Application of tissue-marking ink to prostate biopsy specimens

BACKGROUND. When sextant prostate biopsy specimens are performed, noting the location from which cancer-containing cores were taken aids in treatment planning. However, many institutions include several cores in a single container, to cut costs. We have tried several methods of ink application and combining ink-labeled biopsy specimens into fewer containers with the goal of maintaining information regarding location while minimizing the expense. METHODS. Several approaches to the application of tissue-marking ink to biopsy cores, core-preparation methods, color combinations, and numbers of cores in each container were assessed. RESULTS. The ink adheres well to dry cores, but these cores often exhibit dehydration artifact. Placing the cores on a wet sponge avoids dehydration but causes ink spread. Excessive ink application occurs with eyedroppers and syringes but is avoided by touching each core with an ink-moistened cotton swab. Application of 1% acetic acid to the inked core promotes congealing of the ink onto the tissue. Yellow, orange, and red ink are more difficult to distinguish than blue, black, or green. Deciphering distinct cores when three or more cores are combined is difficult, especially if cores are fragmented. CONCLUSIONS. With our current protocol, all biopsy specimens are placed on separate moistened gauze sponges. Specimens from the right side of the prostate are marked by green ink, and those from the left side are marked by black ink with a cotton swab. After applying 1% acetic acid to each core, the left and right cores from each location are placed in a single container. This method curbs pathology expenses and maintains tumor location information.