Acute myeloid leukemia with myelodysplasia-related changes with erythroid differentiation involving pleural fluid: a case report and brief cytopathologic review.

The vast majority of malignant pleural effusions are caused by metastatic adenocarcinoma, most frequently from breast or lung primaries. However, a minority of cases show evidence of involvement by a hematopoietic neoplasm such as lymphoma or leukemia. We report a rare case of a 54-year-old male with a prior diagnosis of acute myeloid leukemia with myelodysplastic-related changes (AML-MDS) with erythroid differentiation having new onset pleural effusions containing leukemic blasts. The pleural specimen was comprised of blast forms having large round nuclei with finely dispersed chromatin and prominent nucleoli, with scattered binucleate forms. The blasts expressed CD45 and CD34 and were negative for epithelial and mesothelial markers. Previous bone marrow biopsies had shown that the blasts exhibited strong staining for hemoglobin and lacked expression of Factor VIII and myeloperoxidase, consistent with erythroid differentiation. Although rare, this case indicates the need for consideration of unusual disease states presenting within a pleural fluid and highlights the differential diagnosis and immunohistochemical profile of AMLs with erythroid differentiation.

High-grade prostatic sarcoma seen in a catheterized urine specimen: case report and differential diagnosis.

Urine cytology has been effectively used in the diagnosis and management of epithelial bladder tumors, particularly high-grade urothelial carcinoma. Indeed it is the gold standard for bladder cancer screening. Although urothelial carcinoma is the most frequently identified bladder tumor by urine cytology, metastatic carcinomas from the kidney, colon, and a variety of other regional organs have been detected. Stromal lesions such as inflammatory myofibroblastic tumor, gastrointestinal stromal tumor, and leiomyosarcoma are other much rarer entities occurring within the bladder. Few to no case reports exist documenting their identification within urine cytology specimens. Herein we report the detection of a high-grade prostatic sarcoma within a catheterized urine specimen of a young male having a diffusely enlarged prostate. The specimen consisted of numerous fragments of relatively uniform spindle cells having ovoid nuclei with rounded ends and finely dispersed chromatin. Cytoplasmic borders were indistinct. No mitoses or significant atypia was present. The background consisted of numerous red blood cells, cellular debris, and a few clusters of unremarkable urothelial cells. Followup surgical biopsy of the patient's prostate revealed a high-grade spindle-cell sarcoma. Further immunohistochemical and molecular delineation of the tumor was not informative for a more definitive diagnosis. Although rare, sarcomas and other mesenchymal tumors involving the bladder are unique entities with a broad differential diagnosis.

Cytology of fine-needle aspiration of inflammatory myofibroblastic tumor.

Inflammatory Myofibroblastic Tumor (IMT) is a rare spindle cell neoplasm with a relatively indolent course. Its morphology may be confused with both reactive processes and/or malignant neoplasms on FNA specimens. Herein we discuss the cytologic features and IHC studies of IMT. The archives of the Department of Pathology at the Johns Hopkins Hospital were searched for IMT. A total of 257 cases were identified over a period of 11 years. Among them, 20 cases had cytology material. The patients' ages ranged from 7 to 81 years old with a median age of 54 years. The locations of the tumor in descending order were: liver (9/20, 45%), lung (8/20, 40%), abdomen (1/20, 5%), pelvis (1/20, 5%), and kidney (1/20, 5%). On FNA, the majority of tumors consisted of bland spindle cells with oval nuclei and small prominent nucleoli in a background of lymphocytes and plasma cells. Focal cytological atypia and "ganglion-like" cells were identified in 7 cases, likely related to the risk of metastases and malignant transformation. The lesional cells expressed ALK (8/17, 47.1%) and actin (10/10, 100%), but with variable expression of cytokeratin. Ki-67 showed low proliferative indices. ALK gene rearrangement was detected by FISH in three out of three cases and correlated with ALK protein expression by IHC. The cytologic diagnosis of IMT is challenging. When encountering a spindle cell lesion with prominent inflammatory component, a high index of suspicion in combination with the use of ancillary studies increases the diagnostic yield of IMT.

Cytology of endobronchial ultrasound-guided transbronchial needle aspiration versus conventional transbronchial needle aspiration.

BACKGROUND: Conventional endoscopic transbronchial needle aspiration (TBNA) is a common procedure used to obtain samples for diagnosing and staging lung lesions. Recently, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has been developed and increasingly used by clinicians. Clinical data suggest that EBUS-TBNA has higher sensitivity and specificity than conventional TBNA in staging lung cancers. In this study, the authors have investigated the cytological features and compared the diagnostic yield of these procedures in lung cancer patients. METHODS: A computer search of the cytopathology archives at The Johns Hopkins Hospital revealed 188 EBUS-TBNA cases (308 lymph nodes; 47 lung lesions) and 74 TBNA cases (106 lymph nodes; 44 lung lesions) over a 28-month period. All cytological material was correlated with available corresponding surgical material. RESULTS: The most frequently sampled lymph nodes were stations 4R and 7 in both TBNA and EBUS-TBNA; in addition, the EBUS-TBNA showed a wide range of lymph node sampling. EBUS-TBNA had a significantly lower nondiagnostic rate (8.7%) compared with TBNA (28.3%, P < .05) in staging lung cancers. In lymph node sampling, the sensitivity and specificity were 54.5% and 100% in the TBNA group and 85.2% and 100% in the EBUS-TBNA group. In lung specimens, the nondiagnostic rates of TBNA and EBUS-TBNA were 6.8% and 4.3%, respectively (P > .05), and the sensitivity and specificity were 78.9% and 100% in the TBNA group; and 89.5% and 100% in the EBUS-TBNA group. CONCLUSIONS: Findings indicated that EBUS-FNA cytology is an optimal modality for diagnosing and staging in lung cancer patients, in comparison to conventional TBNA.

Cytologic diagnosis and differential diagnosis of lung carcinoid tumors a retrospective study of 63 Cases with histologic correlation.

BACKGROUND: Neuroendocrine (NE) neoplasms of the lung are a spectrum of tumors including typicalcarcinoid (TC), atypical carcinoid tumor (ACT), small cell lung carcinoma (SCLC), and large cell NEcarcinoma (LCNEC). Given the overlapping features within these tumors, misclassification is a known risk, with significant treatment consequences. METHODS: A search of the pathology archives from The Johns Hopkins Hospital yielded 390 cases of TC diagnosed over 20 years. Sixty-three cytology cases with corresponding surgical material were identified. The cytology specimens were comprised of 49 cases of lung fine-needle aspiriation specimens and 14 cases of lung brushings/washings. RESULTS: Among 63 paired cases, 32 cases (51%) demonstrated concordant and 31 cases (49%) demonstrated discordant diagnoses. Among discordant cases, the most notable findings included overdiagnosis of TC as SCLC (4 cases; 6%), ACT (4 cases; 6%), and poorly differentiated carcinoma with NE features (5 cases; 8%) as well as misdiagnosis of other lesions as TC (4 cases; 6%) on cytology. CONCLUSIONS: The significant morphologic factors for distinguishing low-grade TC from ACT, SCLC, or carcinoma remain the critical evaluation of nuclear features, chromatin patterns, and assessment of nucleoli. Nuclear molding and crowding are not discernible features because they may be found on smears with increased cellularity. Crush artifact can occur in both low-grade and high-grade NE neoplasms and may cause a misinterpretation of SCLC. Other artifacts resulting from delayed fixation or poor processing and sampling error are potential causes of incorrect interpretations. Ki-67 staining may be useful in difficult cases.

Metastatic retinoblastoma presenting as a left shoulder soft tissue mass: FNA findings and review of the literature.

Retinoblastoma is a relatively rare malignant pediatric tumor accounting for approximately 3% of childhood cancers and 1% of all cancer deaths in children under 15 years of age. During the clinical course of the disease, a metastasis usually occurs within the first year of diagnosis and is seen in 2% of retinoblastoma patients. Metastases to the intracranial region are common and account for approximately 50% of the metastatic cases. Metastasis to the soft tissue is very rare. Herein, we report a case of metastatic retinoblastoma presenting as a left shoulder soft tissue mass in a 14-year-old female with a 14-year history of familial bilateral retinoblastoma status post radiation therapy. In our case, the FNA cytology shows some features of the small round blue cell tumor group with inconspicuous Flexner-Wintersteiner or Homer-Right rosette formation. The unusual clinical presentation and morphology give rise to a diagnostic dilemma, with the differential diagnosis centering on the small round blue cell tumors such as lymphoma, rhabdomyosarcoma, nephroblastoma (Wilms' tumor), Ewing's sarcoma/PNET, and desmoplastic small round cell tumor. It also prompts concern for the development of a second primary tumor. The purpose of our study is to discuss the FNA cytology of metastatic retinoblastoma, its differential diagnoses, and the utility of immunohistochemistry. An accurate diagnosis is imperative due to the differences in prognosis and treatment implications for the various diseases.

Cytologic diagnosis and differential diagnosis of lung carcinoid tumors a retrospective study of 63 cases with histologic correlation.

BACKGROUND:: Neuroendocrine (NE) neoplasms of the lung are a spectrum of tumors including typical carcinoid (TC), atypical carcinoid tumor (ACT), small cell lung carcinoma (SCLC), and large cell NE carcinoma (LCNEC). Given the overlapping features within these tumors, misclassification is a known risk, with significant treatment consequences. METHODS:: A search of the pathology archives from The Johns Hopkins Hospital yielded 390 cases of TC diagnosed over 20 years. Sixty-three cytology cases with corresponding surgical material were identified. The cytology specimens were comprised of 49 cases of lung fine-needle aspiriation specimens and 14 cases of lung brushings/washings. RESULTS:: Among 63 paired cases, 32 cases (51%) demonstrated concordant and 31 cases (49%) demonstrated discordant diagnoses. Among discordant cases, the most notable findings included overdiagnosis of TC as SCLC (4 cases; 6%), ACT (4 cases; 6%), and poorly differentiated carcinoma with NE features (5 cases; 8%) as well as misdiagnosis of other lesions as TC (4 cases; 6%) on cytology. CONCLUSIONS:: The significant morphologic factors for distinguishing low-grade TC from ACT, SCLC, or carcinoma remain the critical evaluation of nuclear features, chromatin patterns, and assessment of nucleoli. Nuclear molding and crowding are not discernible features because they may be found on smears with increased cellularity. Crush artifact can occur in both low-grade and high-grade NE neoplasms and may cause a misinterpretation of SCLC. Other artifacts resulting from delayed fixation or poor processing and sampling error are potential causes of incorrect interpretations. Ki-67 staining may be useful in difficult cases. Cancer (Cancer Cytopathol) 2010. © 2010 American Cancer Society.

Metastatic signet ring cell carcinoma presenting as a thyroid nodule: report of a case with fine-needle aspiration cytology.

Metastatic carcinomas to the thyroid are quite rare in daily cytology practice. However, when present they may produce a diagnostic dilemma, particularly when they share some morphologic similarities with primary thyroid lesions and when occurring in patients with occult malignant history. Herein, we report a case of metastatic gastric signet ring cell carcinoma to the thyroid. Our patient presented with an isolated right thyroid nodule, which was clinically considered to be a primary thyroid neoplasm. Fine-needle aspiration (FNA) cytology of the nodule revealed a cellular specimen with cohesive fragments and scattered individual neoplastic cells. The neoplastic cells had enlarged nuclei, fine chromatin, and inconspicuous nucleoli. Nuclear crowding, molding, and grooving were prominent. Intranuclear inclusion-like clearance was identified. Some tumor cells also had eccentric nuclei, creating a signet ring cell appearance. The colloid was scant. These cytological features may be seen in cases of papillary thyroid carcinoma or signet ring cell follicular adenoma; however, the presence of the signet ring cells is unusual in primary thyroid lesions and raises the possibility of a metastatic lesion to the thyroid. In our case, the tumor cells were positive for AE1/AE3, mucicarmine, and periodic acid-Schiff, but negative for thyroglobulin and thyroid transcription factor-1. The patient was also found to have a 3.7-cm mass in the distal esophagus/proximal stomach. Biopsy of this mass showed an invasive signet ring cell carcinoma. The purpose of our study is to discuss the cytological features and the differential diagnosis of this unusual thyroid FNA case.