Everyone who’s ever seen “CSI: Crime Scene Investigation” knows about crime labs. But few people have ever heard of a pathology lab. As one of the largest departments at Orange Coast Memorial, this highly specialized facility is directed by a pathologist—a physician who identifies diseases by examining fluids and tissue samples under a high-powered microscope. One of the many divisions in this large lab is called histology. It’s the place where specimens removed during surgery are sent for analysis under a microscope to detect the presence and extent of cancer and other diseases.
Recently, Orange Coast Memorial became one of the first hospitals in the nation to adopt a large-format histology slide system to examine these samples. Considered a significant step forward in the field of pathology, the new system is indicative of the hospital’s commitment as a center of excellence in cancer care.
“Before the doctor can evaluate a tissue sample, it must be processed in different chemicals and finally after 48 hours, it’s set in a special material such as paraffin wax,” says Julio Ibarra, M.D., medical director of breast pathology at Orange Coast Memorial. “Then it’s sliced into sections thinner than the average cell, stained, mounted on glass slides, and examined under a microscope.” The result is a panoramic view of the tissue sample, clearly revealing to the trained eye the exact nature, size and characteristics of the tumor, the surrounding tissues, and whether the surgical margin of tissue surrounding the growth is free of abnormal cells.
Until recently, however, pathologists had no choice but to use slides that were the size of a standard Band-Aid. These slides could accommodate a tissue sample no larger than a postage stamp. As a result, pathologists had to piece several slides together to see an entire tumor and its surroundings—a process similar to assembling a difficult jigsaw puzzle.
Now, however, Orange Coast Memorial’s new large-format histology system allows pathologists to use glass slides about the size of a 3- by 5-inch card. As a result, pathologists can examine cross-sections of an entire tumor on one slide instead of using several smaller ones that need to be pieced together. “Imagine looking at a map of California, then viewing the state on separate pages in a guide,” says Dr. Ibarra. “The fragmented view needs to be put together much like a puzzle before you can see how big California is—and assembling the pieces increases the chance for error. On the other hand, the intact map provides a reliable and comprehensive overview of the state and its surroundings.”
Because the entire tumor can be viewed on one slide, the result is greater diagnostic accuracy. Breast cancer patient Diana Thomas appreciates this new development. In January 2007, a routine mammogram at the MemorialCare Breast Center at Orange Coast Memorial revealed several suspicious lumps. To confirm this finding, doctors performed two needle core biopsies, followed by ultrasound, PET, CT and 3-D MRI testing. The diagnosis: Diana had three aggressive cancerous tumors in her right breast. Once her surgery was completed, Dr. Ibarra received Diana’s tissue specimens in the pathology lab and his team began the labor-intensive task of preparing the large-format slides for examination. Their goal was to confirm that all three tumors had been completely removed by comparing the large-format findings with previous imaging studies. “Patients are rarely aware of what happens to their tissue samples when they go to pathology,” says Dr. Ibarra. “But this is an extremely important step in their care. With the large-format histology technique, additional tumors are found in 15 to 20 percent of all cases. In Mrs. Thomas’ case, we had the ability to visualize all three areas of tumor in one large format slide and could correlate this with the radiology findings to confirm that they indeed had been removed.”