Detection of non-haematolymphoid malignancies in bronchoalveolar lavages-A cancer centre's 10 year experience.

INTRODUCTION: Fibreoptic bronchoscopy with bronchoalveolar lavage (FOB-BAL) is often performed in immunocompromised and cancer patients to investigate possible infectious and non-infectious causes of clinical and radiological respiratory abnormalities. Knowledge of the incidence and distribution of non-haematolymphoid malignancies (NHLM) detected by FOB-BAL in this population is limited. METHOD: Our pathology electronic database was searched from July 1, 2008 to June 30, 2018 for BAL specimens with diagnoses of "malignant" and a review of the pathology report and electronic medical record was performed. Statistical analyses were performed to determine the incidence, distribution of NHLM, and demographics of patients in these BALs. RESULTS: A total of 209 (1.92%) out of 11 035 BAL cases were reported in the "malignant" category. After exclusion of 22 cases with haematolymphoid malignancies, 187 cases were included in this study. The average patient age was 58 years (ranging from 9 to 83 years). The most common NHLM identified were from lung/thoracic primaries (n = 103; 55.1%) with adenocarcinoma being the most common type of lung primary (n = 91; 88%). Other tumours detected included carcinomas from breast (n = 34; 18.2%), gastrointestinal tract (n = 17; 9.1%), genitourinary tract (n = 13; 7%), Müllerian origin (n = 8; 4.3%), and head and neck (n = 6; 3.2%). Rarer NHLM encompassed 3.2% of BALs (n = 6). CONCLUSION: FOB-BAL is a useful tool for evaluating various pulmonary abnormalities in our cancer institute's patient population and a valuable method for detecting NHLM, which is critical to guide appropriate subsequent therapies.

Case Report of Myeloid Sarcoma Masquerading as In-Transit Metastasis at a Previous Melanoma Site: Avoiding a Diagnostic Pitfall.

Myeloid sarcoma is a rare extramedullary hematologic malignancy. Accurate and timely diagnosis may be challenging because myeloid sarcoma is known to mimic solid tumors, including hepatobiliary, nasopharyngeal, and breast carcinomas. We report a case of myeloid sarcoma that developed in the primary tumor lymphatic drainage field of a previously treated intermediate-thickness cutaneous melanoma, clinically and radiographically mimicking an in-transit metastasis, in a patient with myelodysplastic syndrome. The diagnosis of myeloid sarcoma was achieved after surgical excision of the mass and pathological examination that included extensive immunohistochemical studies. Awareness of such an unusual clinical presentation can help reduce diagnostic delay and ensure that adequate tissue is obtained for pathological examination and ancillary studies that are critical for accurate diagnosis and appropriate patient management.

Evaluating Mismatch Repair/Microsatellite Instability Status Using Cytology Effusion Specimens to Determine Eligibility for Immunotherapy.

CONTEXT.­: The approval of pembrolizumab for treatment of patients with microsatellite instability-high (MSI-H) or mismatch repair-deficient (dMMR) advanced cancers has led to increased requests for MSI and/or MMR immunoperoxidase (IPOX) testing. Diagnoses for patients with advanced-stage cancer are frequently made from cytology specimens. OBJECTIVE.­: To investigate the feasibility of using cell block (CB) preparations of effusions for MMR IPOX evaluation. DESIGN.­: Surgical pathology cases of colorectal and endometrial carcinomas with known MMR/MSI status and matched effusions with available CBs were identified. Cell block sections were evaluated for adequacy and stained with MMR IPOX (MSH2, MSH6, MLH1, and PMS2). The CBs were reviewed, the number of tumor cells quantified, and MMR IPOX was interpreted as retained, lost, suboptimal, or noncontributory. RESULTS.­: We identified 748 cases with MMR/MSI testing on surgical specimens having matched effusions. Of these, 131 cases (17.5%) had an available CB and 53 were deemed adequate for MMR IPOX staining. MMR IPOX results between effusion CBs and surgical pathology specimens were concordant in 45 of 53 (85%), inconclusive in 6 of 53 (11%), and discordant in 2 of 53 (4%) cases. CONCLUSIONS.­: There was high concordance of MMR IPOX testing between cytologic and surgical specimens, with no false-positive and 2 false-negative CB results. Limited tumor cells, staining in cells indefinite as tumor, tumor staining heterogeneity, and lack of internal control staining were problematic in some cases. Our findings indicate that cytologic effusion specimens may be suitable substrates for MMR IPOX biomarker testing; however, inconclusive cases need to be interpreted with caution.

The value of a tiered cytology diagnostic reporting system in assessing the risk of malignancy in indeterminate serous effusions.

BACKGROUND: The International System for Reporting Serous Fluid Cytopathology was recently proposed as a tiered structure to provide consistent reporting terminology for serous effusions. Because of the variation in reporting practices for indeterminate serous effusions, namely, the atypia of undetermined significance (AUS) and suspicious for malignancy (SFM) groups, the authors retrospectively reviewed cases in these 2 categories at their institution and determined the associated risk of malignancy (ROM). METHODS: Pleural, peritoneal, and pericardial effusions that were reported as AUS or SFM over a 1-year period were reviewed, and their associated ROMs were calculated based on confirmation of malignancy by previous and/or subsequent fluid and/or tissue biopsy specimens from the same general location. RESULTS: In total, 145 AUS and 98 SFM serous effusion cases were identified. The AUS category was used when the cells in question lacked the requisite quantitative (cell number) and/or qualitative (morphologic) features for a definitive diagnosis. Immunohistochemistry (IHC) or flow cytometry (FCM) was available in 15% of cases (n = 22) with inconclusive results. The ROM based on 69 cases with available follow-up results was 39%. In contrast, the SFM category demonstrated cells that were morphologically suspicious for malignancy but sparse, precluding IHC or FCM (n = 63; 64%) or yielding inconclusive results (n = 35; 36%). The ROM in the SFM category, based on follow-up results of 61 cases, was 64%. CONCLUSIONS: The ROM for SFM was significantly higher than that for AUS (P < .01), supporting separate diagnostic categories for these 2 groups.

A common complication of myelofibrosis presenting as a rare finding in cerebrospinal fluid cytology.

Herein, we present a rare case of intracranial extramedullary hematopoiesis (EMH) diagnosed by cerebrospinal fluid (CSF) cytology and describe the clinical presentation, radiologic, and pathologic findings. A 65 year-old man with a history of progressing primary myelofibrosis was admitted for headaches and right facial numbness. A brain MRI revealed focal abnormalities that were suspicious for leptomeningeal involvement of acute leukemia. Cytologic examination of CSF demonstrated a hypercellular specimen composed of hematopoietic cells including few blasts, as well as maturing red blood cells and granulocytic cells. The integration of morphologic findings, peripheral blood and bone marrow counts, as well as flow cytometric analysis of CSF and bone marrow, excluded leptomeningeal involvement by leukemic blasts and helped establish the diagnosis of intracranial EMH. Inclusion of EMH in the differential diagnosis of intracranial pathology in patients with known conditions predisposing them to EMH is important because recognizing this rare event has implications for treatment and prognosis.

Non-seminomatous germ cell tumor with bone metastasis only at diagnosis: A rare clinical presentation.

Bone metastasis of non-seminomatous germ cell tumors (NSGCT) of the testes is a rare event and even more uncommon at initial presentation. Generally, bone lesions are discovered in the presence of concurrent retroperitoneal lymph node or visceral disease. However, in this case, a 37 years old male complaining of a growing testicular mass was found to have isolated bone metastasis with associated caudaequina syndrome without apparent abnormal findings on initial computed tomography (CT) scans. Continued neurologic symptoms prompted further evaluation with magnetic resonance imaging (MRI), which demonstrated multiple sites of bone metastasis without evidence of retroperitoneal lymph node or visceral organ involvement. This case represents a rare clinical presentation and disease manifestation of NSGCT.

Pulmonary artery intimal sarcoma diagnosed using endobronchial ultrasound-guided transbronchial needle aspiration.

Intimal sarcoma of the pulmonary artery is a rare intraluminal malignant neoplasm that has an aggressive biological behavior, and early diagnosis may improve patient outcome. We describe a case of pulmonary artery intimal sarcoma diagnosed on cytologic material obtained by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) biopsy with rapid on-site evaluation (ROSE). The aspirate showed loosely cohesive clusters of pleomorphic malignant spindled and epithelioid cells. An immunostain panel did not demonstrate any definitive mesenchymal or epithelial differentiation. The tumor's intraluminal origin was supported by radiographic imaging studies. Subsequently, the patient received preoperative chemotherapy and underwent tumor resection with reconstruction. This report describes the cytomorphologic features of this rare intravascular tumor and demonstrates how EBUS-TBNA with ROSE was instrumental in obtaining optimal cytologic sampling for ancillary studies, thus expediting the management.

Fine-needle aspiration diagnosis of lymphomas with signet ring cell features: potential pitfalls and solutions.

BACKGROUND: Lymphoma with signet ring cell features (LSF) is a rare morphologic variant of non-Hodgkin lymphoma. Although it has been well documented in the surgical pathology literature, to the best of the authors's knowledge, the features of LSF in fine-needle aspiration (FNA) samples have rarely been reported. An accurate cytologic diagnosis of LSF is of important therapeutic significance. METHODS: The authors retrospectively reviewed 7 FNA cases of LSF for cytologic features, ancillary studies, corresponding histologic findings, and the patients' clinical and radiologic information to illustrate the diagnostic clues and potential pitfalls. RESULTS: The final diagnoses, based on a multidisciplinary approach, were follicular lymphoma (5 patients), large B-cell lymphoma of follicular center cell origin (1 patient), and low-grade B-cell lymphoma with plasmacytoid features (1 patient). FNAs were obtained from both lymph node and extranodal sites. Common cytologic features included various percentages of signet ring cells in a background of nonvacuolated lymphomatous cells, lymphoglandular bodies, and cytoplasmic rings. The majority of signet ring cells contained a single, large, clear intracytoplasmic vacuole that pushed the nucleus laterally whereas fewer cells contained ≥ 2 vacuoles that indented the nucleus into a scalloped or stellate configuration. These cells resemble, to some degree, other lesions with signet ring cell features. One of the diagnostic clues of LSF was the similarity in nuclear details between signet ring cells and surrounding nonvacuolated lymphoid cells. CONCLUSIONS: Familiarity with cytologic features, correlation with clinical/radiologic information, and ancillary studies are important for an accurate diagnosis of LSF and for distinguishing it from other lesions with signet ring cell features in FNA samples.

Fine-needle aspiration cytology of sclerosing adenosis of the breast: a retrospective review of cytologic features in conjunction with corresponding histologic features and radiologic findings.

We retrospectively reviewed 25 fine-needle aspiration cases of sclerosing adenosis of the breast in conjunction with histologic features of the paired core-needle biopsy and radiologic findings. The original cytologic diagnoses were benign (n = 19), focally atypical (n = 3), and suspicious for carcinoma (n = 3). The frequent features, although not specific, were low-to-moderate cellularity, bland epithelial cells that focally formed cohesive groups/tubules or occasionally discohesive clusters or individual cells, and fragments of dense fibrous stroma. Some tubules had an angulated configuration. Myoepithelial cells were present in all cases but were scant or absent in small epithelial groups. These cytologic features closely reflected the histologic appearances (ie, compressed and attenuated tubules and sclerotic stroma), but may cause overinterpretation on cytologic smears, especially when angulated tubules, discohesive or individual epithelial cells, scanty myoepithelial cells, and nuclear atypia are noted concurrently. Familiarity with its cytologic features may prevent false-positive diagnosis. Histologic confirmation is recommended for difficult cases.