Faculty Bibliography

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.

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 2017. (c) 2017 American Cancer Society.

Introduction: The success of cell block preparation is crucial for ancillary diagnostic tests in cytology. However, achieving an optimal cell block can be challenging. We observed that cell block cellularity is best in cases with visible blood clots in the fine-needle aspiration (FNA) needle wash solution. Therefore, we hypothesized that the adequacy of cell block preparation will improve if FNA aspirates are allowed to first form a clot in the collection tube. Materials and Methods: We created a modified cell block preparation technique allowing FNA samples to clot in a dry tube prior to addition of any liquid media or further cell block preparation (Figure 1). The clinical data, FNA procedure and the cellularity of cell blocks of the clotting group (37 cases) and the conventional needle wash group (33 cases) were compared. Cellularity was evaluated using a scoring system (0 = acellular, 1Z 10 - 50 cells, 2 = > 50 cells). Results: 28 cases (78%) received a score of 2 in the clotting group compared to 12 (36%) in the conventional needle wash group. 5 (15%) received a score of 1 in the clotting group compared to 3 (9%) in the conventional group; 4 received a score of 0 (11%) in the clotting group versus 18 (55%) in the conventional group. The difference in cell block cellularity between the two methods was statistically significant (p < 0.001) (Figure Presented) (Table 1). Immunohistochemistry (15 cases) and molecular analyses (2 cases) was performed in the clotting group compared to 10 and 1 case, respectively in the conventional group. Conclusions: Our study demonstrates that clotting method is superior to the conventional needle wash method. The clotting method avoids diluting FNA samples in liquid media and maximizes the collection of cellular material by holding the aspirate tightly in a blood clot

BACKGROUND: 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). CASE PRESENTATION: 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. CONCLUSION: 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. Diagn. Cytopathol. 2016. (c) 2016 Wiley Periodicals, Inc.

Introduction: Ultrasound guided FNA is important in guiding management of thyroid nodules. Complications are usually limited to localized discomfort, bruising, or minor hematomas. At our institution, cytopathologists perform 600 - 900 ultrasound guided thyroid FNAs yearly. Acute transient thyroid swelling is a rare complication. A diffuse swelling of the entire thyroid occurs after a biopsy with a characteristic "cracked appearance" on ultrasound imaging. Cytopathologists and radiologists need to recognize this phenomenon and terminate the procedure. Materials and Methods: We conducted a retrospective review of our pathology and radiology database from 2004 -2015 for documented transient thyroid swelling. We reviewed patient demographic information, thyroid antibody and function studies, allergies/ medical history, and pathology diagnosis (Table 1). Results: We identified 7 cases of transient diffuse swelling of the thyroid from 6,175 thyroid FNAs. In all cases, the thyroid architecture becomes obscured by diffuse enlargement of the thyroid with an internal "cracked appearance" without skin swelling or hematoma (Figure 1). Imaging shows two to three times increase in overall thyroid volume. Patients usually reported acute pain that resolved shortly after the procedure was ceased and ice pack was applied. Post-procedural observation showed resolution of swelling. Patients had no known latex allergy or prior adverse reactions to needles. In most cases, the patients tolerated initial FNA without complications. One patient had a repeat FNA with Benadryl premedication without adverse complications but it is unclear whether there was a preventative effect. Conclusion: This benign, transient reaction should be distinguished from severe complications such as anaphylaxis and hemorrhage. We hypothesize that this event is attributable to intra-thyroidal edema since no discrete hematoma is seen on imaging. Pre- and post-procedural ultrasound imaging is essential for detecting change in thyroid architecture. Recognition of this rare event is crucial when performing ultrasound guided thyroid FNA. (Figure Presented)

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.

STUDY DESIGN.: Histological growth plate analysis. OBJECTIVE.: To evaluate the histological effects on vertebral growth plates following corrective mechanical tethering in the porcine scoliosis model. SUMMARY OF BACKGROUND DATA.: Theoretically, growth modulation allows progressive vertebral correction in the setting of scoliosis (Hueter-Volkmann principle). METHODS.: This IACUC-approved study divided 9 immature Yorkshire pigs into 2 groups: deforming tether release (TR, n = 4) group and anterior corrective (AC, n = 5) tether group. Once 50 degrees coronal Cobb was demonstrated, TR had release of the deforming tether, whereas AC had release of the deforming tether and additional placement of a corrective tether. After 20 weeks of observation, pigs were killed, spines were removed, and apical samples were prepared for histological study. Growth plate analysis included the following histological parameters: proliferative zone height, hypertrophic zone height, and cell heights within the hypertrophic zone. Student t test was used to evaluate differences within and between groups. RESULTS.: No significant differences were found within the release group on the concave versus convex side in terms of proliferative zone height, hypertrophic zone height, and cell heights in the hypertrophic zone. In the anterior correction group, the proliferative zone height was significantly smaller on the concave side than on the convex side (P < 0.01); no significant differences were found in AC on the concave versus convex side in terms of hypertrophic zone height and cell heights in the hypertrophic zone. No significant differences were found in any parameters between TR and AC on either the concave or the convex side. CONCLUSION.: No significant decrease in any of the measured parameters was observed in the anterior correction group compared with the tether release group. These histological findings are consistent with preservation of growth potential.

Introduction: In an established Porcine Scoliosis Model, previous studies reported the impact on apical vertebrae following corrective tethering; the study's aim was to evaluate the effect of a corrective tether on global alignment and on vertebral growth. Methods: At 12 weeks of age, 21 Yorkshire pigs had a surgical induction of scoliosis. When~50degree Cobb angle was observed, animals were placed into one of three groups: scoliosis model (SM, n = 11), in which pigs were euthanized; tether release (TR, n = 5), in which the inducing tether was removed; and anterior correction (AC, n = 5), in which the inducing tether was removed and an anterior corrective tether device was applied. The TR and AC groups were observed for 20 weeks then euthanized. Histological slides of apical growth plates were prepared. Growth plate analysis included proliferative zone height, hypertrophic zone height, and cell heights in the hypertrophic zone. CT-scan reconstructions were used to measure the vertebral shape and the global alignment. Results: CT scan: There was a significant increase in the vertebral height in TR (2.96 cm +/- 0.21) and AC (2.82 cm +/- 0.15) group compared with SM group (2.57 cm +/- 0.20). For AC, the Cobb angle was reduced (AC 21.0degree+/- 10.9degree; TR 49.5degree+/- 6.6degree; SM 46.8degree+/- 10.4degree), the kyphosis was increased, the vertebral cuneiformization was decreased in the three apical vertebrae and the axial rotation between vertebrae was reduced. Histology: No significant difference was observed between the convex and the concave side for the TR group. For the AC group, the proliferative height was significantly smaller in the concave side. Between groups, no significant difference was found. Discussion: This non-fusion technique does not inhibit the growth of the vertebrae. Moreover, a corrective tether permits growth modulation of vertebrae, decreasing their cuneiformization. This correction demonstrates a reduction of the coronal deformity, while also inducing kyphosis and eliminating axial apical rotation

Introduction Fusion-free techniques for surgical treatment of scoliosis in adolescents involve modulation of growth in order to correct the deformation. A porcine model of scoliosis was validated beforehand, together with a three-dimensional correction method using synthetic ligaments. The purpose of this study was to provide histological and 3D verification of the effects of correction on growing cartilage and vertebral morphology. Methods Following ethics committee approval, scoliotic deformation was induced in 21 immature Yorkshire pigs by means of a left posterolateral ligament. Following progression of the scoliosis (Cobb *50degree), 11 pigs were euthanized (SM group), the motor ligament responsible for deformation was cut in 5 pigs (SL group), the motor ligament was cut and a corrective operation was undertaken by insertion of a corrective anterolateral ligament in 5 pigs (CA group). After 20 weeks of observation, pigs in the latter two groups were euthanized. The 3D scan analysis allowed evaluation of growth, vertebral deformation, correction of the curve and intervertebral rotation; histological analysis allowed quantitation of the height of the proliferative and hypertrophic zones and the size of cells within the hypertrophic zone. ANOVA analysis was performed to compare the different study groups. Results The CT scan results showed an increase in vertebral size in the SL and CA groups. In the CA group, the Cobb angle was reduced (CA 35.9degree +/- 7.9degree, SL 47.8degree +/- 1.7degree, SM 53.1degree +/- 9.2degree), while kyphosis was increased (CA 23.4degree +/- 17.5degree, SM -1.5degree +/- 14.6degree), and vertebral wedging was reduced at the apex, as was an intervertebral rotation (compared with SM and SL). In terms of histology, no significant difference was seen in the SL group between the right and left sides. In the CA group, the height of the proliferative zone was significantly smaller on the side of the concavity (left, p<0.01). Between the SL and CA groups, no difference was seen for any of the parameters. Conclusion One regarding question fusion-free correction concerns the risk of arrested growth due to cartilage injury. The results of this histological and CT study showed no significant change in growth potential between the SL and CA groups regarding the study parameters. These data confirm the preservation of growth potential in the two groups of porcine models of scoliosis and validate the corrective method

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