This subject has been raised many times over the years since I took a personal interest in such issues, but it is some time since I looked into it at any depth, mainly because I came to a conclusion and decided that unless I came across further evidence, I would not waste more time on the subject.
The first study I saw on this subject was done in 1991 and concluded that cancer cells might well be deposited in the needle tracks – and circulate in the bloodstream afterwards (1). The general view in discussions was that these cells would not ‘take root’ so to speak and develop into metastasised disease. As far as I know the study has never been repeated and there have never been any follow up studies that indicates this is a problem. Dr Walsh, who was a participant in this study, refutes the implications of the study in his most recent book and writings. In "Dr. Patrick Walsh's Guide to Surviving Prostate Cancer" he responds to the question "If I have cancer, will the biopsy spread it?" by saying "...the good news is that there is no evidence that this is has ever happened." He emphasizes his response by putting it in italics. He clearly doesn't want to convey the idea that there's a problem, but you have to be careful in understanding that like the well known quote “I did not have sex with this woman” words can be very carefully chosen – and the lack of ‘evidence’ may simply mean that no one has looked for it.
So, while it's true that this is the only study to show spread of cancer along biopsy tracks after transrectal biopsy, scattered reports of tumor seeding along transperineal biopsy tracks have appeared for more than 25 years (2-9 ), including a report of tumor recurrence along such a track 14 years after a prostatectomy (10 ).
(1) J Urol 1991 May;145(5):1003-7 Needle biopsy associated tumor tracking of adenocarcinoma of the prostate. Bastacky SS, Walsh PC, Epstein JI. Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland. We reviewed 350 previously biopsied completely submitted clinical stage B radical prostatectomy specimens resected between January 1, 1987 and December 31, 1988 in an attempt to identify the incidence of needle biopsy associated tumor tracking into periprostatic soft tissue. We identified 7 cases (2.0%) of needle biopsy associated tumor tracking, 3 in which the only tumor penetration in the gland was limited to the needle track. The maximal soft tissue extension from the biopsy site ranged from 0.1 to 1.2 cm. and approached the nearest soft tissue margin to within 0.5 mm. in 4 cases. In contrast to prior reports showing clinically evident tracking only with transperineal biopsies from high grade tumors, 6 of our 7 cases were of intermediate grade (in the glandular and tracking components) and 6 had transrectal biopsies. Needle biopsy associated tumor tracking occurred with core (14 gauge) and biopsy gun needles (18 gauge). An additional 13 cases (3.7%) showed some features of needle biopsy associated tumor tracking but they were equivocal. These findings have significant implications in light of recent proposals advocating serial mapping of prostate cancer using the biopsy gun with potential conservative observation of smaller tumors.
(2)Urology 1976 Nov;8(5):513-5 Perineal seeding of prostatic carcinoma after needle biopsy. Addonizio JC, Kapoor SN. "We recommend that a sterilizing dose of radiotherapy be given to the perineum after perineal needle biopsy."
(3) Urology 1986 Jun;27(6):548-9 Extension of carcinoma of prostate along perineal needle biopsy tract. Emtage JB, Perez-Marrero R.
(4)J Surg Oncol 1987 Jul;35(3):184-91 Seeding and perineal implantation of prostatic cancer in the track of the biopsy needle: three case reports and a review of the literature. Haddad FS, Somsin AA. (subcutanous tumor nodule after 0.34% of biopsies)
(5)Urology 1989 Jan;33(1):59-60 Late appearance of perineal implantation of prostatic carcinoma after perineal needle biopsy. Greenstein A, et al. Tel Aviv University, Israel.
(6)J Urol 1989 Jul;142(1):86-8 Risk factors for perineal seeding of prostate cancer after needle biopsy. Moul JW, et al. Walter Reed Army Medical Center, Washington, D.C. (perineal seeding in 1% of positive biopsies)
(7)Eur Urol 1990;17(2):189-92 Perineal prostatic tumour seedling after 'Tru-Cut' needle biopsy: case report and review of the literature. Ryan PG, Peeling WB. Newport, UK.
(8)Urol Int 1990;45(6):370-1 Perineal seeding of prostatic carcinoma after Trucut biopsy. Baech J, et al. Copenhagen, Denmark.
(9)Int Urol Nephrol 1996;28(1):87-90 Perineal prostatic cancer seeding following Urocut needle biopsy. Szentgyorgyi E. Vac, Hungary.
(10)Urology 1998 Jan;51(1):158-60 Perineal seeding of prostate cancer as the only evidence of clinical recurrence 14 years after needle biopsy and radical prostatectomy: molecular correlation. Moul JW, et al. Walter Reed Army Medical Center, Washington, DC, USA
