Application of GATA 3 and TTF-1 in differentiating parathyroid and thyroid nodules on cytology specimens.

BACKGROUND: Differentiating parathyroid from thyroid lesions can be difficult on fine-needle aspiration (FNA) due to overlapping cytomorphologic features. While the traditional parathyroid hormone (PTH) assays can help in the distinction, these tests may be cumbersome, particularly when the lesion is unexpected clinically and a needle wash is not collected at the time of FNA. Therefore, we chose to investigate the application of immunohistochemical staining (IHC) with GATA 3 and thyroid transcription factor-1 (TTF-1) on air-dried cytology smears to distinguish parathyroid and thyroid lesions. METHODS: Air-dried touch preparation (TP) slides were prepared from consecutively selected parathyroid and thyroid specimens. Thirteen FNA cases with the clinical concern for parathyroid lesions were also included in the study. IHC was performed on unstained and ultrafast Papanicolaou (UFP) stained air-dried slides. RESULTS: On TP slides, GATA 3 expression was observed in all cases of parathyroid origin but no immunoreactivity was present in thyroid lesions. TTF-1 expression was observed in all cases of thyroid origin but not in parathyroid lesions. GATA 3 and TTF-1 expression of 13 FNA cases were consistent with the clinical impression or concurrent PTH tests. CONCLUSIONS: IHC with GATA 3 and TTF-1 on air-dried cytology smears is a simple and effective way to differentiate parathyroid vs thyroid lesions on FNA. Air-dried unstained and UFP-stained slides perform equally well with IHC, but UFP-stained slides provide the added benefit of morphologic evaluation and assessment of smear cellularity prior to IHC.

Self-clotting method improves cell block preparation.

BACKGROUND: The success of cell block preparation is crucial for ancillary diagnostic tests in cytology. However, achieving an optimal cell block can be challenging. The current study describes a self-clotting-based technique for fine-needle aspiration (FNA) cell block preparations and evaluates its usefulness in comparison with the conventional needle wash technique. METHODS: The clinical data, FNA procedure, and cellularity of cell blocks of the self-clotting group (37 cases) and the conventional needle wash group (33 cases) were compared. The cellularity was evaluated using a scoring system (0 indicated acellular, 1 indicated 1-50 cells, and 2 indicated >50 cells). RESULTS: Approximately 76% of cases in the self-clotting group received a score of 2 versus 36% in the conventional needle wash group. Approximately 14% received a score of 1 in the self-clotting group compared with 9% in the conventional needle wash group, whereas 11% in the self-clotting group received a score of 0 versus 55% in the conventional needle wash group. The differences between the 2 methods were statistically significant. CONCLUSIONS: The results of the current study demonstrate that the self-clotting method is superior to the conventional needle wash method for FNA samples. Cancer Cytopathol 2018;126:190-9. © 2017 American Cancer Society.

Chondroid syringoma of the axilla: An unusual tumor diagnosed by fine needle aspiration.

Chondroid syringoma (CS) is a rare benign adnexal tumor of the skin with a resemblance to pleomorphic adenoma of salivary gland, most commonly involving the head and neck region. In the present literature, reports of the cytologic appearance of CS are scarce as it is rarely encountered by fine needle aspiration (FNA). A 67-year-old woman presented with a 1 year history of a 1 cm subcutaneous nodule in the right axilla. FNA biopsy was performed revealing an epithelial-mesenchymal biphasic neoplasm suggesting CS. Surgical excision confirmed the diagnosis and demonstrated extensive ossification, an extremely rare feature, with only seven reported cases, all located on the head. CS is a rare benign adnexal tumor of the skin, often overlooked due to its unremarkable clinical presentation. FNA is a reliable tool for the diagnosis of CS and helps guide optimal surgical management.

Mucinous tubular and spindle cell carcinoma of the kidney: Diagnosis by fine needle aspiration and review of the literature.

Renal mucinous tubular and spindle cell carcinoma (MTSCC) was recently described as a distinct subtype of renal cell carcinoma (RCC) in the 2004 World Health Organization classification of kidney tumors. MTSCC is a rare low grade malignancy with < 100 cases reported in the literature. To the best of our knowledge, there are 5 case reports with a total of 6 patients describing its diagnosis by fine needle aspiration (FNA). All of these cases were diagnosed as conventional RCC on FNA. Subsequent excisions proved them to be MTSCC. We herein report a case in a 67-year-old male. He presented with abdominal pain and was found to have a new colon adenocarcinoma with metastasis to the liver and lungs. The extent of disease made the patient ineligible for surgical excision, and he received chemotherapy. Work-up also revealed a kidney mass which was later biopsied by FNA and core biopsy. The tumor was composed of epithelial and spindled cell components embedded in a myxoid background. It was positive for CK7, AMCAR, vimentin, and epithelial membrane antigen. The tumor was diagnosed as MTSCC. One year later the kidney mass remained stable. However, the patient developed new metastasis to the liver from colonic primary. The kidney mass was not resected. Although rarely encountered in FNA cytology of the kidney, we believe the cytologic features of this tumor are distinctive and are different from conventional and other subtypes of RCC. Therefore, its accurate diagnosis on FNA is possible once pathologists are aware that MTSCC should be considered in the differential diagnosis of kidney tumors.

A case of highly aggressive extraskeletal myxoid chondrosarcoma.

Extraskeletal myxoid chondrosarcoma (EMC) is a soft tissue malignancy characterized by specific chromosomal abnormalities involving the TEC gene. This disease has historically been considered largely indolent both histologically and clinically. Rarer subsets of EMC exist that demonstrate aggressive histopathologic features and clinical behavior, though it remains unclear whether or not aggressive histopathology is predictive of outcome. Herein we present a case of EMC with aggressive histopathologic features that underwent rapid clinical progression despite initial treatment with curative intent. This case provides the context for a discussion of the existing literature regarding treatment, prognosis, pathology, and genetic/molecular features of EMC in general and aggressive EMC specifically.

Myositis ossificans within the intercondylar notch treated arthroscopically.

We present a case of intraarticular myositis ossificans in the right knee of a child. Myositis ossificans (MO), though relatively rare in childhood and even more uncommon within a joint, should be included in the differential diagnosis of an intra-articular mass when indicated by the typical clinical, radiographic, and histologic findings. An 11-year-old male presented with a history of trauma to his right knee. Four weeks after the initial injury, an MRI demonstrated evidence of an ACL rupture with a "cystic mass" within the intercondylar notch along the anterior surface of the torn ligament. At subsequent arthroscopy, the mass noted on MRI was removed. The histology was consistent with MO. The authors believe this to be the first case of MO in the intercondylar notch detected by MRI, treated by arthroscopy, and confirmed by histology.

Reparative change with extensive squamous metaplasia: a potential diagnostic pitfall on thyroid aspiration.

Squamous metaplasia and cystic change can appear in the thyroid and mimic a variety of lesions. In this report, a patient with two dominant left thyroid nodules underwent fine needle aspiration (FNA) biopsy for each nodule. One of the nodules was diagnosed as consistent with papillary carcinoma and the other as suspicious for papillary carcinoma. Subsequent near total thyroidectomy revealed both lesions to be part of a goiter with extensive squamous metaplasia. This article discusses a potential pitfall in the interpretation of fine needle aspirates of squamous metaplastic cells in the thyroid.