Effect of prostate biopsies core number on correlation of needle biopsies and radical prostatectomy’s gleason score

Abstract

Purpose: Today, the gold standard way to diagnosis of prostat cancer is ultrasound (US)- guided biopsy. General literature suggests 12 core samples, although lower core samples are sometimes done for diagnosis. In this study we researched to find effect of sampling number on gleason score of prostate biopsy and radical prostatectomy. 

Materials and Methods: In our clinic, 203 patients who have diagnosed prostate adenocarsinom by transrectal ultrasound guided prostate biopsy because of suspicious fo prostat cancer between march 2011 and february 2016 were included to our study. Patients were divided into two groups according to the number of samples. The first group named extended biopsy group includes 12 and above samples taken patients and the second group named limited biopy group includes less than 12 samples. Both the group’s relations with the biopsy and prostatectomy gleason scores were evaluated individually and were investigated statistically significancy. 

Results: Extended biopsy group consisted of 94 patients, in this group the mean age was calculated 65 years, mean PSA level was 7,6 ng/ mL and mean positive sample/ overall sample was 4,4/12,4. limited biopsy group consisted of 109 patients, in this group the mean age was calculated 61,9 years, mean PSA level was 10,5 ng/mL and mean positive sample/ overall sample was 3,6/10,2. There was no statistically significant difference between both age groups and in PSA levels. When looking at all patients; in 120 patients of all (59.1%) were the same as the final Gleason score and biopsy Gleason score, in 64 cases (31.6%) the final score higher, in 19 cases (9.3%) have less than the final Gleason score. 59 patients(% 62.8) of extended group had the same score, 23 patients(% 24.5) had higher score and 12 patients (% 12.7) had less final gleason score. 61 patients(% 56) of limited group had the same score, 41 patients(% 37,6) had higher score and 7 patients (% 6,4) had less final gleason score. 

Conclusions: Extended prostate needle biopsy improves the probability of detection of prostat canser and has more consistent Gleason scores than limited biopsy. Consistency with the final pathological gleason score on extended biopsy was found more statictical significancy. The increase or decrease in final gleason score was more often seen on biopsy that was taken less sample and so It makes questionable the accuracy of the choice of treatment. 

Keywords

• Prostate Cancer; Needle biopsy; Gleason score
• radical prostatectomy

Prostat iğne biyopsisi örneklem sayısının radikal prostatektomi ve biyopsi gleason skorlarının korelâsyonuna etkisi

Abstract

Amaç: Prostat kanserinde halen altın standart tanı yöntemi ultrasonografi eşliğinde prostat iğne biyopsisidir. Genel literatür 12 kadran biyopsiyi önermekte iken tanı için halen daha az sayılı örneklemeler de yapılmaktadır. Bu çalışmada örnekleme sayısının hem biyopside hem de radikal prostatektomide ki Gleason skoruna etkisini araştırdık. 

Gereç ve Yöntem: Kliniğimizde Mart 2011 ile Şubat 2016 tarihleri arasında prostat kanseri şüphesiyle transrektal ultrasonografi eşliğinde prostat biyopsisi yapılıp patolojisi prostat adenokarsinom gelen 203 hasta çalışmaya alındı. Hastalar örnekleme sayılarına göre 2 gruba ayrıldı. İlk grup 12 kadran ve üzeri örnekleme yapılan genişletilmiş biyopsi grubu iken ikinci grup 12 kadran altı örnekleme yapılan hastalardan oluşan sınırlı biyopsi grubu idi. Her iki grubunda biyopsi ve prostatektomi Gleason skorları ile ilişkileri ayrı ayrı değerlendirilerek istatistiksel olarak anlamlılık araştırıldı. 

Bulgular: Genişletilmiş biyopsi grubu 94 hastadan oluşmakta, ortalama yaşları 65 yıl, ortalama PSA seviyeleri 7.6 ng/mL ve ortalama pozitif / toplam kor sayısı 4.4/12.4 tanedir. Sınırlı biyopsi grubu ise 109 hastadan oluşurken, yaş ortalaması 61.9 yıl, PSA ortalaması 10.5 ng/mL ve ortalama pozitif / toplam kor sayısı 3.6/10.2 tanedir (Tablo 1). Her iki gruptaki yaş ve PSA seviyeleri arasında istatistiksel olarak anlamlı fark bulunmamıştır. Tüm hasta grubuna bakıldığında 120 olguda (%59.1) nihai Gleason skoru biyopsi Gleason skoru ile aynı iken, 64 olguda (% 31.6) nihai skor daha yüksek, 19 olguda (% 9.3) ise nihai Gleason skoru daha düşük gelmiştir. Genişletilmiş prostat biyopsisi yapılan olguların 59 tanesi (% 62.8) aynı, 23 tanesi (% 24.5) yüksek, 12 tanesi (% 12.7) ise düşük skora sahiptir. Sınırlı grupta ise 61 olguda (% 56) aynı skor, 41 olguda (% 37.6) yükselme ve 7 olguda (% 6.4) skorda düşme olmuştur (Tablo 2). 

Sonuç: Genişletilmiş prostat iğne biyopsisi kanser saptanma olasılığını artırmakla birlikte sınırlı gruba göre Gleason skorları arasında daha tutarlı bir sonuç elde etmiştir. Genişletilmiş grupta nihai patoloji Gleason skorunun biyopsi Gleason skoru ile tutarlılığı istatistiksel olarak daha anlamlı gelmiştir. Biyopsi sayısı az olan olgularda Gleason skorlarının artışı veya azalması daha sık görülmüş ve bu bulguda tedavinin seçiminin doğruluğunu tartışılır hale getirmektedir. 

Keywords

• Prostat Kanseri
• İğne biyopsisi
• Gleason Skoru
• Radikal Prostatektomi

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