Extracapsular extension found in nearly 60% of men with tumor cells at the end of a needle core.
DENVER—The presence of tumor cells at the end of a needle biopsy core obtained near the capsule is an independent indicator of a significantly elevated risk of extracapsular extension, according to data presented here at the annual meeting of the United States and Canada Academy of Pathology.
In a study of 185 men who underwent radical prostatectomies who were available for tumor-stage follow-up, Kirk Ke Lin, MD, director of genitourinary pathology at AmeriPath, Inc., discovered that 50.9% of cases with cancerous cells in the end of the needle core near the capsule had stage pT3a or pT3b prostate cancer compared with just 16.2% of cases that did not have cancerous cells and the core’s end.
Furthermore, 13 of 21 men (61.9%) with prostate cancer at the needle core end who had advanced tumor stage also had perineural invasion. Fifty-five men had prostate cancer cells at the end of the needle biopsy core near the capsule at initial biopsy. Their average PSA level was 8.3 ng/mL compared with 6.6 ng/mL for the 130 patients without tumor cells at the core end.
“If these findings are validated in a larger study, it will provide very important information for treatment planning,” Dr. Lin noted. “If the cancer is at the end of a needle core from the right lateral prostate, the surgeon can go around the right lateral prostate to get a clear cut during the prostatectomy. [Or] if there is perineural invasion present in the core-end cancer, a nerve-sparing prostatectomy should not be chosen.”
A prominent urologic oncologist, however, questions the importance of the new findings. “I think it’s intriguing but I’m skeptical, because there are a lot of potential pitfalls in the way he did the study,” said Peter Scardino, MD, of Memorial Sloan-Kettering Cancer Center in New York, where he is the Florence and Theodore Baumritter/Enid Ancell Chair of Urologic Oncology.
“We [already] know that the more cancer there is in a needle biopsy core, the higher the probability a cancer is extracapsular and the higher the Gleason score in the radical prostatectomy specimen. The finding of cancer in one or both ends of a core may simply mean that more cancer was present. We’ll have to await further studies before these findings are accepted.”