Ultrasound-guided core biopsy with on-site cytology-immediate diagnosis in pediatric oncology.

BACKGROUND: Accurate and swift tissue diagnosis is extremely important for the timely initiation of treatment in pediatric oncology. In our department, ultrasound-guided core needle biopsy (US-guided CNB) is used for tissue diagnosis. In 2016, we added on-site cytology, allowing for an immediate primary diagnosis. We retrospectively reviewed our performance in terms of safety and accuracy for CNBs and on-site cytology. METHODS: All pediatric biopsies performed in our hospital between February 2016 and December 2020, were included. Patient clinical, procedural and follow-up data were collected. CNB pathology and cytology results were compared to the final pathologic diagnosis. RESULTS: We included 71 patients for which 72 biopsies with on-site touch imprint (TI) cytology were performed; the average latency time to biopsy was 1 day. Altogether, we had 61 tumors, (58 malignant, 3 benign) and 11 other lesions. On-site cytology diagnosed 58 malignant tumors, 3 benign tumors and 11 non-tumor tissues. The cytologist correctly differentiated tumor from inflammation in all cases, and diagnosed the precise tumor type in 57 cases, with an accuracy of 94% for final diagnosis. We had no complications related to the procedure or sedation. CONCLUSION: US-guided CNB with on-site TI cytology for suspected malignancy in the pediatric population is highly available, safe, and accurate, with real-time diagnosis in most cases. This accelerated diagnostic route has a huge impact on patient care.

Primary synovial sarcoma of the mediastinum: a rare tumor diagnosed by endoscopic ultrasound-fine needle biopsy (EUS-FNB)-Cytomorphologic, immunohistochemical, and molecular analysis.

Primary synovial sarcoma is exceedingly rare in the mediastinum. The differential diagnosis of this rare tumor is complex as a wide array of primary and metastatic tumors occur in this site.A definite diagnosis might be challenging even after tissue sampling. Immunohistochemistry can be very helpful and supportive for the diagnosis, but still inadequate in some cases as these tumors can mimic histopathologically other soft tissue tumors. Hence, in some case, an advanced pathological molecular analysis is needed.Endoscopic ultrasound (EUS) is an important diagnostic tool for mediastinal tumors. While EUS-fine needle aspiration (EUS-FNA) samples are usually inadequate for advanced pathological analysis, tissue acquisition by the newer generation of EUS-fine needle biopsy (EUS-FNB) needles might be sufficient.Here, we present the first report on primary mediastinal synovial sarcoma diagnosed by an immunohistochemical and FISH analysis performed on EUS-FNB tissue sample.

Post-translational Regulation of Radioactive Iodine Therapy Response in Papillary Thyroid Carcinoma.

Background: Radioactive iodine (RAI) is the mainstay of treatment for differentiated thyroid carcinoma (DTC). Nevertheless, the mechanism of RAI resistance that occurs in many patients with DTC remains unknown. We aimed to elucidate the role of post-translational regulation of radioiodine uptake. Methods: We analyzed the expression pattern of the ribosomal glycosylphosphatidylinositol transamidase (GPIT) complex in freshly excised tumors from 10 patients with DTC. We used functional RAI uptake assays to assess the role of GPIT in iodine uptake both in vivo and in vitro. The effects of MEK inhibition on the GPIT subunit PIGU and the sodium iodide symporter (NIS) were assessed in three DTC cell lines and in four human DTC biopsies. We used a multivariable logistic regression model to study the role of PIGU in the response to RAI treatment in advanced DTC. All statistical tests were two-sided. Results: Expression profiling of different GPIT complex subunits revealed statistically significantly lower expression of PIGU in papillary carcinomas than in matched normal thyroid tissue (P < .001). Expression of PIGU in the K1 human papillary carcinoma cell line resulted in a robust increase in NIS glycosylation and trafficking to the cell membrane, accompanied by a robust increase in I125 uptake both in vitro (465 200 ± 56 343 vs 1236 ± 156 counts per million, P < .001) and in vivo (128 945 ± 28 556 vs 7963 ± 192 counts per million, P < .001, n = 5 mice per group). Treatment with the MEK inhibitors U0126 and PD302 rescued PIGU expression. Finally, the PIGU expression levels in tumors of 18 patients with recurrent DTC were associated with a biochemical response to RAI treatment (hazard ratio = 8.06, 95% confidence interval = 3.72 to 12.3, P = .001). Conclusions: We showed that downregulation of PIGU in DTC determines NIS function and RAI avidity. This represents a novel mechanism for RAI resistance.

Computerized cytometry and wavelet analysis of follicular lesions for detecting malignancy: A pilot study in thyroid cytology.

BACKGROUND: The cytologic diagnosis of indeterminate lesions of the thyroid involves much uncertainty, and the final diagnosis often requires operative resection. Computerized cytomorphometry and wavelets analysis were examined to evaluate their ability to better discriminate between benign and malignant lesions based on cytology slides. METHODS: Cytologic reports from patients who underwent thyroid operation in a single, tertiary referral center were retrieved. Patients with Bethesda III and IV lesions were divided according to their final histopathology. Cytomorphometry and wavelet analysis were performed on the digitized images of the cytology slides. RESULTS: Cytology slides of 40 patients were analyzed. Seven patients had a histologic diagnosis of follicular malignancy, 13 had follicular adenomas, and 20 had a benign goiter. Computerized cytomorphometry with a combination of descriptors of nuclear size, shape, and texture was able to predict quantitatively adenoma versus malignancy within the indeterminate group with 95% accuracy. An automated wavelets analysis with a neural network algorithm reached an accuracy of 96% in identifying correctly malignant vs. benign lesions based on cytology. CONCLUSION: Computerized analysis of cytology slides seems to be more accurate in defining indeterminate thyroid lesions compared with conventional cytologic analysis, which is based on visual characteristics on cytology as well as the expertise of the cytologist. This pilot study needs to be validated with a greater number of samples. Providing a successful validation, we believe that such methods carry promise for better patient treatment.

Accuracy and Quality Assessment of EUS-FNA: A Single-Center Large Cohort of Biopsies.

Introduction. Thorough quality control (QC) study with systemic monitoring and evaluation is crucial to optimizing the effectiveness of EUS-FNA. Methods. Retrospective analysis was composed of investigating consecutive patient files that underwent EUS-FNA. QC specifically focused on diagnostic accuracy, impacts on preexisting diagnoses, and case management. Results. 268 patient files were evaluated. EUS-FNA cytology helped establish accurate diagnoses in 92.54% (248/268) of patients. Sensitivity, specificity, PPV, NPV, and accuracy were 83%, 100%, 100%, 91.6%, and 94%, respectively. The most common biopsy site was the pancreas (68%). The most accurate location for EUS-FNA was the esophagus, 13/13 (100%), followed by the pancreas (89.6%). EUS-FNA was least informative for abdominal lymph nodes (70.5%). After FNA and followup, eight false negatives for tumors were found (3%), while 7.5% of samples still lacked a definitive diagnosis. Discussion. QC suggests that the diagnostic accuracy of EUS-FNA might be improved further by (1) taking more FNA passes from suspected lesions, (2) optimizing needle selection (3) having an experienced echo-endoscopist available during the learning curve, and (4) having a cytologist present during the procedure. QC also identified remediable reporting errors. In conclusion, QC study is valuable in identifying weaknesses and thereby augmenting the effectiveness of EUS-FNA.

Unusual leptomeningeal dissemination in a child with extracranial metastatic alveolar rhabdomyosarcoma.

The authors describe a 6-year-old boy diagnosed with alveolar rhabdomyosarcoma located in the thigh, with distal metastases to lungs, bones, and bone marrow. A very good partial response to first-line chemotherapy was obtained, but the child developed fatal leptomeningeal dissemination immediately after complete resection of the primary tumor. This case demonstrates the rapidity with which leptomeningeal spread of extracranial metastatic alveolar rhabdomyosarcoma can occur and underscores the importance of diagnostic lumbar puncture and brain radiological investigations at diagnosis, even when the tumors are not in the parameningeal location.