In June and July 2021, the National Society for Histotechnology (NSH) conducted an online survey designed to assess productivity and staffing in the clinical histology laboratory. The Productivity Benchmarking Survey was developed by the NSH Quality Management Committee. The survey of histology professionals provides critical data that may be used to inform staffing decisions and develop a quality management program. To create usable data the findings were segmented by a range of variables including facility type and size, and productivity related to grossing, embedding, microtomy, and ancillary duties. This study draws a connection between perceived operational efficiencies and the presence of a program or process used to assess employees quality performance for grossing, embedding, and microtomy. A followup survey is planned to further understand these particular employee assessment programs or processes.
There are many published methods of decalcifying bone for paraffin histology; however, the current literature lacks details regarding the processing of ovine tissue. Ovine bone tissue presents challenges, as samples are often denser and larger than other comparative animal models, thus increasing decalcification times. Trifluoroacetic Acid (TFAA) has previously been used to decalcify ovine bone samples for histological analysis. Unfortunately, TFAA is a strong acid and often results in loss of cellular detail, especially in the connected soft tissue. This is generally manifested as over staining with eosin, and a decrease in cellular features which impacts overall histological interpretation. It is well known that leaving tissue in acid for long periods degrades cellular detail; therefore, minimizing decalcification time is critical to accurately determine cellular morphology. Six decalcification solutions (8% TFAA, 20% TFAA, 8% formic acid, 20% formic acid, Formical-4, and XLCal, and three temperatures (room temperature, 30°C, 37°C), were examined to determine their effects on cellular detail in ovine vertebrae and humeral heads. These data clearly indicate that 20% formic acid at 30°C yielded better decalcification rates (2.6 d ± 0.9 d) and cellular detail (none to mild changes) for the vertebrae samples, and 20% formic acid at RT yielded the best cellular detail (none to minimal loss) for humerus samples with a moderate amount of time (6.5 d ± 1.7). These results should establish the optimal demineralization procedures for ovine bone used in scientific studies resulting in improved cellular detail while minimizing decalcification times.
Melan-A is one of the most commonly used immunohistochemical assays (IHC) in dermatopathology laboratories to detect the presence and outline the distribution of melanocytes. It is a cytoplasmic stain that detects a melanocyte-specific cytoplasmic protein involved in the formation of stage II melanosomes. Clinically, Melan-A is primarily used to detect and confirm melanocytic tumors although it is also positively expressed in adrenal cortical tumors and sex cord stromal tumors. We found that Melan-A also detected and highlighted Henderson-Patterson bodies of molluscum poxvirus. To determine if other melanocytic markers detect molluscum contagiosum bodies, S-100, HMB-45, MITF, and SOX-10 were also tested. In 15 tested molluscum cases, Melan-A stains were positive in all cases, whereas the other tested melanocytic markers were negative. Our results confirm that Melan-A is very sensitive in detecting molluscum contagiosum bodies and could be clinically useful to supplement the hematoxylin and eosin (H&E) in cases that are very inflamed or only have limited biopsy material.
The objective of this study was to provide optimized processing for examination of rat incisors in nonclinical toxicity studies that enables analysis using immunohistochemistry (IHC). Rat maxillas and mandibles were decalcified in Immunocal, a formic acid decalcifier, and Decal Stat, a hydrochloric acid decalcifier, to evaluate tissue quality when with hematoxylin and eosin (H&E) stain and an IHC. Following necropsy of 10 to 13-week-old male Sprague Dawley rats, tissues were collected, trimmed, fixed in neutral buffered formalin (NBF), and placed into the corresponding decalcifying solution. After a pilot study with multiple timepoints for both decalcifying solutions, times were selected for the definitive study. Incisors in the definitive study were decalcified for 72, 96 or 120 hours in Immunocal and 24 hours in Decal Stat, trimmed, processed, embedded in paraffin, and sectioned. The microtomy process and sections were evaluated by histotechnologists. Sections were stained withH&E or an IHC to detect vimentin. Veterinary pathologists used blinded assessment to evaluate staining and tissue quality. The H&E sections from Immunocal timepoints scored higher based on criteria such as cellular morphology. However, tissue quality decreased at 120 hours with Immunocal but was adequate after 24 hours with Decal Stat. For IHC, moderate to excellent expression of vimentin was observed at timepoints for both decalcifiers. Optimal tissue sectioning and histological quality were achieved on incisor sections decalcified for 96 hours with Immunocal and 24 hours with Decal Stat.
Enhancer of zeste homolog 2 (EZH2) and AT-rich interactive domain 1A (ARID1A) expression in urothelial carcinoma (UC) has not been well studied. ARID1A is a novel tumor suppressor gene coding for a chromatin remodeling protein that is mutated in urinary bladder cancer. The enhancer of zeste homolog 2 (EZH2) is a transcriptional repressor involved in gene silencing. Amplification of EZH2 has been reported in several malignancies. This study analyzed the immunohistochemical expression of EZH2 and ARID1A in 56 cases of UC that included (n = 21) cases of radical cystectomy and (n = 35) cases of transurethral resections of bladder tumor (TURBT) with muscle fibers and immunotherapy with adjuvant intravesical bacillus Calmette-Guerin (BCG). The predicting role of both markers for tumor recurrence and recurrence-free survival (RFS) was also analyzed. High EZH2 marker expression was observed in 75% of cases while 78.6% of cases had low ARID1A marker expression. There was a significant negative correlation between the two markers where high EZH2 and low ARID1A expression was significantly associated with higher tumor grade, stage, presence of muscle invasion, lymph node metastasis, presence of concomitant carcinoma in situ (CIS) and higher incidence of recurrence with shorter RFS rate. It was concluded that EZH2 and ARID1A play a role in tumor carcinogenesis and differentiation and could be considered as independent prognostic factors in UC and for use as a potential therapeutic target.
Falloposcopy is the endoscopic examination of the fallopian tubes, which are challenging to access due to their deep body location, small opening from the uterus, and lumen filled with plicae. We and others have developed endoscopes that are inserted through the uterus guided by a hysteroscope into the tubal ostium. To better understand how to utilize these endoscopes either as standalone devices or in concert with everting delivery balloons, a preliminary study of anatomy and mechanical behavior was performed ex vivo on porcine and human fallopian tubes. Segments of fallopian tubes from the isthmus, ampulla and infundibulum were inflated with saline either to bursting or held at sub-burst pressures with saline or a saline-filled balloon. Formalin fixed, paraffin embedded tissue sections stained with Masson's trichrome were examined for damage to the mucosa and muscularis. Porcine fallopian tubes tolerated saline pressurization at 15 psi for 1 minute without morphological damage. Balloon inflation to 15 psi caused no apparent damage to the muscle layer or rupture of the fallopian tube, but balloon movement within the tube can denude the mucosal epithelial layer. Human fallopian tubes averaged higher burst pressure values than porcine tubes. Under pressurization, the external tube diameter expanded by minimal to moderate amounts. Human and porcine tissues were similar in histological appearance. These studies suggest that moderate pressurization is acceptable but will not appreciably expand the fallopian tube diameter. The results also indicate that pigs are a reasonable model to study damage from falloscopy as seen in human tissue.