Adjuvant estrogen following radiation therapy for stage C adenocarcinoma of the prostate: long-term results of a prospective randomized study

A structured debate: immediate versus deferred androgen suppression in prostate cancer-evidence for deferred treatment

PURPOSE

We present a structured debate supporting the premise that immediate hormonal intervention has not been conclusively shown to provide a survival advantage in the management of advanced prostate cancer.

MATERIALS AND METHODS

The literature emphasizing randomized trials was reviewed. Recommendations are based solely on a demonstrated advantage in survival.

RESULTS

In patients with stage Tx Nx Mo or MI disease who did not receive other primary therapy there is no demonstrated survival advantage to immediate hormonal therapy. In men with positive lymph nodes who underwent radical prostatectomy a relatively small study showed a survival advantage in favor of immediate hormonal treatment compared to deferred treatment. This study did not reach the projected accrual of 240 patients and results have not been supported by other trials. In men with stages T2-4 Nx Mx disease who underwent primary treatment with radiotherapy a survival advantage for early hormonal therapy is primarily limited to high risk subgroups. In patients with biochemical relapse following primary treatment there are no trials.

CONCLUSIONS

Because hormonal therapy is associated with the development of irreversible resistance in virtually all patients, it does not cure, there is usually a long interval from first prostate specific antigen elevation to the development of metastatic disease, and hormonal therapy has profound side effects and is expensive, delayed treatment is recommended in men with biochemical relapse following surgery or radiotherapy. Patients should be strongly encouraged to enter clinical trials to answer this question.

Annual report to the nation on the status of cancer (1973 through 1998), featuring cancers with recent increasing trends

BACKGROUND

The American Cancer Society, the National Cancer Institute (NCI), the North American Association of Central Cancer Registries, and the Centers for Disease Control and Prevention, including the National Center for Health Statistics (NCHS), collaborate to provide an annual update on cancer occurrence and trends in the United States. This year's report contains a special feature that focuses on cancers with recent increasing trends.

METHODS

From 1992 through 1998, age-adjusted rates and annual percent changes are calculated for cancer incidence and underlying cause of death with the use of NCI incidence and NCHS mortality data. Joinpoint analysis, a model of joined line segments, is used to examine long-term trends for the four most common cancers and for those cancers with recent increasing trends in incidence or mortality. Statistically significant findings are based on a P value of.05 by use of a two-sided test. State-specific incidence and death rates for 1994 through 1998 are reported for major cancers.

RESULTS

From 1992 through 1998, total cancer death rates declined in males and females, while cancer incidence rates declined only in males. Incidence rates in females increased slightly, largely because of breast cancer increases that occurred in some older age groups, possibly as a result of increased early detection. Female lung cancer mortality, a major cause of death in women, continued to increase but more slowly than in earlier years. In addition, the incidence or mortality rate increased in 10 other sites, accounting for about 13% of total cancer incidence and mortality in the United States.

CONCLUSIONS

Overall cancer incidence and death rates continued to decline in the United States. Future progress will require sustained improvements in cancer prevention, screening, and treatment.

The 1989 patterns of care study for prostate cancer: five-year outcomes

PURPOSE

Five-year results from the 1989 patterns of care study (PCS) for prostate cancer are now ready for analysis. The PCS was initiated to determine national averages for treatments and examine outcomes prospectively; the 1989 prostate study is the first to have collected pre- and post-treatment serum PSA data.

METHODS AND MATERIALS

Six hundred patients treated with radiotherapy with curative intent for prostate cancer at 71 separate institutions in the year 1989 made up the study population. Three hundred ninety-one cases were fully analyzable. Pretreatment patient and tumor characteristics were as follows: of the 391 analyzable, 255 had pretreatment PSA values obtained, and 245 had a Gleason's sum (GS) reported. Three hundred fifty-eight were Caucasian, 24 African-American, and 3 Hispanic (also 6 unknown). One hundred three patients had PSA < 10, 60 had PSA 10-19, and 92 presented with PSA >20. Ninety-seven patients were from Radiation Therapy Oncology Group (RTOG), Community Cancer Centers (CCC), or teaching institutions; 141 patients were from other hospital-based, nonteaching institutions; and 153 were from freestanding radiation oncology facilities. Seventy-one patients were T1, 203 T2, and 100 T3/4. Twenty-four out of 391 patients also received neoadjuvant hormone therapy. Survival curves were constructed using Kaplan-Meier methods, and differences between groups were tested for significance using the log-rank test. For cumulative incidence curves, Gray's test was used to investigate failure distributions between groups. The variables entering Cox model for multivariate analysis included age, race, T stage, pretreatment PSA, and GS. A patient was considered a PSA failure if the treating radiation oncologist reported it as such.

RESULTS

With a median follow-up of 5.7 years, the 5-year biochemical no evidence of disease (bNED) and overall survival were 56% and 79% respectively for Stage T1, 52% and 81% for T2, and 36% and 63% for Stages T3 and T4 combined. As expected, higher pretreatment PSA, GS, and T stage were all prognostic of poorer outcome. On univariate analysis, bNED survival was adversely impacted by T stage (p = 0.009), pretreatment PSA (p = 0.0035), and by the GS (p = 0.0038). Cause-specific failure was significantly lower for higher T stage (p = 0.014), GS (p = 0.001), and also pretreatment PSA (p = 0.0004). Overall survival was significantly lower in patients with higher T stage (p = 0.047) or GS (p = 0.0191), but not pretreatment PSA (p = 0.284). On multivariate analysis, pretreatment PSA was found to be statistically significant in association with bNED survival, and GS was associated with overall survival, cause-specific survival, and distant metastasis. Few late complications were reported: 13/391 and 13/391 Grade 2-3 gastrointestinal (GI) and genitourinary (GU) complications respectively, with two patients having required surgery with or without a permanent colostomy.

CONCLUSION

For a representative cross-section of institutions in the United States, radiotherapy achieved high rates of bNED and CSS in selected groups of prostate cancer patients. When studied retrospectively, increased pretreatment PSA was a strong predictor of both biochemical failure and death due to prostate cancer. New strategies for patients with high-stage, high-grade tumors and/or pretreatment PSA >20 deserve testing.

Incidence rate and management of prostate carcinoma

The age-standardised incidence of prostate cancer varies more than one hundredfold between the areas with the highest and lowest incidences in the world. In certain areas, in particular the Western countries, the incidence has increased rapidly over the last 20 years. There are several environmental and genetic factors which partly explain these variations, although the incidence probably depends most of all on the extent to which small latent tumours are detected. As the clinical significance of small tumours is uncertain, the value of early diagnosis and early aggressive treatment is controversial. Randomised trials addressing this question have been initiated and will hopefully provide more evidence-based data in a decade from now. Small localised tumours are managed by radical surgery or radiation therapy. In elderly men or men unfit for operation or radiation therapy surveillance is often preferred. For advanced or metastatic prostate cancers androgen deprivation has been the mainstay of treatment since the early 1940s. Recently, several new treatment strategies have evolved but have not yet been introduced into clinical routine.

The external radiotherapy with three-dimensional conformal boost after the neoadjuvant androgen suppression for patients with locally advanced prostatic carcinoma

PURPOSE

To analyze the results in patients with locally advanced prostatic carcinoma treated by hormonal therapy followed by external radiotherapy using three-dimensional conformal radiation therapy (3D-CRT) boost.

METHODS AND MATERIALS

From 1987 to 1995, 46 patients with histologically proven locally advanced adenocarcinoma of the prostate were treated with 3D-CRT at the National Cancer Center Hospital, Tokyo. The neoadjuvant androgen suppression started immediately after the diagnosis followed by radical radiation therapy, according to the prospective protocol. They were treated with photons of 6-14 MV for wide fields and the boost, of which a multiple-leaf collimator of 2-cm width was available. The boosted dose was delivered with the rotational 3D-CRT, after the delivery of whole pelvis 4-field box from a dose of 40-46 Gy up to 66 Gy. The planning target volume encompassed 1 cm outside throughout the clinical target volume, and the prostate and the seminal vesicles were included in the boost field.

RESULTS

The 3D-CRT boost treatment completed as planned in all 46 patients. The median follow-up for all the patients was 60 months (range, 5-120 months). Nineteen of 46 patients died. Of these, 11 patients died of the intercurrent diseases. For all 46 patients, the 5- and 8-year overall survival rates were 61.3% and 42.4%, and the 5- and 8-year cause-specific survival rates were 82.4% and 64.4%, respectively. The prostate-specific antigen (PSA) relapse-free rates for 5- and 8-year were 64.6% and 52.5%, and the clinical local control rates for 5 and 8 years were 75.3% and 69.9%, respectively. The preradiation therapy PSA and the Gleason score were the factors that significantly associated with PSA relapse-free survival. Sixteen of 46 patients (35%) showed at least one form of late toxicities. Of these, 3 patients experienced late complications of Grade 3 (urinary, 2, proctitis, 1).

CONCLUSION

The treatment results were fairly good and were consistent with those in Western countries, indicating that this study shows the preliminary status of 3D-CRT for the locally advanced prostate cancer in Japan. Preradiation therapy PSA seems to be a significant predictor of PSA relapse-free survival (p = 0.004) after neoadjuvant androgen suppression.

Immediate hormonal therapy compared with observation after radical prostatectomy and pelvic lymphadenectomy in men with node-positive prostate cancer

BACKGROUND

Because the optimal timing of the institution of antiandrogen therapy for prostate cancer is controversial, we compared immediate and delayed treatment in patients who had minimal residual disease after radical prostatectomy.

METHODS

Ninety-eight men who underwent radical prostatectomy and pelvic lymphadenectomy and who were found to have nodal metastases were randomly assigned to receive immediate antiandrogen therapy, with either goserelin, a synthetic agonist of gonadotropin-releasing hormone, or bilateral orchiectomy, or to be followed until disease progression. The patients were assessed quarterly during the first year and then semiannually.

RESULTS

After a median of 7.1 years of follow-up, 7 of 47 men who received immediate antiandrogen treatment had died, as compared with 18 of 51 men in the observation group (P=0.02). The cause of death was prostate cancer in 3 men in the immediate-treatment group and in 16 men in the observation group (P<0.01). At the time of the last follow-up, 36 men in the immediate-treatment group (77 percent) and 9 men in the observation group (18 percent) were alive and had no evidence of recurrent disease, including undetectable serum prostate-specific antigen levels (P<0.001). In the observation group, the disease recurred in 42 men; 13 of the 36 who were treated had a complete response to local treatment or hormonal therapy (or both), 16 died of prostate cancer, and 1 died of another disease. The remaining men in this group were alive with progressive disease at the time of the last follow-up or had had a recent relapse. Except for the treatment group (immediate therapy or observation), no clinical or histologic characteristic significantly influenced the outcome.

CONCLUSIONS

Immediate antiandrogen therapy after radical prostatectomy and pelvic lymphadenectomy improves survival and reduces the risk of recurrence in patients with node-positive prostate cancer.

Is there a role for short-term hormone use in the treatment of nonmetastatic prostate cancer?

We reviewed our institution's experience treating patients with prostate cancer with 3-dimensional conformal radiation therapy (3DCRT) and short-term adjuvant hormonal therapy to determine biochemical no evidence of disease (bNED) and clinical outcome compared with patients treated with 3DCRT alone. Between 4/1/89 and 11/30/94, 558 patients with clinically localized prostate cancer received treatment at Fox Chase Cancer Center (Philadelphia, Pa.); 484 patients were treated with 3DCRT alone (Group I); 74 patients were treated with 3DCRT and hormones (Group II). Five-year actuarial rates of bNED control, distant metastasis-free survival (DMFS), cause-specific survival (CSS), and overall survival (OS) were calculated for pretreatment PSA, Gleason score, T stage, use of hormones, treatment field size, age, and dose. A matched case/control analysis was performed to further evaluate the effect of hormones on treatment with 3DCRT. Median follow-up was 47 months (range: 2-97 months). The 5-year actuarial rates of bNED control, DMFS, CSS, and OS were 66%, 93%, 98%, and 86%, respectively, for Group I patients and 68%, 93%, 98%, and 89%, respectively, for Group II patients. Multivariate analysis demonstrated that hormone use was an independent predictor of bNED control only. A significant difference in bNED control was observed between Group I and II (43% vs. 71%) using the matched case/control analysis (P = 0.02). A trend towards significance was observed for different rates of DMFS between Group I and II (79% vs. 94%, P = 0.09). Patients with clinically localized prostate cancer with poor prognostic features (pretreatment PSA > or = 10 ng/ml, Gleason score > or = 7, and/or T2c or greater palpation stage) show improved rates of bNED control and a trend towards improved DMFS when treated with 3DCRT and short-term adjuvant hormones compared with 3DCRT alone. Long-term observation will be necessary to see if improvements in bNED control will translate into improvements in overall survival.

Patient selection for salvage cryotherapy for locally recurrent prostate cancer after radiation therapy

PURPOSE

Our objective was to identify clinical pretreatment factors associated with early treatment failure after salvage cryotherapy.

PATIENTS AND METHODS

Between 1992 and 1995, 145 patients underwent salvage cryotherapy for locally recurrent adenocarcinoma of the prostate. Treatment failure was defined as an increasing postcryotherapy serial prostate-specific antigen (PSA) level of more than or equal to 2 ng/mL above the postcryotherapy nadir or as a positive posttreatment biopsy. We evaluated the following factors as predictors of treatment failure: tumor stage and grade at initial diagnosis, type of prior therapy, stage and grade of locally recurrent tumor, number of positive biopsy cores at recurrence, and precryotherapy PSA level.

RESULTS

Among patients with a prior history of radiation therapy only, the 2-year actuarial disease-free survival (DFS) rates were 74% for patients with a precryotherapy PSA less than 10 ng/mL and 28% for patients with a precryotherapy PSA more than 10 ng/mL, P <.00001. The DFS rates were 58% for patients with a Gleason score of less than or equal to 8 recurrence and 29% for patients with a Gleason score greater than or equal to 9 recurrence, P <.004. Among patients with a precryotherapy PSA less than 10 ng/mL, DFS rates were 74% for patients with a prior history of radiation therapy only and 19% for patients with a history of prior hormonal therapy plus radiation therapy, P <.002.

CONCLUSION

Patients failing initial radiation therapy with a PSA more than 10 ng/mL and Gleason score of the recurrent cancer more than or equal to 9 are unlikely to be successfully salvaged. Patients failing initial hormonal therapy and radiation therapy are less likely to be successfully salvaged than patients failing radiation therapy only.

Recent advances in the treatment of prostate cancer

As new evidence for prostate cancer treatment has emerged in the last few years, longstanding controversies in the treatment of prostate cancer have resurfaced. A number of long-held tenets of prostate cancer therapy have been revisited, sometimes with surprising and challenging results. Although neoadjuvant hormonal therapy prior to radical prostatectomy decreases positive surgical margin rates, longer follow-up is needed to support survival improvement of this combined modality therapy. Androgen deprivation combined with radiation therapy appears to improve disease-free survival (and survival in one series) in patients with locally advanced cancer. Another approach to locally advanced prostate cancer using three-dimensional conformal radiation therapy may improve long term outcome. The data are currently insufficient to conclude that interstitial low dose rate brachytherapy is equivalent to conventional treatments: patients with small tumor volumes and low Gleason grade seem to obtain more benefit, whereas for large tumors with higher gleason grades this approach seems inferior to conventional treatments. In advanced prostate cancer recent data suggest that immediate hormonal therapy improves survival. In this group of patients the use of maximum androgen blockade remains controversial but may adversely affect quality of life compared to orchiectomy alone. Intermittent hormonal therapy may improve quality of life, although effect upon survival is unknown. Chemotherapy in combination with androgen deprivation is currently being studied as front-line therapy in advanced prostate cancer. Palliative benefit of chemotherapy for hormone refractory prostate cancer remains an important endpoint; survival advantage has not been seen in any randomized trials. Suramin may delay disease progression in hormone refractory prostate cancer. Many aspects of prostate cancer treatment will remain controversial until results of large, randomized trials with longer follow-up are available.

Conventional external-beam radiation therapy alone or with androgen ablation for clinical stage III (T3, NX/N0, M0) adenocarcinoma of the prostate

PURPOSE

To evaluate the outcome of clinical Stage III (T3, N0/NX, M0) prostate cancer treated by conventional radiation alone or with adjuvant androgen ablation.

METHODS AND MATERIALS

Three hundred forty-four men with T3, N0/NX, M0 adenocarcinoma of the prostate who received conventional radiation alone (260) or with androgen ablation (84) were analyzed for relapse or rising prostate-specific antigen (PSA), using univariate and multivariate techniques.

RESULTS

With a median follow-up of 68 months, the 260 men treated with radiation alone had a 10-year actuarial rate of relapse or rising PSA of 76%. Pretreatment PSA level (< or = 10 ng/ml vs. > 10 < or = 20 ng/ml vs. > 20 ng/ml) and radiation dose (< 68 Gy vs. > or = 68 Gy) were the only independently significant determinants of biochemical failure; Gleason score (2-7 vs. 8-10) was an additional determinant of metastatic relapse. Patients treated to doses < 68 Gy experienced 6-year failure rates exceeding 50% regardless of PSA level. Patients with PSA < or = 10 ng/ml and receiving 68-70 Gy had a 6-year failure of 24%, but those with PSA > 10 ng/ml had relapse rates exceeding 50% even at doses of 70 Gy. At a median follow-up of 44 months, the 84 patients treated with radiation and androgen ablation had a 6-year biochemical failure rate of 22%. The only significant determinant of outcome in this group was pretreatment PSA; patients with PSA < or = 80 ng/ml had a 6-year failure rate of only 12% compared to a failure rate of 53% for those with PSA > 80 ng/ml. The outcome for those treated with combined modalities was significantly better than for those treated with radiation alone in all PSA strata.

CONCLUSION

Conventional radiation alone has little curative potential for Stage III disease. Doses < 68 Gy are particularly ineffective. Patients with PSA < or = 10 ng/ml may be candidates for conventional radiation to a dose of 70 Gy. Other patients are probably best served by combined radiation-androgen ablation or high-dose conformal radiation.

The role of androgen deprivation in the definitive management of clinically localized prostate cancer treated with radiation therapy

PURPOSE

Multiple studies exploring the use of androgen deprivation given in combination with radiotherapy (RT) for localized prostate cancer have reported significant improvements in the rates of local, regional, and biochemical control (BC). The impact of this therapeutic strategy on overall and cancer specific survival (CSS) has not been established, however. We performed a MEDLINE search of all available studies on this topic to determine if any conclusions could be reached on the efficacy of this treatment approach and the patients most suitable for its application.

MATERIALS AND METHODS

A MEDLINE search was conducted to obtain all articles in the English language on the use of androgen deprivation in combination with RT for the treatment of localized prostate cancer. The medical subject headings (MeSH) used to search the MEDLINE database included: a) prostatic neoplasms; b) prostatic neoplasms/radiotherapy; c) prostatic neoplasms/androgen deprivation; d) hormone therapy; e) English; and f) 1980 to 1998.

RESULTS

A total of 14 retrospective studies were identified that compared some form of androgen deprivation given in combination with RT. Most studies showed significant improvements in various measures of local/regional control and disease-free survival (DFS). Three of four studies that analyzed BC rates showed significant improvements in this endpoint but conflicting results were obtained for overall survival (OS). No study showed an improvement in CSS. Six prospective randomized trials were identified that directly compared RT with or without androgen deprivation. Again, all six studies showed improvements in some measure of local/regional control or DFS but only two studies showed an improvement in OS. One study reported a statistically significant improvement in CSS and another study showed an improvement in the rate of negative biopsies with combined treatment.

CONCLUSIONS

When all available literature on androgen withdrawal given in combination with RT for the definitive treatment of localized prostate cancer was reviewed, no definite conclusions could be reached on the impact of this treatment approach on OS and CSS. However, local/regional control, DFS, and BC were almost uniformly improved with the use of androgen withdrawal suggesting that these impressive early results may translate into improved cure rates. Data from recently initiated and completed randomized trials will be needed, however, to define the impact of this approach on cancer specific mortality and the patients most suitable for it's use.

The current status of adjuvant hormonal therapy combined with radiation therapy for localised prostate cancer

Analysis of the results of treatment of localised prostate cancer with radiation and surgery has identified patients who are at high risk of developing metastatic dissemination. High histologic grade, serum prostate specific antigen above 20 ng/ml, extension beyond the capsule of the prostate, and involvement of lymph nodes are highly predictive of metastatic risk. Antiandrogen therapy has high rates of activity in the treatment of overt metastatic disease prompting its assessment as an adjuvant treatment added to radiation therapy. There are now major prospective randomized trials which have been completed. The current evidence indicates that a large survival benefit ensues when antiandrogen therapy is added to radiation for appropriately selected patients. This adjuvant approach is likely to become the standard of care. Strategies for further enhancement of adjuvant therapy are discussed.

Radical radiotherapy of localised prostate cancer: the relationship between radiation dose and survival

PURPOSE

This retrospective study aims to define the effects of different radiation dose levels on survival, local control and toxicity in a series of 208 patients with localised prostate cancer consecutively treated with radical radiation therapy.

PATIENTS AND METHODS

From 1982 through 1996, 365 patients with prostate cancer have been consecutively treated with radical radiotherapy in Florence (n = 306) and Arezzo (n = 59). The 208 cases treated until January 1994 with Stage B (125/208, 60%) and C (83/208, 40%) are the objects of the present study. The treatment was most often limited to the prostatic area (81%), using a four-field "box technique" and 25 MV photon beams, up to a total dose of 60-65 Gy (21% of the patients), of 66-69 Gy (26%) and of 70 Gy (53%); conventional fractionation was used (fractional dose: 2 Gy; five fractions/week). Hormonal therapy was also given to 39% of the cases. The possible relationship between dose, stage, grading and survival has been analysed. The survival figures and the types of relapse observed (prostatic, lymphnodal or "biochemical") have been analysed also according to the extent of the target volume and to the prostate-specific antigen (PSA) value at diagnosis, in the entire series or in selected subgroups.

RESULTS

In the whole series and also after radiation alone, the patients with Stage B, with more differentiated tumours and those treated with higher doses to the prostate obtained significantly better survival results. Multivariate analysis confirmed that the dose level has an independent prognostic value. The use of a limited target volume did not produce an excess of pelvic lymphnodal failures. Among the patients more recently treated with radiation alone, the PSA level at diagnosis is strongly related with the risk of local and "biochemical" failure, and also with the relapse-free survival. Toxicity was acceptable, also for the patients treated with higher doses, but late treatment-related damage is more frequent in patients treated on larger volumes.

CONCLUSION

The results of this retrospective analysis confirm the good results of small volume, high dose radiation therapy of prostatic cancer, even taking into account the possible biases due to the retrospective nature of the study, and the relevance of the PSA level at diagnosis to define the risk of local failure.

Androgen ablation in addition to radiation therapy for prostate cancer: is there true benefit?

Prostate cancer patients may now be identified as having a high risk of failing single-modality treatment based on pretreatment prostate specific antigen (PSA), Gleason score, and palpable stage. In particular, a PSA greater than 20 ng/mL portends a biochemical failure rate of 50% to 80% when radiation therapy, surgery, or androgen ablation is administered individually. A number of randomized trials as well as retrospective data show that failure rates are significantly reduced by combining androgen ablation and radiation. The improved results, however, are complicated by the ability to salvage radiation alone-treated patients with androgen ablation and the possibility of less effective salvage (or no effective salvage in the case of permanent androgen ablation) for patients treated with androgen ablation plus radiation. Thus, survival, which is obscured by high rates of intercurrent deaths in this elderly population, is the most important end point in such studies. Two randomized trials, one from the Radiation Therapy Oncology Group (RTOG) and one from the European Organization for Research on Treatment for Cancer (EORTC), of radiation therapy plus adjuvant (as opposed to neoadjuvant) androgen ablation have reported survival gains over radiation therapy alone. In contrast, one neoadjuvant trial from the RTOG failed to show a survival benefit when androgen ablation was added to radiation therapy. In this study, however, androgen ablation was administered for only 4 to 5 months, which may be insufficient. The weight of the evidence to date indicates a true benefit with androgen ablation plus radiation therapy over radiation therapy alone. There are clearly many unanswered questions concerning the optimal timing of androgen ablation and radiation therapy (neoadjuvant versus adjuvant), length of time that androgen ablation should be administered (6 months versus 3 years versus permanent), type of androgen ablation (total androgen ablation or not), and appropriate patient population (definition of high risk). The planned future clinical trials will address many of these issues; however, the full potential of this approach requires an understanding of the fundamental mechanisms involved.

Predicting the outcome of radiotherapy for prostate carcinoma: a model-building strategy

BACKGROUND

Clinical research of prostate carcinoma could be enhanced by models that allow early and reliable prediction of outcome. In this study, the authors describe a model-building strategy and compare different models.

METHODS

The sample population was comprised of 158 patients treated definitively with radiotherapy. Univariate and multivariate logistic regression analyses were conducted to identify prognostic factors and select the best predictive model. Variables included age, race, method of diagnosis (needle biopsy vs. transurethral resection of the prostate), stage, grade, pretreatment prostate specific antigen (PSA), in-treatment PSA (PSA(tx)), posttreatment PSA (PSA(post)), and nadir PSA. The following indices were used to compare discriminatory power: log-likelihood function, Akaike information criterion, the generalized coefficient of determination, and the area under the receiver operating characteristic curve.

RESULTS

At last follow-up, 49 patients (31%) had recurrence of carcinoma. By univariate analysis, the failure rate was significantly higher in patients with advanced stage, higher grade, higher pretherapy PSA, and nadir PSA > 1 ng/mL (P < 0.0001). Pretherapy PSA was associated significantly with stage, age, and nadir PSA (P = 0.001, P = 0.001, and P = 0.001, respectively). All PSA measurements were significantly interrelated. Nadir PSA was the most predictive variable. Significant gains (P = 0.01) in predictive power were derived from inclusion of PSA(tx), but not PSA (post). Age, race, stage, grade, and method of diagnosis contributed predictive power in addition to that derived from PSA levels (P = 0.01, log-likelihood test). The authors' model of choice predicts outcome with an overall correctness, sensitivity, specificity, and false-negative rate of 81.8%, 87.2%, 79.6%, and 12.8%, respectively.

CONCLUSIONS

Applying the strategy described, a model was selected that allowed accurate prediction of failure shortly after the completion of therapy.

Radiotherapy with or without androgen deprivation in the treatment of localized adenocarcinoma of the prostate

This study analyzes the results of disease relapse and survival in two series of patients treated between 1974 and 1991 with definitive irradiation, with or without early androgen deprivation, for carcinoma of the prostate localized to the pelvis. All 264 patients were irradiated to the prostate and pelvic lymph nodes with a dose of 50 to 54 Gy in 25 to 27 fractions, followed by a 16- to 20-Gy boost in 8 to 10 fractions to the prostate and periprostatic region. Ninety percent of patients received a total dose to the prostate (pelvis + boost) of 70 Gy. Ninety-nine of the 264 patients underwent early androgen deprivation. The endocrine manipulation program was initiated 0 to 9 months before the beginning of the radiotherapy course and was continued for 2 or more years or until disease progression. All patients who relapsed after radiotherapy alone received late hormonal manipulation. After a median follow-up of 100 months, no difference in the incidence of local and distant failure rate and cancer-specific mortality was detected between the two treatment groups. The local and distant failure rates were, respectively, 19% and 40% in patients who had undergone radiotherapy and early androgen deprivation and 20% and 36% in patients who received radiotherapy alone. Cancer mortality was similar, with 35% and 30% of deaths in the former and latter group, respectively. Death for intercurrent disease, however, was significantly more frequent (p = 0.03) in patients treated with radiotherapy and hormones (19%) than in those who received radiotherapy alone (8%). Actuarial analysis of both metastasis-free and disease-free survival detected no difference between the two treatment groups, with 10-year rates of 53.3% and 42.5%, respectively, in the radiation-alone group and 45.5% and 47%, respectively, in the radiation-plus-androgen deprivation group. A statistically significant difference (p = 0.03) in overall survival in favor of patients treated with radiotherapy alone was noted, with a 10-year rate of 47%, compared with 26% observed in the radiotherapy-plus-androgen deprivation group. In conclusion, results of our study confirm numerous reports based on retrospective analyses that failed to show any benefit of hormonal management adjuvant to a definitive irradiation. The disappointing finding was the significantly better overall survival in patients who underwent radiotherapy alone.

Prostate cancer patient subsets showing improved bNED control with adjuvant androgen deprivation

PURPOSE

Cooperative groups have investigated the outcome of androgen deprivation therapy combined with radiation therapy in prostate cancer patients with variable pretreatment prognostic indicators. This report describes an objective means of selecting patients for adjuvant hormonal therapy by a retrospective matched case/control comparison of outcome between patients with specific pretreatment characteristics who receive adjuvant hormones (RT+H) vs. patients with identical pretreatment characteristics treated with radiation therapy alone (RT). In addition, this report shows the 5-year bNED control for patients selected by this method for RT+H vs. RT alone.

METHODS AND MATERIALS

From 10/88 to 12/93, 517 T1-T3 NXM0 patients with known pretreatment PSA level were treated at Fox Chase Cancer Center. Four hundred fifty-nine of those patients were treated with RT alone while 58 were treated with RT+H. The patients were categorized according to putative prognostic factors indicative of bNED control, which include the palpation stage, Gleason score, and pretreatment PSA. We compared actuarial bNED control rates according to treatment group within each of the prognostic groups. In addition, we devised a retrospective matched case/control selection of RT patients for comparison with the RT+H group. Five-year bNED control was compared for the two treatment groups, excluding the best prognosis group, using 56 RT+H patients and 56 matched (by stage, grade, and pretreatment PSA level) controls randomly selected from the RT alone group. bNED control for the entire group of 517 patients was then analyzed multivariately using step-wise Cox regression to determine independent predictors of outcome. Covariates considered for entry into the model included stage (T1/T2AB vs. T2C/T3), grade (2-6 vs. 7-10), pretreatment PSA (0-15 vs. > 15), treatment (RT vs. RT+H), and center of prostate dose. bNED failure is defined as PSA > or = 1.5 ngm/ml and rising on two consecutive determinations. The median follow-up for the 112 matched case/control patients was 41 months. The median follow-up was 46 months for the RT (range 11-102 months) and 37 months for the RT+H group (range 6-82 months).

RESULTS

Univariate analysis according to treatment for the prognostic factors of palpation stage, Gleason score, and pretreatment PSA demonstrates a significant improvement in 3-year bNED control with the addition of hormones for patients with T2C/T3, Gleason score 7-10, or pretreatment PSA > 15 ngm/ml. A comparison of bNED control according to treatment demonstrates improvement in 5-year bNED control of 55% for patients treated with RT+H vs. 31% for those patients treated with RT alone (p = 0.0088), although there is not a survival advantage. Multivariate analysis demonstrates that hormonal treatment is a highly significant independent predictor of bNED control (p = 0.0006) along with pretreatment PSA (p = 0.0001), palpation stage (p = 0.0001), grade (p = 0.0030), and dose (p = 0.0001).

CONCLUSIONS

(1) Patients with specific adverse pretreatment prognostic factors (i.e., T2C/T3, Gleason score 7-10, pretreatment PSA > 15) benefit from adjuvant hormonal therapy. (2) Upon multivariate analysis, hormonal therapy is determined to be a highly significant predictor of bNED control, after adjusting for all other covariates. (3) The 5-year bNED control rates of 55% for RT+H vs. 31% for RT alone represents the magnitude of benefit from adjuvant hormone therapy. (4) The bNED control curves are separated by about 20 months, representing a delay in disease progression with adjuvant hormonal therapy, as there is no overall survival difference.

Supraadditive apoptotic response of R3327-G rat prostate tumors to androgen ablation and radiation

PURPOSE

Androgen ablation is often combined with radiation in the treatment of patients with prostate cancer, yet, the optimal sequencing and the mechanisms governing the interaction are not understood. The objectives were to determine if cell killing via apoptosis is enhanced when the combined treatment is administered and to define the relationship of changes in this form of cell killing to tumor volume growth delay.

MATERIALS AND METHODS

Dunning R3327-G rat prostate tumors, grown in the flanks of Copenhagen rats, were used at a volume of approximately 1 cc. Androgen ablation was initiated by castration, and androgen restoration was achieved with 0.5 cm silastic tube implants containing testosterone. 60Co was used for irradiation. The terminal deoxynucleotidyl transferase (TUNEL) histochemical assay was used to quantify apoptosis.

RESULTS

Tumors from intact and castrate unirradiated control rats had average apoptotic indices (percent of apoptotic cells) of 0.4 and 1.0%, respectively. The apoptotic index varied only slightly over time (3 h to 28 days) after castration (range 0.75-1.43%). Irradiation of intact rats to 7 Gy resulted in a peak apoptotic response at 6 h of 2.3%. A supraadditive apoptotic response was seen when castration was initiated 3 days prior to 7 Gy radiation, with peak levels of about 10.1%. When the radiation was administered at increasing times beyond 3 days after castration, the apoptotic response gradually diminished and was back to levels seen in intact rats by 28 days after castration. Tumor volume growth delay studies were consistent with, but not conclusive proof of, a supraadditive effect when the combination was used.

DISCUSSION

A supraadditive apoptotic response was seen when androgen ablation and radiation were used to treat androgen sensitive R3327-G rat prostate tumors. This supraadditive effect was dependent on the timing of the two treatments. Further studies are required to more fully define the optimal timing and administration of androgen ablation and radiation.

Orchidectomy prior to definitive radiotherapy for localized prostatic cancer

PURPOSE

To identify potential survival benefits of cytoreductive orchidectomy performed prior to definitive radiation for localized prostate cancer.

METHODS AND MATERIALS

Between 1977-1988, all patients with localized prostatic cancer from the Wellington Region received definitive radiotherapy (n = 200). One referring urologist Peter M. Meffen (P.M.M.) had commenced a program of prior orchidectomy followed by definitive radiation treatment (median time to radiation therapy was 5 months, n = 30).

RESULTS

Five-year overall survival (OS) and relapse-free survival (RFS) for each stage were Stage A 82%, and 82%; Stage B 75%, and 61%; Stage C 57%, and 38%, respectively. Ten-year OS and RFS for each stage were Stage A 78%, and 72%; Stage B 51%, and 18%; Stage C 32% and 0%, respectively. Multivariate analysis identified prior orchidectomy treatment and histological grade as independently significant prognostic factors for OS and RFS. Factors influencing RFS were clinical stage, prior orchidectomy, and histological grade. Prior orchidectomy was associated with an increase in OS at 5 years when compared to those patients receiving radiotherapy alone, 86% vs. 69%, and maintained at 10 years, 82% vs. 46% (p < 0.05). The two groups were comparable by stage, histological grade, and age. There were no changes in the referral pattern during the study period.

CONCLUSIONS

Our results suggest that prior cytoreduction by orchidectomy has a beneficial effect on OS and RFS for patients with localized prostate cancer. It is unclear whether survival benefits are due to the cytoreductive therapy, the adjuvant therapy, or a combination of both. Further study in this area is warranted, ideally in the form of randomized prospective clinical trials.

Prostate cancer and radiation therapy--the message conveyed by serum prostate-specific antigen

PURPOSE

Prostate-specific antigen (PSA) is a powerful pretreatment prognosticator and a sensitive post-treatment outcome measure for clinically localized prostate cancer treated with radiation therapy. Today, the pretreatment serum PSA level appears to supersede both grade and T-stage as a determinant of outcome. This study was undertaken to attempt a reconciliation between the old (pre-PSA) and the new (PSA) data-in particular to address the question of why stage and grade apparently play so little role in this PSA era.

METHODS AND MATERIALS

We analyzed the outcome of two cohorts of men with T1-T4, NO, or NX, MO prostate cancer, one group (648 patients) treated and followed in the pre-PSA era (1966-1988), another group (707 patients) treated and followed in the PSA era (1987-1993)--who received definitive radiation as their only initial treatment. The patterns of relapse and prognostic factors for these groups were compared and contrasted using univariate and multivariate techniques.

RESULTS

At a median follow-up of 6.5 years, the relapse patterns in the pre-PSA series were: local in 109 (17%), nodal in 17 (3%), and distant metastatic in 186 (29%). Actuarial local and metastatic rates at 5 years were 13 and 26%, respectively. Local recurrence was only weakly predictable, Gleason grade being the only significant, albeit weak, covariate. Metastatic failure, however, was highly significantly and meaningfully correlated with Gleason grade and T-stage. Because metastasis was the most common adverse end point in this series, overall freedom from progression also correlated with grade and stage. At a median follow-up of 31 months, the patterns of failure in the PSA series were: local in 77 (11%), nodal in 3 (< 1%), and distant metastatic in 24 (3%). Actuarial local and metastatic rates at 5 years were 30 and 6%, respectively. Local recurrence was highly and meaningfully correlated with pretreatment PSA level, which was the only significant determinant of this end point. Metastatic failure was highly correlated with Gleason grade and T-stage, with PSA playing a much lesser, though significant role. The inversion of failure patterns (local vs. distant) between the two series was striking. The high incidence of local failure in the PSA series was almost entirely related to positive prostatic biopsies pursuant to the investigation of the postradiation rising PSA profile. Of the 77 local recurrences, 69 (90%) were identified in this way. Among 99 men with rising PSA values who underwent investigation (CT scans, bone scans, and biopsies), disease was found in 86, and the patterns of disease in these 86 were: local only in 62 (72%), local and metastatic in 7, and metastatic in 17 (20%). The most common event in the PSA series was the rising PSA profile, and this, too, strongly correlated with the pretreatment PSA level.

CONCLUSION

Based on our earlier finding that the major source of pretreatment serum PSA in patients with clinically localized disease is the primary tumour itself and on the findings in the present report, we conclude that the new major message conveyed by serum PSA relates to the primary tumor and its likely outcome. Gleason grade and T-stage remain major determinants of metastatic relapse. The total and permanent eradication of prostate cancer from the prostate with conventional doses of external beam radiation therapy is harder to achieve than generally appreciated.

Radiotherapy and androgen ablation for clinically localized high-risk prostate cancer

PURPOSE

The response of patients with clinical stages T1-4 prostate cancer to radiotherapy is variable. A particularly poor prognostic group has been found to be comprised of those with pretreatment prostate specific antigen (PSA) levels above 30 ng/ml with any tumor grade, or PSA levels > 10 and < or = 30 with tumors grade 3 or 4. These patients have over an 80% actuarial risk of biochemical failure 3 years after definitive external beam radiotherapy. Thus, patients with these high-risk features require more aggressive therapy. During the last 3-4 years, the policy to treat such patients with radiotherapy and androgen ablation (XRT/HORM) was instituted. A retrospective comparison was made between high-risk patients treated with radiotherapy alone (XRT) vs. XRT/HORM.

METHODS AND MATERIALS

Between 1987 and 1991, there were 81 high-risk patients treated with XRT. There were 38 high-risk patients treated with XRT/HORM between 1990 and 1992. The median follow-up was 37 months for the XRT group and 22 months for the XRT/HORM group. No patient had clinical, radiographic, or pathologic evidence of lymph node involvement. The median dose to the prostate was 66 Gy for the XRT group and 68 Gy for the XRT/HORM group.

RESULTS

The distributions of several potential prognostic factors were analyzed. Significant differences between the groups were observed for tumor grade, pretreatment prostatic acid phosphatase, and age. The XRT/HORM group was composed of patients with worse features, including a greater proportion of patients with grade 4 tumors, more with abnormal acid phosphatase levels, and more under 60 years of age. The actuarial incidence of a rising PSA at 3 years for the XRT group was 81% vs. 15% for the XRT/HORM group (p < 0.0001). In addition, local relapse at 3 years was 34% for the XRT group and 15% for the XRT/HORM group (p < 0.02). There was no difference between the groups in terms of survival. Cox proportional hazards analyses were performed using several disease end points, including a rising PSA, a rising PSA or disease relapse, any disease relapse, and local relapse, and the only prognostic factor of independent predictive value was treatment group, i.e., XRT vs. XRT/HORM.

CONCLUSIONS

Based on biochemical and disease relapse end points, definitive radiotherapy is insufficient treatment for high-risk prostate cancer patients. The addition of androgen ablation significantly reduces the recurrence rates, although longer follow-up is needed to determine if the combined treatment impacts significantly on survival.

Influence of radiotherapy on node-positive prostate cancer treated with androgen ablation

PURPOSE

Patients with node-positive prostate cancer that is regionally localized (T1-4, N1-3, M0) have a relatively poor prognosis when a single-treatment modality such as radical surgery, definitive radiotherapy, or androgen ablation is used. While promising results using radical surgery and androgen ablation have been reported, there are no data to support an analogous approach using local radiotherapy and androgen ablation. In this retrospective review, the outcome after local radiotherapy and early androgen ablation (XRT/HORM) was compared to early androgen ablation alone (HORM).

METHODS AND MATERIALS

Between 1984 and 1992 there were 181 patients treated with HORM and 27 patients treated with XRT/HORM at the University of Texas M. D. Anderson Cancer Center. The nodal status of all patients was established pathologically by lymph node dissection, which was terminated after frozen section confirmation of involvement. In the majority of cases androgen ablation was by orchiectomy. The median dose to the prostate in XRT/HORM group was 66 Gy. The median follow-up was 45 months; 49 months for the HORM group and 25 months for the XRT/HORM group.

RESULTS

The distribution of prognostic factors between the HORM and XRT/HORM groups was similar, with the exception of tumor grade. There was a significantly larger proportion of high grade tumors in the HORM group. In terms of actuarial disease outcome, at 4 years the results of patients in the HORM group were significantly worse, including a rising prostate specific antigen (PSA) of 53%, any disease progression of 32%, a rising PSA or disease progression of 55%, and local progression of 22%. None of the patients in the XRT/HORM group failed biochemically or clinically. To determine the impact of grade on these findings, the analyses were repeated, using only those with grade 2 tumors. A similar pattern was evidenced with significantly worse actuarial outcome at 4 years for the HORM group using the endpoints of a rising PSA (46%), any disease progression (24%), and a rising PSA or disease progression (47%).

CONCLUSION

Node-positive prostate cancer patients with regionally localized disease fared significantly better when combined local radiotherapy and early androgen ablation were used, as compared to early androgen ablation alone. Although the number of patients in the XRT/HORM group was small and follow-up was short, the combined treatment had a dramatic effect on disease outcome and, therefore, a larger prospective randomized trial is warranted.

Prostate cancer

Prostate cancer is the most common noncutaneous malignancy diagnosed in American men, and in 1994 it will pass lung cancer as the most common cancer diagnosed in the United States, with an estimated 200,000 new cases. The molecular biology of prostate carcinogenesis is rapidly advancing, and it is clear that, to a degree, prostate cancer is a heritable disease. The use of serum prostate-specific antigen (PSA) as a screening tool has been widely accepted by the medical community, although the evidence to support the efficacy of screening is not yet available. The curative approaches to organ-confined, clinically localized prostate cancer include radiation therapy, radical prostatectomy, and close observation in selected patients. The absence of well-designed clinical trials contributes to the confusion surrounding which curative treatment is the best option in individual patients. The standard approach to patients with evidence of extracapsular spread without distant metastases has been external-beam radiotherapy, although the results with radiation therapy alone in these patients has left considerable room for improvement. Innovative combined-modality approaches are currently being investigated at a number of institutions for these poor-prognosis patients. Three-dimensional conformal radiation therapy is currently being investigated at multiple institutions and offers some hope for improved results. The treatment of metastatic disease remains hormonal manipulation, although the exact nature of optimal androgen deprivation is currently a matter of considerable debate. In patients with hormone-refractory disease newer regimens using novel chemotherapy regimens offer some promise.

Neoadjuvant hormonal therapy and radical prostatectomy for clinical stage C carcinoma of the prostate

OBJECTIVE

To determine whether hormonal therapy prior to radical prostatectomy (neoadjuvant hormonal therapy) leads to improved results in patients with stage C prostate cancer.

PATIENTS AND METHODS

Thirty patients received neoadjuvant hormonal therapy for stage C carcinoma of the prostate. Eighteen patients who responded to treatment subsequently underwent extirpative surgery.

RESULTS

Fourteen of the 30 patients (47%) were diagnosed as being downstaged to clinical stage B disease following therapy. No major complications occurred. Pathology staging revealed only three patients (10%) to have organ-confined disease after radical prostatectomy.

CONCLUSIONS

Neoadjuvant hormonal therapy prior to radical prostatectomy offers little probability of rendering patients with clinical stage C carcinoma of the prostate free of disease. Further investigation of the efficacy of this treatment should be accomplished in randomized trials.

Improved local control and survival for surgically staged patients with locally advanced prostate cancer treated with up-front low dose rate iridium-192 prostate implantation and external beam irradiation

PURPOSE

In an effort to improve upon the historically poor local control and survival rates for locally advanced prostate carcinoma, a prospective multidisciplinary clinical trial was initiated using low dose rate Iridium-192 prostate implantation and external beam irradiation.

METHODS AND MATERIALS

Between January 1983 and September 1989, 57 patients with newly diagnosed bulky prostatic carcinoma (5 Stage B2, 52 Stage C) were treated at the Mayo Clinic (34 patients) and William Beaumont Hospital (23 patients) with (a) 5 Gy delivered preoperatively in one fraction, (b) pelvic lymphadenectomy with interstitial implantation of the prostate using Iridium-192 seeds via a perineal template to 30-35 Gy, and (c) 30.6 Gy external irradiation to prostate only in 17 fractions.

RESULTS

After lymphadenectomy, 30/57 (53%) patients had pathologically confirmed positive lymph nodes or "D1" disease. Thirty-four patients (60%) had Gleason scores > or = 7. Mean age at diagnosis was 63.3 years. Median overall follow-up was 72 months. The 5-year actuarial survival rate was 85% and disease-free survival was 63%. The 5-year survival for patients with negative nodes was 93% and with positive nodes was 79%. The corresponding survival for patients with Gleason scores < or = 6 was 96% and > or = 7 was 78%. Multivariate analysis demonstrated that of all covariates considered, only Gleason score had prognostic significance for disease-free survival (p < 0.05) and no covariates were statistically significant for overall survival. Thirty-nine of the 57 patients had a prostatic re-biopsy performed at 18 months. Pathologically confirmed local control was ultimately achieved in 31/39 (79.5%). There was no difference in survival in patients with positive re-biopsies vs. those with negative results. The 5-year actuarial rate of clinical local control was 94%. Three patients clinically failed locally and 21 demonstrated distant progression. The median time to progression was 34 months. Nineteen percent received some form of hormonal manipulation at the time of their treatment course and an additional 42% were treated with hormones during their follow-up period, primarily after distant failure. The grade 4 rectal ulceration rate decreased to 4.5% with modification of the brachytherapy technique. Three patients experienced grade 4 urinary incontinence and three patients experienced grades 3 or 4 chronic perineal pain.

CONCLUSION

These results indicate that bulky prostate carcinoma can be successfully controlled locally by this novel and aggressive approach with moderate toxicity and improved survival.

Localized carcinoma of the prostate (stages T1B, T1C, T2, and T3). Review of management with external beam radiation therapy

BACKGROUND

Optimal treatment for patients with localized carcinoma of the prostate is controversial. Radiation therapy is an established modality in the management of these patients, and several reports indicate the results are comparable to those achieved with radical prostatectomy. Recently effectiveness of therapy for carcinoma of the prostate is being evaluated in light of post-treatment prostate-specific antigen (PSA) determinations.

METHODS

A review was performed of multiple publications and data from selected institutions with large experience in the management of carcinoma of the prostate. Survival and clinical incidence of local recurrence and distant metastases were analyzed as well as preliminary data on postirradiation PSA levels. Factors that affect the outcome of therapy and relevant clinical trials are discussed.

RESULTS

Reported differences in the age of patients treated with radical prostatectomy (59-63 years), irradiation (63-69 years), or observation (69-75.5 years) were identified. The effect of surgical staging on outcome of irradiation was significant. In multiple series of patients clinically and radiographically staged, the 5-year disease-free survival (DFS) with external irradiation was 95-100% for clinical stage T1a, 80-90% for Stage T1b,c, and 50-70% for clinical Stage T3. A correlation has been identified between the initial PSA levels and the probability from freedom of chemical failure (PSA elevation) after definitive irradiation. In five series comprising 814 patients with Stage T1c and T2 tumors, the DFS (end point chemical failure) was 95%, with initial PSA of less than 4 ng/ml, 83-92% with 4.1-10 ng/ml, 35-85% with 10.1-20 ng/ml, and 10-63% with PSA higher than 20 ng/ml. In the various series, follow-up ranged from a median of 1.5 years to a minimum of 4 years. In two series of 225 and 201 patients receiving doses of 7500-8000 cGy, less morbidity has been observed with three-dimensional treatment planning conformal radiation therapy than with conventional irradiation. New directions for future clinical trials are discussed, including dose escalation studies; use of high linear energy transfer to improve locoregional tumor control; and combination of irradiation and androgen suppression to enhance local tumor control, decrease distant metastasis, and improve survival. Preliminary results of a randomized study recently reported by RTOG strongly suggest that the use of goserelin acetate and flutamide decreases the incidence of clinical local recurrence (12.4% in 225 patients) compared with a control group treated with irradiation alone (25.2% in 230 patients) and enhances disease-free survival.

CONCLUSIONS

Although modern approaches to the management of patients with localized carcinoma of the prostate with irradiation are effective, investigators must continue to critically assess policies of treatment, develop appropriately designed prospective clinical trials, and define the optimal management of patients with localized carcinoma of the prostate.

Radical prostatectomy for pathologic stage C prostate cancer: influence of pathologic variables and adjuvant treatment on disease outcome

A retrospective analysis was performed on 1,035 patients with pathologic Stage C prostate cancer treated with bilateral pelvic lymphadenectomy and radical retropubic prostatectomy. Of these patients, 661 received no immediate adjuvant treatment, 131 adjuvant radiotherapy only, and 103 postoperative adjuvant orchiectomy only. Overall crude survival at five, ten, and fifteen years was 91 percent, 68 percent, and 46 46 percent, respectively. Cause-specific survival was 96 percent, 81 percent, and 66 percent and overall nonprogression survival was 78 percent, 56 percent, and 48 percent at five, ten, and fifteen years, respectively. Patients with margin-positive and residual disease, high-grade tumors, large tumor bulk, and seminal vesicle involvement were more likely to receive adjuvant treatment. However, both univariately and multivariately, only tumor grade and increasing tumor volume correlated significantly with cause-specific survival and local and systemic progression. Adjuvant treatment significantly decreased local, systemic, and overall progression but did not improve cause-specific or crude survival. Orchiectomy and radiation appeared to demonstrate similar efficacy in controlling local recurrences: five-year local recurrence-free survival in this retrospective analysis was > 95 percent for both treatments compared with 84 percent for those without adjuvant treatment.

Prognostic factors in prostate cancer. Analysis of 874 patients treated with radiation therapy

BACKGROUND

The outcome of radiation therapy for localized prostate cancer depends on many pretreatment variables that are interrelated in complex ways. A multivariate analysis of 874 cases of prostate cancer treated between 1966 and 1988 was conducted. The median length of the follow-up period after radiation therapy was 6.7 years.

METHODS

The disease outcome and rate of survival was analyzed with the proportional hazards model for patients with stage A2 (104), stage B (168), or stage C (602) prostate cancer treated with radiation therapy as the only primary treatment.

RESULTS

Local recurrence rates were 12%, 24%, and 33% at 5, 10, and 15 years, respectively. In multivariate analysis, stage (A2 vs. B+C) and pathologic grade (1 + 2 vs 3 + 4) were independently related to local recurrence. At 10 years local control had been achieved in 79% of favorable cases (stage A2 or stage B/C, grade 1), but in only 62% of unfavorable cases (stage B/C, grade 4). Metastatic relapse rates were 25%, 38%, and 47% at 5, 10, and 15 years, respectively. Factors that independently correlated with metastasis were high pathologic grade, transurethral resection in stage C, elevated acid phosphatase levels, and being 60 years of age or younger. A favorable group of cases (stage A2/B, grade 1 or stage C, grade 1, no transurethral resection, older than 60 years of age) had a metastatic rate of only 10% after 10 years, whereas an unfavorable group (largely stage C, grades 3/4) had a metastatic rate approaching 70%. The overall survival rate was 77%, 49%, and 32% at 5, 10, and 15 years, respectively. Pathologic grade (1 vs 2 + 3 vs 4) and transurethral resection in stage C correlated with survival. A favorable group of patients (stage A2/B or stage C and grade 1) had a normal survival expectation of 15 years. An unfavorable group consisting of grade 4 tumors had a survival rate of less than 20% at 10 years.

CONCLUSIONS

The complexity and long natural history of prostate cancer demand careful stratification and follow-up examination to evaluate treatment results. The study of adjuvants to improve the local effectiveness of radiation and to mitigate the high metastatic rates in unfavorable local disease are urgent priorities.

Prostate-specific antigen. An important marker for prostate cancer treated by external beam radiation therapy

BACKGROUND

Prostate-specific antigen (PSA) is a valuable serum marker for prostate cancer. However, the prognostic importance of baseline PSA values in relation to other prognostic factors has not been elucidated. The incidence of postradiation rising PSA values has not been documented, and the extent to which PSA influences the assessment of radiation therapy is unclear. This study was designed to address these issues.

METHODS

Three hundred and fourteen consecutive patients with baseline PSA values who were treated between 1987 and 1991 with external beam radiation alone were reviewed for disease outcome and posttreatment PSA levels.

RESULTS

Clinical stages at diagnosis were: Stage A2, 87 (28%); Stage B, 108 (34%); and Stage C, 119 (38%). At a mean follow-up of 21 months, 25 patients had relapsed, 53 had developed rising PSA profiles, and 58 had either relapsed or had rising PSA profiles. The actuarial relapse rate was 20% at 4 years, the incidence of rising PSA profiles was 38% at 4 years, and the incidence of either relapse or rising PSA was 40% at 4 years. In multivariate analysis, baseline PSA value was the single most important factor predicting for local relapse, metastatic relapse, any disease relapse, and posttreatment rising PSA values. Using relapse or rising PSA as endpoints, the following four prognostic groupings based on baseline PSA and M.D. Anderson (MDA) grade were delineated: I, PSA less than or equal to 4 ng/ml, any grade; II, PSA greater than 4 but less than or equal to 10 ng/ml, Grades 1 and 2; III, PSA greater than 4 but less than or equal to 10 ng/ml, Grades 3 and 4 or PSA greater than 10 but less than or equal to 30 ng/ml, Grades 1 and 2; and IV, PSA greater than 10 but less than or equal to 30 ng/ml, Grades 3 and 4 or PSA greater than 30 ng/ml, any grade. The actuarial incidence of relapse or rising PSA in these groups was: I, less than 10% at 3 years; II, 20% at 3 years; III, 55% at 3 years; and IV, 90% at 30 months. When using traditional endpoints of disease outcome, the patients in this series had an outcome equivalent to that in 799 patients treated in our institution in the pre-PSA era; when using rising PSA profiles as endpoints, treatment was significantly less effective.

CONCLUSIONS

Pretreatment serum PSA level is the single most significant predictor of disease outcome after radiation therapy for local-regional prostate cancer. Moreover, postirradiation PSA values may potentially serve as an early endpoint to evaluate treatment efficacy. Using a rising posttreatment PSA profile as an index of treatment failure reveals that total and permanent eradication of prostate cancer with radiation therapy alone is not achieved as often as previously believed and that multimodal treatment approaches to prognostically unfavorable early stage disease need investigation.

Residual disease after radical surgery or radiation therapy for prostate cancer. Clinical significance and therapeutic implications

Radical treatment for prostate cancer aims at complete eradication of tumor. This review of published data makes clear that the goal is less frequently achieved than commonly presumed. Following radical prostatectomy extracapsular disease, carrying a significant risk of local recurrence, is found from 12-68% of the time depending on the clinical tumor stage. Local regrowth is associated with a poorer prognosis. A substantial proportion of patients whose prostate glands are rebiopsied more than 18 months after radiation therapy also have residual tumor. This again predicts for clinical relapse. The likelihood of a positive rebiopsy is dependent on original tumor size and current prostate specific antigen (PSA) levels. Strategies for managing residual disease are critically discussed.

Conservative approaches to the management of localized prostatic cancer

BACKGROUND

The management of early stage prostatic cancer is controversial.

METHODS

Pertinent literature concerning the conservative management of early stage prostatic cancer by early endocrine therapy (EET) or by deferred treatment (DT) was reviewed.

RESULTS

EET has not been systematically studied. Available evidence suggests that early stage prostatic cancer often progresses slowly and that DT results in a cancer-specific mortality of approximately 80% at 10 years.

CONCLUSIONS

EET warrants clinical investigation. DT is a management option, at least in patients with a life expectancy of 10 years or less.

Stage D1 prostate cancer. A nonrandomized comparison of conservative treatment options versus radical prostatectomy

BACKGROUND

Untreated Stage D1 prostate cancer is associated with a high progression rate. Various treatment modalities involving monotherapy alone have been associated with dismal results. In this retrospective study, the impact of combination therapy, local (surgery or radiation) and systemic (hormonal), compared with that of monotherapy on disease outcome was evaluated.

METHODS

The authors reviewed 631 patients who underwent pelvic lymphadenectomy for Stage D1 prostate cancer: 251 had radical prostatectomies and orchiectomies, 78 had radical prostatectomies alone, 97 received local irradiation and underwent orchiectomies, and 60 had orchiectomies alone.

RESULTS

Cause-specific survival rates for prostatectomy-orchiectomy-treated (PO) patients at 5 and 10 years were 91% and 78%, respectively; they were 84% and 54% for irradiation-orchiectomy-treated (IO) patients and 66% and 39% for orchiectomy alone-treated (O) patients, respectively. Controlling for the number of nodes, the difference between PO-treated and IO-treated patients was not significant; the former group had a significantly longer survival than the O-treated patients (P = 0.037). The 5-year and 10-year cause-specific survival rates for prostatectomy alone-treated patients were 91% and 75%, respectively, and 84% and 45% for irradiation alone-treated patients. Thus, cause-specific survival rates in prostatectomy alone-treated patients were significantly better (P = 0.0085).

CONCLUSIONS

For patients with Stage D1 prostate adenocarcinoma, radical prostatectomy and local irradiation as local treatments when combined with orchiectomy produce similar outcomes. These results should be verified in a prospective study.

Long-term evaluation of radical prostatectomy as treatment for clinical stage C (T3) prostate cancer

We reviewed the results of radical prostatectomy in 232 patients with clinical Stage C prostate cancer for comparison with published results of irradiation for clinical Stage C patients. Twenty-two percent were Stage B pathologically (i.e., overstaged clinically); 36 percent were pathologic Stage C and 42 percent were Stage D1. Fifty-four percent had had adjuvant treatment immediately postoperatively. Mean follow-up was 4.9 years, with 86 and 32 patients under observation at five and ten years, respectively. Overall, cause-specific, disease-free, and local recurrence-free survival rates were 84 percent, 89 percent, 69 percent, and 90 percent, respectively, at five years, and 72 percent, 82 percent, 56 percent, and 82 percent, respectively, at ten years. Although adjuvant hormonal treatment affected progression significantly (P = 0.0069), it did not affect survival significantly. When the analysis of survival to a female prostate-specific antigen (PSA) level was combined with clinical disease-free survival to provide a more accurate measure of disease progression, 90 percent, 51 percent, and 38 percent of patients with clinical Stage C prostate cancer were free of disease at one, five, and ten years, respectively. The clinical data suggest that radical surgery often combined with immediate adjuvant therapy may provide better disease control (including PSA values) than primary radiotherapy.

Frequency of residual neoplasm in the prostate following three-dimensional conformal radiotherapy

The incidence of residual neoplastic cells on prostatic biopsy following conventional external beam radiotherapy is reported to range from 40-90%. As a result, it has been stated that current modalities of radiotherapy may carry an unacceptable local failure rate even in patients irradiated for low stage disease. In order to assess the potential benefits of three-dimensional (3-D) treatment planning, an unselected, consecutive group of patients with localized adenocarcinoma of the prostate was evaluated. This study was designed to determine the frequency of residual cancer in the prostate two years following definitive external beam radiotherapy designed, using a 3-D planning system. Between February 1988 and February 1989, 30 consecutive patients with localized (Stage T1-T3NxMo) adenocarcinoma of the prostate received definitive external beam radiotherapy. All treatment fields were designed with a computed tomography (CT)-based 3-D treatment planning system, resulting in a static conformal radiotherapy plan. The minimum dose delivered to the target volume, which included the prostate, periprostatic tissues, and a 1 cm margin, was between 65 and 69 cGy. Twenty-six patients had Stage T1, T2NxMo primary tumors and four were T3NxMo. Two years following the completion of treatment, all patients underwent digital rectal examination, transrectal ultrasound examination of the prostate with multiple biopsies, bone scan, and serum prostate specific antigen (PSA) determinations. Residual prostate cancer was proven by biopsy in six of 30 patients (20%). Four of 26 (15%) with Stage T1 and T2 tumors had a positive biopsy. However, two of the four Stage T3 tumors had postradiation biopsies positive for cancer (50%). Only one patient with a positive biopsy had an abnormal rectal examination. Five of the eight patients with elevated serum PSA levels after two years had residual neoplasia identified on biopsy. One of six patients with an abnormal postradiation ultrasound had residual tumor. Only one of the 22 patients (5%) with a normal serum PSA at two years had a positive postradiation biopsy. In patients with localized prostate cancer, the use of 3-D static conformal radiotherapy followed by multiple ultrasound guided biopsies confirmed the efficacy of external beam radiotherapy in low stage disease. We believe that the low incidence of positive biopsies in this study resulted from the benefits of 3-D treatment planning as well as the fact that all patients were evaluated, whereas past studies have been in selected patient groups when suspicion of residual disease existed prior to biopsy.(ABSTRACT TRUNCATED AT 400 WORDS)

Prostate cancer treated by radiotherapy: a multivariate study

According to respective proportions of evolutive status groups, results of multivariate studies are difficult to interpret. Among the 1099 cases of local form of prostate cancer, treated by radiotherapy from 1975 to 1982 in 16 French Anticancer Institutes, we can observe two homogeneous status groups of patients: disease-free survivors (285 cases) and patients who died of prostate cancer (278 cases). These correspond to 51% of the whole population. Among other things, they are comparable in size, for age at the beginning of radiotherapy and for delay between histologic diagnostic and radiotherapy. We chose to analyse them using multivariate analysis. To take survival into account, we used a Cox model and Kaplan-Meier curves; the group deceased of prostate cancer was further analyzed by a tree-structured regression method. The Cox model and the Kaplan-Meier curves confirmed two main explicative factors: Stage (p < 0.0001) and tumor grade (p < 0.001). Poorer evolution occurs in extracapsular forms and grade I has better survival than others. The tree-structured regression method indicates two other pejorative factors: hormonotherapy prior to radiotherapy and the presence of cardiovascular pathology. Though the pelvic dose does not appear to be a main explicative factor, it seems to improve survival and delay between radiotherapy and recurrence or metastasis in some categories of cases. Other factors such as tumor dose, age and delay between diagnosis and radiotherapy were not found to be significant. These results cannot be extended to the whole population for which they do not constitute a predictive study. We consider them as "baseline data".(ABSTRACT TRUNCATED AT 250 WORDS)