Health-related quality of life in Japanese low-risk prostate cancer patients choosing active surveillance: 3-year follow-up from PRIAS-JAPAN

Active Surveillance for Taiwanese Men with Localized Prostate Cancer: Intermediate-Term Outcomes and Predictive Factors

PURPOSE

Active surveillance (AS) is one of the management options for patients with low-risk and select intermediate-risk prostate cancer (PC). However, factors predicting disease reclassification and conversion to active treatment from a large population of pure Asian cohorts regarding AS are less evaluated. This study investigated the intermediate-term outcomes of patients with localized PC undergoing AS.

MATERIALS AND METHODS

This cohort study enrolled consecutive men with localized non-high-risk PC diagnosed in Taiwan between June 2012 and Jan 2023. The study endpoints were disease reclassification (either pathological or radiographic progression) and conversion to active treatment. The factors predicting endpoints were evaluated using the Cox proportional hazards model.

RESULTS

A total of 405 patients (median age: 67.2 years) were consecutively enrolled and followed up with a median of 64.6 months. Based on the National Comprehensive Cancer Network (NCCN) risk grouping, 70 (17.3%), 164 (40.5%), 140 (34.6%), and 31 (7.7%) patients were classified as very low-risk, low-risk, favorable-intermediate risk, and unfavorable intermediate-risk PC, respectively. The 5-year reclassification rates were 24.8%, 27.0%, 18.6%, and 25.3%, respectively. The 5-year conversion rates were 20.4%, 28.8%, 43.6%, and 37.8%, respectively. A prostate-specific antigen density (PSAD) of ≥0.15 ng/mL² predicted reclassification (hazard ratio [HR] 1.84, 95% confidence interval [CI] 1.17-2.88) and conversion (HR 1.56, 95% CI 1.05-2.31). A maximal percentage of cancer in positive cores (MPCPC) of ≥15% predicted conversion (15% to <50%: HR 1.41, 95% CI 0.91-2.18; ≥50%: HR 1.97, 95% CI 1.1453-3.40) compared with that of <15%. A Gleason grade group (GGG) of 3 tumor also predicted conversion (HR 2.69, 95% CI 1.06-6.79; GGG 3 vs 1). One patient developed metastasis, but none died of PC during the study period (2,141 person-years).

CONCLUSIONS

AS is a viable option for Taiwanese men with non-high-risk PC, in terms of reclassification and conversion. High PSAD predicted reclassification, whereas high PSAD, MPCPC, and GGG predicted conversion.

Outcomes of active surveillance for Japanese patients with prostate cancer (PRIAS-JAPAN)

OBJECTIVE

To report the outcomes of repeat biopsies, metastasis and survival in the Prostate Cancer Research International: Active Surveillance (PRIAS)-JAPAN study, a prospective observational study for Japanese patients, initiated in 2010.

PATIENTS AND METHODS

At the beginning, inclusion criteria were initially low-risk patients, prostate-specific antigen (PSA) density (PSAD) <0.2, and ≤2 positive biopsy cores. As from 2014, GS3+4 has also been allowed for patients aged 70 years and over. Since January 2021, the age limit for Gleason score (GS) 3 + 4 cases was removed, and eligibility criteria were expanded to PSA ≤20 ng/mL, PSAD <0.25 nd/mL/cc, unlimited number of positive GS 3 + 3 cores, and positive results for fewer than half of the total number of cores for GS 3 + 4 cases if magnetic resonance imaging fusion biopsy was performed at study enrolment or subsequent follow-up. For patients eligible for active surveillance, PSA tests were performed every 3 months, rectal examination every 6 months, and biopsies at 1, 4, 7 and 10 years, followed by every 5 years thereafter. Patients with confirmed pathological reclassification were recommended for secondary treatments.

RESULTS

As of February 2024, 1302 patients were enrolled in AS; 1274 (98%) met the eligibility criteria. The median (interquartile range) age, PSA level, PSAD, and number of positive cores were 69 (64-73) years, 5.3 (4.5-6.6) ng/mL, 0.15 (0.12-0.17) ng/mL, and 1 (1-2), respectively. The clinical stage was T1c in 1089 patients (86%) and T2 in 185 (15%). The rates of acceptance by patients for the first, second, third and fourth re-biopsies were 83%, 64%, 41% and 22%, respectively. The pathological reclassification rates for the first, second, third and fourth re-biopsies were 29%, 30%, 35% and 25%, respectively. The 1-, 5- and 10-year persistence rates were 77%, 45% and 23%, respectively. Six patients developed metastasis, and one patient died from prostate cancer.

CONCLUSION

Pathological reclassification was observed in approximately 30% of the patients during biopsy; however, biopsy acceptance rates decreased over time. Although metastasis occurred in six patients, only one death from prostate cancer was recorded.

Active surveillance in younger patients with prostate cancer: clinical characteristics including longitudinal patient-reported outcomes

OBJECTIVE

this study aimed to evaluate the active surveillance continuation period, treatment intervention rate and health-related quality of life in younger patients.

METHODS

we prospectively conducted a health-related quality of life survey of patients enrolled in the Prostate Cancer Research International: Active Surveillance-JAPAN study at Kagawa University between January 2010 and December 2020. Health-related quality of life was assessed by mail using a validated Japanese version of the Short-Form 8 Health Survey and Expanded Prostate Cancer Index at active surveillance enrolment and annually thereafter until discontinuation of active surveillance. We divided the patients into two groups, younger (aged <65 years) and older (aged ≥65 years), and compared the two groups.

RESULTS

of the 84 patients, 22 were in the younger group. The active surveillance continuation period was shorter in the younger group than in the older group. The 3-year treatment intervention rate was higher in the younger group than in the older group. The majority of the reasons for definitive treatment were related to the protocol, which was similar in both groups (80 versus 76%). The sexual summary scores at active surveillance enrolment were higher in the younger group than in the older group. During active surveillance, the younger group and the older group showed no deterioration in all health-related quality of life scores compared with the scores at the enrolment of active surveillance.

CONCLUSIONS

patient-reported health-related quality of life survey indicated that the health-related quality of life of younger Japanese patients was maintained over time during active surveillance, similar to that of older patients.

Reclassification prediction of first-year protocol biopsy on active surveillance of prostate cancer by p2PSA-related parameters: from PRIAS-JAPAN

BACKGROUND

There is no useful predictive marker for reclassification on active surveillance. Thus, we aimed to investigate thresholds of [-2] proPSA (p2PSA)-related parameters to predict reclassification of the first-year protocol biopsy (1-year PBx) and evaluate the influence of clinical decision-making.

METHODS

This was an observational, prospective cohort study conducted at 19 Japanese institutes. The inclusion criteria included clinical stage T1c/T2, prostate-specific antigen (PSA) levels ≤10 ng/mL, PSA density <0.2 ng/ml/cc, one or two positive biopsy cores, and Gleason score (GS) ≤6 (GS ≦7 for patients aged ≥70 years) at diagnostic biopsy. All participants were required to receive a blood-sampling test on a protocol visit at inclusion and at the 1-year PBx. PSA and PSA isoforms (free PSA, p2PSA) were measured, and parameters (%free PSA, %p2PSA, phi) were calculated. Multivariable logistic regression models were used to predict the reclassification risk. To assess the predictive power and thresholds for reclassification, we plotted Receiver Operating Characteristic (ROC) curves. Decision curve analysis (DCA) was used to evaluate the variables that yielded a net clinical benefit.

RESULTS

A total of 135 patients were included, and 36 patients were reclassified on the 1-year PBx. Multivariate analyses showed that %p2PSA and phi at inclusion and p2PSA, %p2PSA, and phi before the 1-year PBx were significant predictors of reclassification at the 1-year PBx. The ROC analysis showed an optimal cutoff point, sensitivity, and specificity of %p2PSA and phi before the 1-year PBx of 1.64, 86%, 49% and 35.92, 89%, 47%, respectively. The DCA showed that phi before the 1-year PBx had the highest net benefit. The study limitation was its single-arm observational design.

CONCLUSIONS

%p2PSA and phi before the 1-year PBx had a good prediction power. phi is the most useful indicator for clinical decision-making on active surveillance.

TRIAL REGISTRATION

This study is registered atthe Japan Trial Register with ID UMIN000009876 ( https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000011573 ).

Comparison of Characteristics, Follow-up and Outcomes of Active Surveillance for Prostate Cancer According to Ethnicity in the GAP3 Global Consortium Database

BACKGROUND

Studies of active surveillance (AS) for prostate cancer (PCa) have focussed predominantly on Caucasian populations. Little is known about the experience of Asian men, while suitability for men of African descent has been questioned.

OBJECTIVE

To compare baseline characteristics, follow-up, and outcomes for men on AS for PCa, according to ethnicity.

DESIGN SETTING AND PARTICIPANTS

The study cohort included 13 centres from the GAP3 consortium that record ethnicity (categorised broadly as Caucasian/white, African/Afro-Caribbean/black, Asian, mixed/other, and unknown). Men with biopsy grade group >2, prostate-specific antigen (PSA) >20 ng/ml, T stage ≥cT3, or age >80 yr were excluded.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Clinical characteristics, follow-up schedules, outcome status, and reasons for discontinuation were compared across ethnic groups. Risk of upgrading, potential disease progression (grade group ≥3 or T stage ≥3), suspicious indications (any upgrading, number of positive cores >3, T stage ≥cT3, PSA >20 ng/ml, or PSA density >0.2 ng/ml/cc²), and conversion to treatment were assessed using mixed-effect regression models.

RESULTS AND LIMITATIONS

The eligible cohort (n = 9158) comprised 83% Caucasian men, 6% men of African descent, 5% Asian men, 2% men of mixed/other ethnicity, and 4% men of unknown ethnicity. Risks of suspicious indicators (hazard ratio = 1.27; 95% confidence interval [CI] 1.12-1.45), upgrading (odds ratio [OR] = 1.40; 95% CI 1.14-1.71), and potential progression (OR = 1.46; 95% CI 1.06-2.01) were higher among African/black than among Caucasian/white men. Risk of transitioning to treatment did not differ by ethnicity. More Asian than Caucasian men converted without progression (42% vs 26%, p < 0.001). Heterogeneity in surveillance protocols and racial makeup limit interpretation.

CONCLUSIONS

This multinational study found differences in the risk of disease progression and transitioning to treatment without signs of progression between ethnic groups. Further research is required to determine whether differences are due to biology, sociocultural factors, and/or clinical practice.

PATIENT SUMMARY

This international study compared prostate cancer active surveillance outcomes by ethnicity. Risks of upgrading and disease progression were higher among African than among Caucasian men. Transitioning to treatment without progression was highest among Asian men. Understanding of these differences requires further investigation.

A randomized controlled trial evaluating the effect of low-dose chlormadinone in patients with low-risk prostate cancer: PROSAS study

OBJECTIVES

This study was conducted to evaluate the effect of low-dose chlormadinone acetate, an antiandrogen agent, on the persistence rate of active surveillance in patients with low-risk prostate cancer.

METHODS

The study was a multicenter, placebo-controlled, double-blind, randomized controlled trial conducted at 38 sites in Japan. Low-risk prostate cancer patients were randomly assigned to the chlormadinone group or the placebo group and the persistence rate of active surveillance was evaluated for 3 years.

RESULTS

Seventy-one patients in the chlormadinone group and 72 patients in the placebo group were analyzed. The persistence rate of active surveillance [95% CI] at 3 years was 75.5% [62.5-84.6] in the chlormadinone group and 50.1% [36.7-62.2] in the placebo group, showing a significant difference between the groups (P = 0.0039). The hazard ratio [95% CI] of the chlormadinone group to the placebo group for discontinuation of active surveillance was 0.417 [0.226-0.770]. The chlormadinone group showed a significant decrease in prostate specific antigen level, testosterone level and prostate volume. The number of positive cores at 12 and 36 months biopsy was significantly lower in the chlormadinone group. The incidence of adverse events was 43.7% in the chlormadinone group and 12.5% in the placebo group. The most common adverse event in the chlormadinone group was constipation in 22.5%, followed by hepatobiliary disorders in 9.9%.

CONCLUSIONS

In patients with low-risk prostate cancer, low-dose chlormadinone showed a reduced number of positive cores and prostate volume, and an increased persistence rate of active surveillance (UMIN000012284).

Long-term outcomes of androgen deprivation therapy in prostate cancer among Japanese men over 80 years old

This study aimed to analyze the survival rate and to examine the risk of death from prostate cancer when accounting for competing risk of death, in men aged ≥80 y treated with primary androgen deprivation therapy (ADT). Data of patients with prostate cancer who had received ADT were extracted from a nationwide community‐based database established by the Japan Study Group for Prostate Cancer. Prognostic variables, including progression‐free survival, cancer‐specific survival, overall survival, and death rates were compared between men stratified by prostate cancer risk. Overall, 4760 patients older than 80 y were included. The proportion of low‐, intermediate‐, high‐, or very high‐risk, regional, and metastatic prostate cancer among super‐elderly men was 9.5%, 14.6%, 48.8%, 9.0%, 3.2%, and 24.9%, respectively. Survival rates decreased with increasing risk stratification. The cumulative 5‐y death rate by prostate cancer for low‐, intermediate‐, high‐, or very high‐risk, regional, and metastatic prostate cancer, was 0.92% (95% confidence interval [CI]: 0.2%‐3.6%), 1.6% (95% CI: 0.8%‐3.4%), 5.75% (95% CI: 4.25%‐7.75%), 15.6% (95% CI: 11.6%‐23.3%), 20.7% (95% CI: 13.1%‐31.7%), and 36.9% (95% CI: 32.8%‐41.4%), respectively. Our findings support that there is no need for immediate ADT for low‐ and intermediate‐risk groups. Conversely, in high‐ or very high‐risk, regional, and metastatic prostate cancer, more efforts for curative therapy and intensive therapy are needed in selected patients.

Impact of health-related quality of life on repeat protocol biopsy compliance on active surveillance for favorable prostate cancer: results from a prospective cohort in the PRIAS-JAPAN study

OBJECTIVES

This study aimed to evaluate how health-related quality of life (HRQOL) is related to repeat protocol biopsy compliance.

MATERIALS AND METHODS

We conducted a retrospective analysis using data from a prospective cohort in the Prostate Cancer Research International: Active Surveillance (PRIAS)-JAPAN study between January 2010 and August 2019. We used the Short Form 8 Health Survey (SF-8), as patient-reported outcomes, to assess HRQOL at AS enrollment and the first year of the protocol. The physical component summary (PCS) and mental component summary (MCS) were calculated from SF-8 questionnaires. The primary outcome was the evaluation of the association of HRQOL at enrollment on the first repeat biopsy compliance. The secondary outcome was the comparison of SF-8 scores during AS, stratified by repeat protocol biopsy compliance.

RESULTS

Of 805 patients who proceeded to the first year of the protocol, the non-compliance rate was 15% (121 patients). In the adjusted model, lower MCS at enrollment was significantly associated with the first repeat protocol biopsy non-compliance (odds ratio [OR], 2.134; 95% confidence interval [CI], 1.031-4.42; P = 0.041) but not in lower PCS (OR, 0.667; 95% CI, 0.294-1.514; P = 0.333). All subscales of SF-8 were lower in the non-compliance group than in the compliance group at any point. MCS in the non-compliance group improved over time from the time of AS enrollment (2.34 increased, P = 0.152).

CONCLUSION

Our data suggest that lower MCS at AS enrollment using patient-reported outcomes was negatively associated with the first repeat protocol biopsy compliance. Our study may support the availability of a simple questionnaire to extract non-compliance.