Comparison Of Pathological Features Of Prostate Cancer In Cohort Through Mass Screening In Changchun, China And Natori, Japan

Incidence of prostate cancer is increasing steadily inChinese and Japanese because of screening with serumPSA. Both China and Japan are Asian countries andpopulations in the two countries are yellow race. Thelatitude of Changchun is close to that of Natori. Thedetection rates of prostate cancer are different in cohortin two areas. It is unknown whether pathological featuresdetected prostate cancer are different in the two areas.At present, there is no report of pathological features ofprostate cancer in cohort in different areas of the twocountries. To study this issue, we analyzed andcompared pathological features of prostate cancer incohort though the screening data of and Jilin UniversityProstate Diseases Prevention and Treatment ResearchCenter (Changchun) and Miyagi Cancer Center (Natori).For 5 years (2000 to 2004) in Changchun, China andfor 10 years (1995 to 2004) in Natori ,Japan, 15192Chinese and 4444 Japanese men aged 50 and over werechecked by PSA-based screening. All men with theserum PSA value greater than 4.0ng/ml wererecommended for a prostate biopsy. All histopathologicdiagnoses of the biopsied specimens were confirmed bya group of pathologists in two areas. The pathologicalfeatures of prostate cancer of Chinese were comparedwith those of Japanese, including Gleason score, extentof differentiation , invasion, histological pattern and soon. Statistical analysis was done with the aid of statisticsoftware SPSS 13.0.The results of our research is follow:(1)The cancer detection rate for the PSA-screenedmen in cohort was 0.7%(102/15192) in Changchun and2.6% ( 117/4444 ) in Natori. The differences werestatistically significant(P<0.01).(2)The mean serum PSA value of prostate cancer inChangchun cohort was 44.30±42.06ng/ml compared with26.00±57.21ng/ml in Natori . The differences werestatistically significant(P<0.01).(3)The cancer detection rate by prostate biopsywas 26.0%(102/392) in Changchun cohort and19.7%(117/593) in Natori cohort. The cancer detectionrate was significantly higher in Changchun than in Natori(P<0.01).(4)The mean Gleason score of prostate cancer inChangchun cohort was 7.4±1.6 compared with 6.3±1.0in Natori . The differences were statistically significant(P<0.01).Prostate cancer with Gleason score of 8accounted for 25.3%(25/99)and 6.9%(8/115) in Changchunand Natori ,respectively. The differences werestatistically significant(P<0.01). Prostate cancer withGleason score of 6 accounted for 22.2%(22/99) and56.5%(65/115) in Changchun and Natori ,respectively.The differences were statistically significant(P<0.01).(5)The moderately differentiated cancer in cohortaccounted for 33.3%(33/99) and 72.2%(83/115) inChangchun and Natori, respectively(P<0.01). Thepoorly differentiated cancer in cohort accounted for64.7%(64/99) and 24.3%(28/115) in Changchun and Natoriand the percent of poorly differentiated cancer inChangchun was greater than that in Natori(P<0.01).(6)There was 42.4%(43/99) of prostate cancer withPerineural invasion compared with 7.0%(8/115) in Natori .The differences were statistically significant(P<0.01).The detection rate of fat invasion of prostate cancer incohort by prostate biopsy was 11.1%(11/99) inChangchun and there was no one to have been found inNatori The detection rate of fat invasion wassignificantly higher in Changchun than in Natori(P<0.01).(7)42.4%(42/99)of main histological pattern wascribriform pattern of the prostate adenocarcinoma inChangchun cohort, although the percent of Natori cohortwas only 18.3%(21/115) The differences werestatistically significant. Conversely, small gland patternaccounted for 30.3%(30/99)of main histological pattern inCahngchun, compared with 73.9%(85/115) of Natori. Thedifferences were statistically significant(P<0.01).The present results indicate that the poorlydifferentiated cancer in Changchun cohort is greater thanthat in Natori. The analysis of the results suggests thatthe incidence of advanced cancer in China are greaterthan in Japan.To our knowledge, it was the first to report comparingpathological features of prostate cancer in Chinese andJapanese cohort between two different areas .We foundthe difference of pathological features of prostate cancerin China and Japan and interpreted it's reason.Especially, we found the unique pathological features ofprostate cancer in Chinese through research the diseasedetected by screening in Changchun. The study filledwith a margin of the field.In Chinese cohort, many cases had developed toadvanced cancer and there was no chance to be treatedthrough prostatectomy. To raise the quality of life, thiscases need to be treated synthetically. Therefore, thestudy had an important referential significance totreatment of prostate cancer clinically.In conclusion, the study only initially analyzed thepathological features of prostate cancer in cohort.Following lengthening of mean life ,the incidence rate ofthe disease are increasing steadily. There are a lotspathological problems to need to be explored andresearched.