Diagnostic Cytopathology最新文献

Background: Cytologic examination of peritoneal fluid (PTFL) often represents the first and only pathologic specimen available to guide management of gynecologic malignancies (GMs). This study examines the cytohistologic correlation between histotyping of GM in PTFL and its corresponding surgical specimen (SS).

Methods: The study retrospectively identified positive PTFL with a GM between 2017 and 2022. Cytologic specimens (CSs) that were obtained after or concurrently with its diagnostic SS (biopsy/resection) were excluded. Root cause analysis of discordant cases was performed by reviewing morphology, specimen characteristics, and immunophenotype of CS.

Results: GM affected 55.8% (502/899) of malignant PTFL, of which 15.7% (79)/22.3% (112) was the only/initial diagnostic sample, respectively. Compared to SS, when a subtype was rendered on CS (91.9%), the concordance rate is 91.2% (almost perfect agreement, K = 0.842). Factors contributing to incorrect/inadequate subtyping include specimen limitations (low volume and/or cellularity), cytopathologist preference, and insufficient immunophenotyping. In seven patients (1.4%), the CS was able to render a more definitive diagnosis than its preceding nondiagnostic SS due to the paucity of lesional cells.

Conclusion: When compared to SS, histotyping of GM in PTFL is reliable and, at times, can be more definitive than its surgical counterpart. In some cases, subtyping is limited by extrinsic factors (i.e., specimen limitations). In other cases, the responsible cytopathologist prefers not to subtype despite supportive morphologic and immunohistochemical features. This highlights an opportunity for improvement in the diagnosis/subtyping of GM in PTFL, which may be the initial or only diagnostic specimen prior to patient treatment.

Hobnail papillary thyroid carcinoma (HNPTC) is an unusual and aggressive variant of PTC. Malignant pleural effusion secondary to thyroid carcinoma is a rare event reported in less than 1% of cases. Herein we present a case of metastatic HNPTC initially diagnosed by pleural effusion cytology, with a very poor outcome. A 42-year-old male with no previous cancer history, presented with an anterior neck mass growing for the past year. A computed tomography (CT) scan revealed a large complex cystic lesion with mass effect on the anterior thyroid gland, along with multiple neck and mediastinal necrotic lymph nodes, suspicion for metastasis. CT of the thorax showed lung nodules and a large left pleural effusion. Fluid was drained and sent for cytologic examination which revealed malignant cells predominantly in a micropapillary pattern with apically placed, bulged, "hobnail-like" appearance; intranuclear pseudo-inclusions or chromatin clearing was not seen. Based on cytomorphologic findings and immunohistochemical results (CK7 and PAX-8 positive; TTF-1, Napsin-A, and mesothelial markers negative), final diagnosis of HNPTC metastatic to pleural fluid was made. Fine-needle aspiration of neck mass showed similar cytomorphologic findings, confirming a thyroid origin. However, the patient experienced complications, rapid deterioration and died 6 months after diagnosis. The intersection of clinical-radiologic findings, cytology, and immunohistochemistry guided the identification of this rare variant of PTC as the origin of the malignant pleural effusion. We believe this case provides a valuable insight into the complexities involved in the diagnosis of thyroid carcinoma and emphasizes the significance of proper identification of rare variants.

Bile duct brush cytology is a widely used and essential method for evaluating biliary tract lesions, although it remains challenging for pathologists. Liquid-based preparations provide a better vision of morphology and enable the preparation of cell blocks, thereby enhancing reliability. However, the establishment of reproducible interpretation criteria and utilization of cell blocks remain limited. This study aimed to investigate the morphological features of liquid-based cytology using objective and reproducible criteria, incorporating histological findings to identify diagnostic features. In total, 151 cases were selected and 42 morphologic criteria were evaluated within representative clusters. Notably, 14 features, including conventional cytologic features, significantly differed between the benign and malignant groups. Malignant cell clusters were more likely to be irregularly shaped and have larger nuclear sizes, increased nuclear pleomorphism, a non-euchromatic chromatin pattern, and a higher nucleus-to-cytoplasm (N/C) ratio. Multinucleation and nuclear molding were observed exclusively in malignant cases. The presence of inflammatory cells did not differ significantly between benign and malignant cases. An increased N/C ratio was observed in the cell blocks and the architectural information aided in diagnosis. The application of cell blocks may be beneficial, emphasizing the significance of nuclear pleomorphism. We also categorized features by analyzing the sensitivity, specificity, and importance of various features. In summary, our study reaffirms the importance of conventional cytomorphologic features in liquid-based preparations of bile duct cytology and suggests a diagnostic approach with more objective morphologic criteria, highlighting the utility of cell blocks.

Solitary plasmacytomas are localized single tumors of monoclonal plasma cells that occur in two variants: solitary plasmacytoma of bone and extraosseous plasmacytoma. Solitary plasmacytoma of bone accounts for only 1%-2% of plasma cell lesions, and extraosseous plasmacytoma is also approximately 1%. These are both very uncommon at the skull base. We report two cases of plasmacytic neoplasms at the skull base where the differential diagnosis included pituitary adenoma when the tumor was sellar/suprasellar, or other bone-related tumors such as chordoma/chondrosarcoma when clivus/sphenoid bones were involved. Intraoperative diagnosis was facilitated by the use of cytologic preparations.

Background: Phaeohyphomycosis is a very rare fungal infection, which is one of more usual complications in immunocompromised and/or traumatic patients, has never been reported especially in a cytological field. We describe a first case of subcutaneous phaeohyphomycosis caused by Exophiala xenobiotica (E. xenobiotica) in a poorly controlled diabetic patient, and in which a correct cytological diagnosis of phaeohyphomycosis was possible to conclude.

Case presentation: The diabetic obese patient was a 60's-year-old male with a chief complaint of subcutaneous cyst-like nodule on the left knee. The Papanicolaou staining on aspiration cytology from this central fluid contained a substantial number of characteristically brown hyphae with dichotomous branching conidiophores and annelloconidia formation, in the necrotic and inflammatory backgrounds. Culture on potato dextrose agar showed many slow-growing yeast-like colonies particularly in an olivaceous gray to black colored fashion. Furthermore, sequencing data for the rRNA internal transcribed spacer (ITS) regions confirmed phaeohyphomycosis caused by E. xenobiotica infection. Histologically, the resected subcutaneous nodule was diagnosed as necrotizing epithelioid granulomas with central abscess formation, admixed with a large number of dichotomous branching fungal organisms with conidia, reminiscent of Aspergillus. However, Fontana-Masson staining readily identified the melanin pigments in these fungal hyphae.

Conclusion: In this subcutaneous cyst-like case of immunocompromised patient, it is critical to consider the possibility of subcutaneous phaeohyphomycosis. The conventional methodology of Papanicolaou staining on cytology specimen can recognize characteristically typical dichotomous branching and brown-pigmented fungi, potentially guiding us to the correct and quick diagnosis.

The measurement of Calcitonin (Ctn) in fine-needle aspiration (FNA) washout fluids (FNA-Ctn) has demonstrated excellent sensitivity, significantly higher than FNA cytology, in detecting medullary thyroid carcinoma (MTC). However, the absence of a fixed cutoff value for FNA-Ctn poses a limitation. This study aimed to investigate whether the sensitivity of FNA-Ctn in detecting MTC varies with different cutoffs reported in the literature. A single-centre series of MTCs was retrospectively reviewed. The preoperative FNA-Ctn levels were re-evaluated using various thresholds previously reported in the literature, and the corresponding FNA-Ctn sensitivities were compared. Twenty-one MTCs were included (69% women; median age 59 years; median serum Ctn value 86 pg/mL; median MTC major diameter 10 mm). The median FNA-Ctn value was 2000 pg/mL (interquartile range 49-250). MTCs nodules were assessed at high risk (ACR TI-RADS 5) in 50% of cases, while 47.6% were cytologically malignant. Additionally, 42.9% of cases were assessed as stage III according to Union for International Cancer Control staging system (UICC). Serum Ctn was significantly lower in stage I (p = 0.04). FNA-Ctn was positively correlated with serum Ctn (Rho = 0.45; p = 0.04), while ACR TI-RADS assessment with MTC stage (Rho = 0.69; p = 0.003). FNA-Ctn sensitivity ranged from 95% to 100% based on the previously proposed FNA-Ctn cutoffs. The high sensitivity of FNA-Ctn in detecting MTC did not significantly differ when applying the previously proposed cutoffs. Given the absence of a universally applicable FNA-Ctn decisional threshold, institutions should establish their own diagnostic cutoffs. Future guidelines should incorporate these concepts to enhance clinical decision-making and patient outcomes.