Observations of prostate specific antigen doubling time in Japanese patients with nonmetastatic prostate carcinoma

Clinical significance of the prostate-specific antigen doubling time prior to and following radical prostatectomy to predict the outcome of prostate cancer

With the advent of serum prostate-specific antigen (PSA), a larger number of prostate cancers in the early phase have been successfully detected. Although decisions to perform prostate biopsies are routinely based on PSA levels, the PSA level is easily influenced by benign prostatic hyperplasia, with poor specificity. Therefore, the aim of the present study was to assess the clinical significance of prostate-specific antigen doubling time (PSADT) prior to and following radical prostatectomy. In total, 488 patients with T1c-3N0M0 prostate cancer who underwent radical prostatectomy were included. Preoperative and postoperative PSADT were retrospectively correlated with pathological and clinical outcomes. Preoperative PSADT was measured in 204 of the 488 patients. In total, 16 out of 20 patients with a preoperative PSADT of >24 months had a cancer confined to the prostate compared with 105 of 184 patients with a PSADT of <24 months. The PSA non-recurrence rate at 5 years for patients with a preoperative PSADT of >24 months was significantly better compared with those with a preoperative PSADT of <24 months (P=0.011). Patients with a PSADT of >24 months and stable PSADT were associated with PSA recurrence following surgery, based on multivariate analysis. Postoperative PSADT was measured in 51 of 111 patients with PSA failure following surgery. Pathologically, 7 of 8 patients with a post-PSADT of >24 months had a cancer confined to the prostate compared with 14 of 43 patients with a post-PSADT of <24 months. These results suggest that patients with longer preoperative PSADTs appeared to have a favorable pathological result and a higher PSA non-recurrence rate compared with those with shorter preoperative PSADTs. A longer postoperative PSADT may facilitate the observation of patients with PSA recurrence without immediate secondary treatments.

Active surveillance with selective delayed intervention is the way to manage 'good-risk' prostate cancer

This review summarizes the case for active surveillance of 'good-risk' prostate cancer, with selective delayed intervention for rapid biochemical progression, assessed by rising prostate-specific antigen (PSA) levels or grade progression. The results of a large phase II trial using this approach are also reviewed. A prospective phase II study of active surveillance with selective delayed intervention was initiated in 1995. Patients were managed initially with surveillance; those who had a PSA doubling time (PSADT) of < or = 2 years, or grade progression on repeat biopsy, were offered radical intervention. The remaining patients were closely monitored. The cohort now consists of 299 patients with good-risk--or, in men over 70 years of age, intermediate-risk--prostate cancer. The median PSADT was 7 years, 42% had a PSADT > 10 years. The majority of patients remain on surveillance. At 8 years, overall actuarial survival was 85%, and disease-specific survival was 99%. To date, this study has shown that most men with 'good-risk' prostate cancer will die of unrelated causes. The approach of active surveillance with selective delayed intervention based on PSADT represents a practical compromise between radical therapy for all patients, which results in overtreatment for patients with indolent disease, and watchful waiting with palliative therapy only, which results in undertreatment for those with aggressive disease. The results at 8 years were favorable. Longer follow-up will be required if the study is to confirm the safety of this approach in men with a long life expectancy (> 15 years).

PROSTATE CANCER CHARACTERISTICS AND PROSTATE SPECIFIC ANTIGEN CHANGES IN SCREENING DETECTED PATIENTS INITIALLY TREATED WITH A WATCHFUL WAITING POLICY

PURPOSE

We evaluated prostate cancer (PCa) characteristics at diagnosis and changes in prostatic specific antigen (PSA) with time in males with screening detected PCa that was initially managed with a watchful waiting policy.

MATERIALS AND METHODS

Patients with histologically proven PCa and PSA less than 10 ng/ml were selected from the European Randomized Study of Screening for Prostate Cancer, section Rotterdam. The choice of initiating a watchful waiting policy was patient desire or physician advice. PSA slope and PSA doubling time (PSADT) were calculated in patients with 3 or more PSA tests results available.

RESULTS

A total of 191 patients were included. Mean age at diagnosis was 69 years and mean PSA was 3.9 ng/ml. Of the patients 92.6% had a Gleason score of 3 + 3 or lower, 133 had a followup of greater than 12 months (mean 40) and 35 (29.2%) had a negative PSA slope. Mean PSADT was 9.7 years (range 0.3 to 155) in 85 males with a positive PSA slope. During followup 30 patients changed therapy.

CONCLUSIONS

Watchful waiting remains a controversial prostate cancer treatment strategy. In select screening detected patients with PCa there appears to be a subgroup with stable or even decreasing PSA values with time. These males could profit from a watchful waiting policy with possible deferred treatment. Together with conventional tumor parameters at diagnosis PSADT and PSA slope during followup could be used to monitor tumor activity and possibly aid in determining the time of deferred treatment. Further followup is mandatory to validate these results.

Predictors of Delayed Therapy after Expectant Management for Localized Prostate Cancer in the Era of Prostate-Specific Antigen

OBJECTIVE

To identify risk factors for delayed cancer-directed intervention in modern era prostate cancer patients who initially elect expectant management.

MATERIALS AND METHODS

An observational, cohort study of expectantly managed patients, diagnosed with clinical T(1-4)NxM0 prostate cancer between 1993 and 2000 was carried out. Data including TNM stage, age, serum prostate-specific antigen (PSA), prostate gland volume by transrectal ultrasound, Gleason score, percent biopsies positive for cancer, imaging results, initial treatment selection, and outcome data were collected on all patients.

RESULTS

192 of 561 patients (34.3%) elected expectant management, and follow-up data were available for 187 (97.4%) patients. With a median follow-up of 3.6 years, 90 (48.1%) patients had a cancer-directed intervention. Gleason score (p = 0.0097) and percent of positive biopsy cores (p = 0.03) were independent predictors of time to intervention. As expected, PSA doubling time became the most significant predictor of intervention (p = 0.0057) when added to the model. These independent covariates are able to characterize low-, intermediate- and high-risk groups for cancer-directed intervention.

CONCLUSIONS

Cancer-directed intervention is common in patients who choose expectant management in the PSA era. Gleason score and percent of positive biopsy cores predict cancer-directed interventions, thus, these patients may be least suitable for expectant management.

Impact of biochemical failure on long-term clinical outcome after radical prostatectomy for prostate cancer in Japan

Detailed information is needed to understand the impact of biochemical failure (bF) on long-term outcome after definitive therapy for prostate cancer. In all, 223 consecutive men treated with radical retropubic prostatectomy were followed and long-term clinical outcome was investigated. Pathological examination revealed more locally advanced tumors in this study compared with the typical cohorts seen in the Western series. The Cox proportional hazards model indicates pretreatment prostate-specific antigen levels and risk group stratification to be a significant predictors for bF (P<0.05), but not for overall survival. Seminal vesicle involvement was a significant predictor of systemic progression, cancer death and overall survival (P<0.05). Positive surgical margin and bF were also found to be independent predictors of overall survival (P<0.05). In contrast to reports from Western countries, this study found a significant correlation between bF after radical prostatectomy and overall survival. This may reflect years-later detection of prostate cancer in Japan compared with Western series. Biochemical failure may ultimately be translated into decreased overall survival after sufficient follow-up.

Temporarily Deferred Therapy (watchful waiting) for Men Younger Than 70 Years and With Low-Risk Localized Prostate Cancer in the Prostate-Specific Antigen Era

Purpose: Watchful waiting (WW) is an acceptable strategy for managing prostate cancer (PC) in older men. Prostate-specific antigen (PSA) testing has resulted in a stage migration, with diagnoses made in younger men. An analysis of the Department of Defense Center for Prostate Disease Research Database was undertaken to document younger men with low- or intermediate-grade PC who initially chose WW.

Patients and Methods: We identified men choosing WW who were diagnosed between January 1991 and January 2002, were 70 years or younger, had a Gleason score ≤ 6 with no Gleason pattern 4, had no more than three positive cores on biopsy, and whose clinical stage was ≤ T2 and PSA level was ≤ 20. We analyzed their likelihood of remaining on WW, the factors associated with secondary treatment, and the influence of comorbidities.

Results: Three hundred thirteen men were identified. Median follow-up time was 3.8 years. Median age was65.4 years (range, 41 to 70 years). Ninety-eight patients remained on WW; 215 proceeded to treatment. A total of 57.3% and 73.2% chose treatment within the first 2 and 4 years, respectively. Median PSA doubling time (DT) was 2.5 years for those who underwent therapy; those remaining on WW had a median DT of 25.8 years. The type of secondary treatment was associated with the number of patient’s comorbidities (P = .012).

Conclusion: Younger patients who choose WW seemed more likely to receive secondary treatment than older patients. PSA DTs often predict the use of secondary treatment. The number of comorbidities a patient has influences the type of secondary therapy chosen. The WW strategy may better be termed temporarily deferred therapy.

Anterior distribution of Stage T1c nonpalpable tumors in radical prostatectomy specimens

OBJECTIVES

To determine the anatomic patterns of tumor distribution in radical prostatectomy specimens from nonpalpable prostate cancer.

METHODS

Tumor maps directly traced from histologic slides of 62 radical prostatectomy specimens were superimposed by a computer-assisted imaging technique to create an idealized prostate gland at three levels: apex, mid-prostate, and base. To investigate specific patterns of tumor distribution, the sites of tumor in each quadrant were compared according to risk group stratification. The tumor extent was compared with the patterns of positivity in routine sextant biopsies.

RESULTS

Among all patients, the tumor frequency was 85.5% in the mid-gland, 82.3% in the apex, and 48.4% in the base. Analysis by quadrant showed that tumors were significantly denser in the apex to mid-prostate. The primary extent of these tumors appeared to lie predominantly in the anterior half of the gland. Biopsy yields at the apex and mid-prostate appeared low compared with the frequency of cancers at these levels. No patterns specific to the different risk groups were found, but no tumors within the anterior base were found in the low-risk group.

CONCLUSIONS

The primary extent of nonpalpable tumors appeared to lie predominantly in the anterior half of the gland at the apex to mid-prostate levels. Additional biopsy cores taken from more anterior regions of the gland may enhance the detection of nonpalpable cancers further.

Utility of PSA doubling time in follow-up of untreated patients with localized prostate cancer

OBJECTIVES

To evaluate the prostate-specific antigen (PSA) changes and the ability of PSA doubling time (PSADT) to predict disease progression in untreated patients with clinically localized prostate cancer.

METHODS

A total of 104 patients with localized prostate cancer were followed up expectantly with serial PSA measurements and digital rectal examination (DRE). PSADT was calculated by linear regression analysis for the 94 patients who had a minimum of three PSA measurements and 12 months of follow-up. The median follow-up was 33 months. Of the 94 patients, 45 underwent repeat prostate biopsy to evaluate whether tumor progression occurred during the observation period.

RESULTS

Twenty-seven percent of patients had rapid PSADTs (less than 48 months). Only the presence of palpable disease on DRE correlated with a PSADT of less than 48 months (P <0.05). However, a PSADT of less than 120 months consistently correlated with disease progression on DRE and on repeat biopsy, as well as with the presence of clinically significant cancer. PSADT did not correlate with the Gleason score. Furthermore, patients with a PSADT of less than 48 months did not differ significantly from those with a PSADT of 48 to 120 months with regard to Gleason score, disease progression on DRE or on repeat biopsy, and the presence of significant cancer.

CONCLUSIONS

A PSADT of less than 120 months correlates with disease progression. However, its clinical utility remains limited to identify patients at risk of disease progression reliably.

The dynamics of prostate specific antigen during watchful waiting of prostate carcinoma: a study of 94 Japanese men

BACKGROUND

For the moment, there is uncertainty about the usefulness of early treatment of localized prostate carcinoma, uncertainty about whether some patients with early cancer can be managed expectantly, and uncertainty about how such patients might be recognized.

METHODS

The authors studied serial values of prostate specific antigen (PSA) in 94 Japanese men with diagnosed prostate carcinoma and who were managed by watchful waiting. Their median follow-up duration was 32 months (range, 1.6-118). The authors used a log-linear model to fit the values of PSA over time, and then they used the Cox survival model to relate the intercept (PSA amplitude) and slope (relative velocity) to observed local or systemic outcomes that were independent of PSA.

RESULTS

The authors found that the log-linear model fit the serial values of PSA during watchful waiting very well. Prostate specific antigen amplitude related significantly to T classification (P = 0.0006), but not to grade (P > 0.2), and the relative velocity related significantly to both T classification (P = 0.009) and to grade (P = 0.02). Although the T classification, histologic grade, and log(PSA) at diagnosis were associated significantly with time to outcome, the combination of amplitude and relative velocity provided more information. These 2 PSA parameters resulted in a higher model likelihood ratio, and their individual P values in the Cox model were 0.0005 and 0.005, respectively. With these two in the Cox model, T classification, grade, log(PSA), and PSA doubling time provided no further significant information.

CONCLUSIONS

A log-linear model seems to fit serial measurements of PSA during watchful waiting, and preliminary results suggest that both the amplitude and the relative velocity relate closely to clinical outcomes.

Medically and economically appropriate follow-up schedule for prostate cancer patients after radical prostatectomy

BACKGROUND

Our goal was to determine the optimal frequency and method of follow-up after radical prostatectomy to minimize medical cost without adversely affecting patients.

METHODS

Two hundred and twenty-one patients who underwent a radical prostatectomy with or without adjuvant androgen deprivation from 1989 to 1999 were selected for the study. Eighty percent of the patients received postoperative androgen deprivation. Tumor recurrence was strictly defined as detectable serum prostate specific antigen (PSA) and/or clinical findings such as local tumor detection or bone metastasis. Thirty of 221 patients experienced tumor recurrence. Risk of tumor recurrence, procedures for detection of recurrence, and PSA doubling time after biochemical failure were analyzed.

RESULTS

None of the 30 patients who were examined showed definitive local recurrence or metastatic sites on the imaging study at the time of initial PSA detection, and there were no observed recurrences in the absence of detectable serum PSA. In patients who showed elevated PSA within 12 months after radical prostatectomy, PSA levels rapidly increased with doubling times ranging from 1.2 to 13.7 months. Excluding those patients, the doubling time of PSA levels ranged from 2.8 to 31.5 months.

CONCLUSIONS

Prostate specific antigen screening is sufficient to detect treatment failure after radical prostatectomy, irrespective of adjuvant hormone therapy. Based on the calculated doubling time, the longest advisable interval between checks of PSA levels is estimated to be four months within the first year after radical prostatectomy, and biannually or annually thereafter. Continuously elevated PSA levels or clinical symptoms indicate surveys for local recurrences and distant metastases.

Correlation of initial PSA level and biopsy features with PSA-doubling time in early stage prostate cancers in Japanese men

OBJECTIVE

To distinguish good candidates for watchful waiting from those who need immediate treatment in localized prostate cancer.

METHODS

Prostate specific antigen (PSA)-doubling time (DT) was calculated by a log-linear regression model for 78 patients with clinically localized prostate cancer (T1c: 47, T2a: 6, T2b: 21, and T3: 4) under surveillance. Median observation period was 37.5 months. The first 1-year PSA-DT was compared with the overall PSA-DT in 41 patients who had been under surveillance for more than 3 years.

RESULTS

There was significant difference in the PSA-DT distribution between a pooled group of T1c and T2a and a group of T2b and T3 patients (median 58.8 versus 33.3 months, P = 0.0052). A combination of three parameters consisting of initial PSA level less than 10 ng/ml, WHO grade 1, one or two positive core per six to eight systematic biopsy cores with 50% or less cancer involvement significantly correlated with PSA-DT distribution in the T1c plus T2a group (P = 0.0034). The first year assessment of PSA-DT was identical to the overall assessment in 48.8%, 2 years or more in 36.6%, while it was 2 years or less (possibly over-estimated) in 14.6%.

CONCLUSION

PSA-DT can be predictable to some extent with the initial PSA level and biopsy features in early stage prostate cancers. Prospective study is needed to clarify whether temporary observation together with PSA-DT estimation is a safe strategy and is complementary to clinico-pathological parameters at diagnosis.

The role of volume-weighted mean nuclear volume in predicting tumour biology and clinical behaviour in patients with prostate cancer undergoing watchful waiting

OBJECTIVE

To investigate whether the volume-weighted mean nuclear volume (MNV, the only means by which unbiased estimates of three-dimensional variables can be obtained from a two-dimensional section by stereological methods) at diagnosis correlates with tumour biology and clinical behaviour in patients with prostate cancer treated by watchful waiting.

PATIENTS AND METHODS

In a prognostic study, 64 patients with clinically localized prostate cancer were followed prospectively with initial expectant management. The median (mean, range) follow-up was 22 (27, 6.0-68) months. The prostate specific antigen (PSA) doubling time (PSADT) was calculated by linear regression. The MNV was estimated using biopsy specimens, based on a stereological method, and compared with PSADT and traditional clinicopathological variables.

RESULTS

PSADT was significantly associated with MNV, but not with other clinicopathological variables. The PSA 'rapid-riser' subset (PSADT<median value) had significantly larger MNVs than did the PSA 'slow-riser' (PSADT>or=median value) and PSA-stable subsets (P = 0.0017 and 0.004, respectively). On multivariate analysis using a stepwise Cox proportional hazards regression, only MNV remained independently significant as a predictor of clinical progression among the clinicopathological variables (P < 0.001).

CONCLUSIONS

These findings suggest that cancer cell nuclear volume is significantly associated with tumour biology and behaviour in patients with prostate cancer. Although further study with a larger patient population is needed to confirm the findings, estimates of MNV may be an important prognostic indicator in men treated with watchful waiting.

PSA doubling time of prostate carcinoma managed with watchful observation alone

PURPOSE

To study prostate-specific antigen (PSA) doubling time of untreated, favorable grade, prostate carcinoma.

METHODS AND MATERIALS

A prospective single-arm cohort study has been in progress to assess the feasibility of a watchful observation protocol with selective delayed intervention using clinical, histologic, or PSA progression as treatment indication in untreated, localized, favorable grade prostate adenocarcinoma (T1b-T2bN0 M0, Gleason Score < or = 7, and PSA < or = 15 ng/mL). Patients are conservatively managed with watchful observation alone, as long as they do not meet the arbitrarily defined disease progression criteria. Patients are followed regularly and undergo blood tests including PSA at each visit. PSA doubling time (Td) is estimated from a linear regression of ln(PSA) on time, assuming a simple exponential growth model.

RESULTS

As of March 2000, 134 patients have been on the study for a minimum of 12 months (median, 24; range, 12-52) and have a median frequency of PSA measurement of 7 times (range, 3-15). Median age is 70 years. Median PSA at enrollment is 6.3 (range, 0.5-14.6). The distribution of Td is as follows: <2 years, 19 patients; 2-5 years, 46; 5-10 years, 25; 10-20 years, 11; 20-50 years, 6; > 50 years, 27. The median Td is 5.1 years. In 44 patients (33%), Td is greater than 10 years. There was no correlation between Td and patient age, clinical T stage, Gleason score, or initial PSA level.

CONCLUSION

Td of untreated prostate cancer varies widely. In our cohort, 33% have Td > 10 years. Td may be a useful tool to guide treatment intervention for patients managed conservatively with watchful observation alone.

Preoperative PSA velocity and doubling time do not predict adverse pathologic features or biochemical recurrence after radical prostatectomy

OBJECTIVES

To improve the accuracy of predicting pathologic stage and biochemical recurrence after radical prostatectomy (RP), we sought to determine whether preoperative prostate-specific antigen (PSA) velocity and doubling time predict adverse pathologic features or biochemical recurrence following RP. We also sought to determine if there were racial differences in preoperative PSA velocity and doubling time.

METHODS

A total of 331 patients underwent RP at the West Los Angeles VA Medical Center between November 1991 and March 2000. Of these patients, 86 had two or more preoperative PSA values that were at least 12 months apart. Patients were analyzed to determine whether preoperative PSA velocity or doubling time was predictive of adverse pathologic features, including positive surgical margins, capsular penetration, seminal vesicle invasion, or biochemical recurrence. Additionally, PSA velocity and doubling time were compared among white, black, Hispanic, and Asian men.

RESULTS

Preoperative PSA velocity and doubling time were not predictive of positive surgical margins, capsular penetration, or seminal vesicle invasion (P >0.30). In addition, there was no association between PSA velocity or doubling time and pathologic stage or surgical Gleason score (P >0.36). Preoperative PSA velocity (P = 0.581) and doubling time (P = 0.528) were not predictors of biochemical recurrence following RP. There were no racial differences in preoperative PSA velocity (P = 0.715) or doubling time (P = 0.662).

CONCLUSIONS

Neither preoperative PSA velocity nor doubling time was a predictor of adverse pathologic findings or biochemical recurrence after RP. In addition, there was no difference in PSA velocity or doubling time between the races studied.