Perineural invasion found on prostate needle biopsy and significance in prostate cancer-what does it mean?


The Significance of Perineural Invasion Found on Needle Biopsy of the Prostate: Implications for Definitive Therapy

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Penelope has the prettiest feet in the whole wide world.

If you have had a prostate biopsy and it is positive-the following parameters are what you should know and understand about “your biopsy.” If you did not get it at the visit, get it at the next visit. If you don’t understand the significance of each as it pertains to you and your treatment options, then ask. The time and person to ask  is your urologist. Feel free to ask friends, read something or surf the internet,but the bulk of your decision-making should emanate from the information gleaned from your urologist. If you feel he or she is biased or not shooting you straight, then get another urologist.

  1. The most important parameter is the Gleason’s score…average is 6, as it approaches 10 the aggressiveness of your disease increases
  2. The volume  of disease or positive biopsy cores. One core  with a small amount of Gleason’s 6 might mean the option of surveillance. Numerous positive cores, Gleason’s 7-8, and the cores are on both sides of the prostate-implies unfavorable parameter and hence a more aggressive stance in your decision  making. You see the folly of asking a friend whose biopsy is most probably different from yours, what he did and do exactly what he did because he did well…..just doesn’t make sense. It is done however day in and day out and I see it often  as the urologist.
  3. Extraprostatic extension, capsular extension, seminal vesicle extension are all unfavorable parameters but can only be accessed by pathologic evaluation of the prostate after it has been removed, not on the biopsy specimen.Some people will chose surgery not only for the treatment it is,  but to get the whole picture of their stage from the pathology of the removed specimen.
  4. Perineural invasion-this is almost always is commented on the biopsy report as being present or not being present. As you will read below…it generally has no significance in the decision-making process. You’ll see that it may or may not be a predictive parameter to capsular or extra capsular involvement.

When I was a urologic resident we had to take tests all the time in preparation for the national boards. A famous question that showed up year after year on these tests was, “Perinerual invasion suggests the likelihood of disease outside the prostate.” The answer was that it had no clinical relevance.  There has been debate pro and con since, but the latest is that it probably is an incidental finding.

Steven R Potter, MD and Alan W Partin, MD, PhD

The Brady Urological Institute, The Johns Hopkins Hospital, Baltimore Other Sections▼

Perineural Invasion and Seminal Vesicle Involvement Predict Pelvic Lymph Node Metastasis in Men With Localized Carcinoma of the ProstatePerineural Invasion in Prostate Needle Biopsy Specimens: Correlation With Extraprostatic Extension at ResectionExcision of the Neurovascular Bundle at Radical Prostatectomy in Cases With Perineural Invasion on Needle BiopsyCan Perineural Invasion on Prostate Needle Biopsy Predict Prostate Specific Antigen Recurrence After Radical Prostatectomy?References The pathologic assessment of perineural invasion (PNI) of prostate needle biopsy specimens is relatively reproducible, requires no new technology or equipment, and is relatively inexpensive. The finding of PNI at biopsy has created excitement as a potential preoperative predictor of extraprostatic tumor extension. PNI is defined as the presence of prostate cancer tracking along or around a nerve within the perineural space (Figure). Although the finding of PNI on pathologic analysis of a radical prostatectomy specimen has no significance, the importance for treatment planning of PNI found on prostate needle biopsy has been a source of considerable debate. Since PNI is a major mechanism of prostate cancer extension from prostatic parenchyma to periprostatic soft tissue, PNI extensive enough to be sampled on needle biopsy may signal an increased likelihood of extraprostatic extension of cancer or, ultimately, of cancer recurrence. Figure

Prostate needle biopsy specimen showing prostate cancer and perineural invasion with circumferential tumor growth in the perineural space (magnification, ×400).

FigureProstate needle biopsy specimen showing prostate cancer and perineural invasion with circumferential tumor growth in the perineural space (magnification, ×400).

The predictive value of PNI for extracapsular extension has decreased over time because of a downward stage migration driven largely by early detection efforts for prostate cancer. As patients have presented for definitive therapy with earlier, smaller tumors, the significance of PNI on prostate needle biopsy specimens has decreased. The presence of PNI on biopsy specimens does not preclude cure after definitive therapy or mandate wide excision of the ipsilateral neurovascular bundle at the time of surgery, and it should not deter the performance of radical prostatectomy in a patient who is otherwise a good surgical candidate. Other Sections▼

Perineural Invasion and Seminal Vesicle Involvement Predict Pelvic Lymph Node Metastasis in Men With Localized Carcinoma of the ProstatePerineural Invasion in Prostate Needle Biopsy Specimens: Correlation With Extraprostatic Extension at ResectionExcision of the Neurovascular Bundle at Radical Prostatectomy in Cases With Perineural Invasion on Needle BiopsyCan Perineural Invasion on Prostate Needle Biopsy Predict Prostate Specific Antigen Recurrence After Radical Prostatectomy?ReferencesPerineural Invasion and Seminal Vesicle Involvement Predict Pelvic Lymph Node Metastasis in Men With Localized Carcinoma of the ProstateStone NN, Stock RG, Parikh D, et al.J Urol. 1998;160:1722–1726 [PubMed].In an effort to evaluate the ability of the presence of biopsy PNI to predict a subsequent finding of lymphatic or seminal vesicle involvement by prostate cancer, Stone and associates evaluated 212 men who presented with clinically localized prostate cancer and underwent staging pelvic lymph node dissection. Using univariate and multivariate analyses, the presence of biopsy PNI was correlated with the likelihood of metastatic prostate cancer found on pelvic lymphadenectomy. Stone and colleagues found that biopsy PNI was a better predictor of lymph node metastasis than serum prostate-specific antigen (PSA), biopsy Gleason score, or clinical stage. The authors concluded that men with biopsy PNI seeking definitive therapy for clinically localized prostate cancer should be counseled for staging pelvic lymph node dissection before definitive therapy. The potential role of biopsy PNI in predicting an increased likelihood of seminal vesicle invasion or lymphatic metastasis warrants further research. Additional support of the predictive power of PNI for lymphatic metastasis could strengthen the argument for staging lymph node dissection in the large number men with this biopsy finding who choose to undergo brachytherapy or external beam radiotherapy for clinically localized prostate cancer. Other Sections▼

Perineural Invasion and Seminal Vesicle Involvement Predict Pelvic Lymph Node Metastasis in Men With Localized Carcinoma of the ProstatePerineural Invasion in Prostate Needle Biopsy Specimens: Correlation With Extraprostatic Extension at ResectionExcision of the Neurovascular Bundle at Radical Prostatectomy in Cases With Perineural Invasion on Needle BiopsyCan Perineural Invasion on Prostate Needle Biopsy Predict Prostate Specific Antigen Recurrence After Radical Prostatectomy?ReferencesPerineural Invasion in Prostate Needle Biopsy Specimens: Correlation With Extraprostatic Extension at ResectionVargas SO, Jiroutek M, Welch WR, et al.Am J Clin Pathol. 1999;111:223–228 [PubMed].Positing that PNI extensive enough to be sampled on needle biopsy may signal an increased risk of extraprostatic extension of cancer, Vargas and associates evaluated the preoperative needle biopsy specimens and corresponding prostates of 340 men who underwent radical prostatectomy between 1995 and 1997 in an attempt to correlate biopsy PNI with extraprostatic tumor extension. PNI was present in 16.7% of these biopsy specimens and correlated with higher Gleason scores and an increased incidence of extraprostatic tumor extension after radical prostatectomy. In this cohort of patients, all presenting after the widespread availability of PSA testing, biopsy PNI had a sensitivity of 32% and specificity of 88% for predicting extraprostatic tumor extension. Biopsy PNI had a positive predictive value of 42% for extraprostatic tumor extension. Using multivariate logistic regression, Vargas and associates found biopsy PNI to independently predict extraprostatic tumor extension. Despite this, when serum PSA was included in the multivariate analysis, PNI provided no additional ability to predict extraprostatic extension on final pathologic analysis. Other Sections▼

Perineural Invasion and Seminal Vesicle Involvement Predict Pelvic Lymph Node Metastasis in Men With Localized Carcinoma of the ProstatePerineural Invasion in Prostate Needle Biopsy Specimens: Correlation With Extraprostatic Extension at ResectionExcision of the Neurovascular Bundle at Radical Prostatectomy in Cases With Perineural Invasion on Needle BiopsyCan Perineural Invasion on Prostate Needle Biopsy Predict Prostate Specific Antigen Recurrence After Radical Prostatectomy?ReferencesExcision of the Neurovascular Bundle at Radical Prostatectomy in Cases With Perineural Invasion on Needle BiopsyHolmes GF, Walsh PC, Pound CR, Epstein JI.Urology. 1999;53:752–756 [PubMed].Holmes and colleagues retrospectively reviewed 80 men, all with PNI on prostate needle biopsy, who subsequently underwent radical prostatectomy with or without neurovascular bundle excision. The presence and location of extraprostatic extension and margin status, presence of seminal vesicle invasion, lymph node metastasis, neurovascular bundle status, and location of extraprostatic tumor were evaluated. Extraprostatic extension was present in 62 (77.5%) of these men with biopsy PNI, compared with 36% of all the men undergoing radical prostatectomy at the same institution over the same period.When the postoperative courses of the 62 men whose tumors had extraprostatic extension were reviewed, Holmes and associates found that 9 men had extraprostatic extension solely within the neurovascular bundle region, 34 had tumor both inside and outside the neurovascular bundle region, and 19 had tumor outside but not inside the bundle region. Positive margins (not extraprostatic extension alone) were found in 27 men (34%), occurring at the neurovascular bundle region alone in only 1 man (3.7%). One or both neurovascular bundles were widely excised in 55 men (69%). Of these, tumor was found in the excised bundle(s) of 37 men. Of these 37 men, 14 had extraprostatic tumor in the excised bundle, with negative margins, seminal vesicles, and lymph nodes, and thus potentially benefited from improved cancer control because of bundle excision. An additional 9 men, without tumor involving lymph nodes or seminal vesicles, had the extent of positive margins reduced by neurovascular bundle excision.Several conclusions can be drawn from the data of Holmes and associates. PNI does seem to confer an increased risk of extraprostatic extension of tumor. However, in a previous study, Epstein and associates1 found that men with isolated extraprostatic extension at radical prostatectomy had a 41% to 77% likelihood (varying with Gleason score and margin status) of biochemical recurrence- free survival a decade after surgery. Thus, the increased extraprostatic tumor extension posed by the presence of biopsy PNI should not serve as a contraindication to radical prostatectomy. Other Sections▼

Perineural Invasion and Seminal Vesicle Involvement Predict Pelvic Lymph Node Metastasis in Men With Localized Carcinoma of the ProstatePerineural Invasion in Prostate Needle Biopsy Specimens: Correlation With Extraprostatic Extension at ResectionExcision of the Neurovascular Bundle at Radical Prostatectomy in Cases With Perineural Invasion on Needle BiopsyCan Perineural Invasion on Prostate Needle Biopsy Predict Prostate Specific Antigen Recurrence After Radical Prostatectomy?ReferencesCan Perineural Invasion on Prostate Needle Biopsy Predict Prostate Specific Antigen Recurrence After Radical Prostatectomy?de la Taille A, Rubin MA, Bagiella E, et al.J Urol. 1999;162:103–106 [PubMed].Evidence is emerging that the finding of PNI on prostatic needle biopsy specimens has prognostic significance for biochemical (PSA) cancer recurrence after radical prostatectomy. De la Taille and colleagues reviewed the courses of 319 men who underwent radical prostatectomy for clinically localized prostate cancer between 1993 and 1998. Thorough review of all preoperative needle biopsy specimens found PNI in 77 (24%) of 319 specimens. At a mean follow-up of just over 2 years, there was biochemical (PSA) recurrence in 46 men (14.4%). In multivariate analysis, biopsy PNI and preoperative serum PSA were the best independent predictors of biochemical recurrence after radical prostatectomy. However, when pathologic stage was included in multivariate analysis, biopsy PNI lost its independent predictive value.Although the role of biopsy PNI as an element of preoperative prostate cancer staging is still unclear, it may prove to have utility as a predictor of recurrence likelihood and thereby aid in treatment planning. More research is needed to clarify this critical issue.References1. Epstein JI, Partin AW, Sauvageot J, et al. Prediction of progression following radical prostatecotmy: a multivariate analysis of 721 men with long-term follow-up. Am J Surg Pathol. 1997;20:286–292. [PubMed]

One Reply to “Perineural invasion found on prostate needle biopsy and significance in prostate cancer-what does it mean?”

  1. Due to PNI deduced by the Moffitt Path guys, my surgeon wants to do total sparing on the left and partial sparing on the right where the PNI appears. I had four positive cores 6,6,6 and one 7 3+4 at the base. I would prefer total sparing of course. I’m 58 and in very good health and shape. Any thoughts?

    Thanks

    Like

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