Conclusion: With the modified SCB technique, accurate cytological diagnoses were obtained in 97.6% of 82 patients.

A Nationwide Study of Multiple Endocrine Neoplasia Type 2A in Norway: Predictive and Prognostic Factors for the Clinical Course of Medullary Thyroid Carcinoma

“…By adding immunocytochemistry (IHC), including calcitonin on slides processed by thin layer cytology, the sensitivity in diagnosing MTC highly improves (116,118). Furthermore, FNB with IHC on cell blocks gives the MTC diagnosis with more than 95% sensitivity (119). A positive stain of calcitonin in IHC is diagnostic for MTC in thyroid tumors, as well as a positive stain for carcinoembryonic antigen (CEA), as they are negative in other thyroid tumors.…”

“…At elevated calcitonin and negative cytological examination, cytological cell-block with immunohistochemistry improves the diagnostics (119). Core-needle biopsy, if possible, is an alternative.…”

Manufactured Cell Blocks: Turning Smears into Sections

“…This approach has previously been reported by Bhatia et al [2] and Kulkharni et al [1] who obtained adequate material in 26 of 27 (96%) and in 17 of 17 (100%) cases, respectively. Wuertz et al [3] similarly described good results with the modified scrape cell block technique performed on selected FNA of thyroid and parathyroid nodules (97.6% in 82 cases). Our results are comparable to these reports: 163 of 178 cases (91.6%).…”

“…We used air-dried and/or fixed smears, whilst Bhatia et al [2] as well as Wuertz et al [3] only performed mCB on fixed smears and Kulkharni et al [1] did not record which type of smears they used . The choice of slide was dependent on the amount of cellular material on the available slides and the majority of our cases were performed on air-dried smears: 156 of 179 cases (87.1%).…”

Thyroid Nodules in Diagnostic Pathology: From Classic Concepts to Innovations

“…Neuroendocrine differentiation is the hallmark of MC that is positive for chromogranin A in 92.9% of cases [100]. Regarding the other regional causes of chromogranin A-positive mass lesions, parathyroid adenoma (that can occur intrathyroidally) and parathyroid hyperplasia are characterised by expression rates of 28/28 and 7/8 [100].…”