Interobserver Variability in the Assessment of Tumor Budding in pT 3/4 Colon Cancer: Improvement by Supporting Immunohistochemistry?

The prognostic significance of tumor budding in colon cancer is unequivocally documented, and the recommendations of the International Tumor Budding Consensus Conference (ITBCC) are currently the accepted basis for its assessment. Up to now, it is unknown whether the general use of a supporting cytokeratin immunohistochemistry can improve the interobserver variability and prognostic significance. Six investigators with different levels of experience reassessed 229 cases of colon carcinoma (pT3/4, N+/−, M0) with a supporting cytokeratin immunohistochemistry. The results were compared to previous assessments, which have been performed only on H & E. Bd3 was significantly associated with the occurrence of distant metastases according to the assessments of three out of six investigators (p < 0.05). Only one single investigator reached significant results concerning the cancer specific survival (p = 0.01). The pairwise kappa values range between a poor and moderate level of agreement (range 0.17–0.45; median 0.21). In conclusion, the results show no superiority of the use of an additional cytokeratin immunohistochemistry compared to the conventional analysis on sole H & E slides. Therefore, the general supporting use of a cytokeratin immunohistochemical staining seems to be inadvisable in colon cancer in consideration of necessary resources and costs.

Determining if Residual Eosin From Dehydration and Clearing Solutions Has an Effect on Immunohistochemistry

Objectives Immunohistochemistry is a diagnostic stain that gives more specificity in testing for a disease and/or condition of patient tissue. Moore Regional Hospital is on the cusp of the LEAN Principle and currently in the early stages. The histology laboratory encountered a “waiting waste” problem due to two areas of histology sharing a common instrument. It is proposed to create a protocol on the Tissue-Tek Prisma stainer specifically for running down immunohistochemistry slides using the same alcohols and xylenes within the current H&E staining protocol. Research is scarce on whether residual eosin, from the dehydrating and coverslip phase, has an effect on immunohistochemistry morphology. Materials Three trial runs were conducted using a cytokeratin immunohistochemistry control. Each trial had dependent variables of staining times, staining parameters, and the changes of alcohol and xylenes. Cytokeratin is a feasible slide to use considering time stipulations and due to its prominent positivity. The instruments used in this validation were the BenchMark Ultra and the Tissue-Tek automatic stainer. The reagents used in this validation were the DAB chromagen, Hematoxylin (Ventana), Bluing (Ventana), Xylene (Cardinal), and Alcohol (Cardinal). Results Interpretations concluded that residual eosin does not have any direct artifact or undesirable outcomes. However, minor findings were noted on how the depar solutions did affect the visual quality of the cytokeratin. Conclusions Pros and cons were discussed in terms of moving forward with this process and improving the overall quality of the histology laboratory. It was decided that the lab move forward with the process or automatically running immunoslides down in automatic stainer. The overall quality of the slides improved due to the decrease in human variability and there is time added for the IHC tech to complete other tasks.