Prognostic Significance of Pretreatment Immune Cell Infiltration in Muscle Invasive Bladder Cancer Treated with Definitive Chemoradiation: Analysis of NRG RTOG 0524 and 0712

PURPOSE/OBJECTIVE(S)

Chemoradiation therapy (CRT) is an organ conserving approach in the treatment of locally advanced bladder cancer. Chemoradiation is thought to potentially result in immunogenic stimulation, and bladder cancer is often a tumor with high immune cell infiltration. Thus, we aimed to profile the tumor immune microenvironment of bladder cancer and identify prognostic immune biomarkers for CRT response by profiling tumor samples from NRG/RTOG 0524 and 0712, two prospective trials of CRT in muscle invasive bladder cancer (MIBC).

MATERIALS/METHODS

Pretreatment tissue samples from both trials were profiled using Cofactor Genomics ImmunoPrism, an RNA sequencing assay that uses gene expression profiles to quantify immune cell populations in the tumor microenvironment (TME). Differential gene expression was estimated for different immune cell type proportions across samples. Kaplan-Meier survival analysis and log rank tests were performed to evaluate differences in overall survival (OS) stratified by genes influenced by immune cell proportions or genes associated with immune response signatures.

RESULTS

A total of 70 samples (43 from RTOG 0524 and 27 from RTOG 0712) underwent analysis using the ImmunoPrism assay. Immune cell proportions were as follows: CD8 T cells: median 1.2%, CD4 T cells: median 0.8%, Treg cells: median 9.2%, CD19 B cells: median 5.1%, M2 macrophages: median 0.8%, M1 macrophages: median 0%. Unbiased clustering based on gene expression profiles driven by immune cell proportions demonstrated two groups: cluster 1 with a low percentage of immune cells and shorter OS (median 31 months) and cluster 2 with a high percentage of immune cells and longer OS (median 101 months, p = 0.036). Higher expression of genes associated with T cell infiltration (CD8A and ICOS) was associated with improved OS (104 vs 35 months, p = 0.028, HR = 0.48 (0.25 - 0.94), p = 0.031) as was higher expression of IDO1, which is associated with the interferon gamma pathway (104 vs 35 months, p = 0.042, HR = 0.49 (0.24 - 0.99), p = 0.046).

CONCLUSION

Bladder tumors have a wide range of immune cell infiltration in the TME. Increased immune cell proportions are prognostic for OS following CRT, as well as a higher expression of genes associated with T cell infiltration interferon gamma signaling. These findings have implications for the integration of immunotherapy in the definitive management of MIBC; and can be explored further in the ongoing NRG/SWOG 1806 trial.

Potential location of a bladder tumor suppressor gene on chromosome 9q at 9q13 to 9q22.1

Allelic losses involving chromosome 9q occur in a significant percentage of bladder tumors. Experimental evidence suggests that a putative tumor suppressor gene located on this chromosome may play a role in the development of bladder cancer. The precise location of this potential tumor suppressor gene is not clear. Previous studies have targeted a large region between 9p12-13 and 9q22 or 9p12 and 9q34.1 as the likely site. To further delineate the location of this gene, we examined 49 tumors by loss of heterozygosity (LOH) analysis, using seven microsatellite polymorhpic loci spanning from 9p21 to 9q34 of the chromosome. LOH was found in at least one of the loci in 20 (41%) of the tumors examined, and the majority (12 of 17; 71%) of the losses on 9q involved large segments or the entire chromosome arm. Although many of the tumors with large losses on 9q also involved 9p21, several tumors with small losses did not involve the 9p marker. Conversely, there were tumors with 9p21 losses that did not involve the q-arm. These data agree with recent findings that distinct tumor suppressor genes associated with bladder cancer are located on separate arms of chromosome 9. Among tumors with single locus LOHs, the most common deletion was located in 9q 13-21.2, which was detected by probe D9S15. This also is the smallest area of critical loss when LOH patterns of tumors with partial or interstitial losses were examined. Results of the study therefore suggest that a potential tumor suppressor gene may reside within or near the region of 9q13-22.1.

Initial report of RTOG 9601, a phase III trial in prostate cancer: Effect of anti-androgen therapy (AAT) with bicalutamide during and after radiation therapy (RT) on freedom from progression and incidence of metastatic disease in patients following radical prostatectomy (RP) with pT2-3,N0 disease and elevated PSA levels

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Background: To test if long term AAT when combined with RT in these patients (pts) with prostate cancer (PC) will improve cancer control outcomes as well as overall survival (OS).

Methods: Post-RP pts with pT3,N0 or with pT2,N0 (and positive margins) who have an elevated PSA were entered on a phase III, double-blinded, placebo-controlled trial of RT alone (64.8 Gy in 1.8 Gy fractions) vs RT + AAT (24 months of bicalutamide, 150mg daily) during and after RT. The primary end point is OS.

Results: From 3/98 to 3/03, 771 eligible pts (median age 65) were randomized to RT + AAT (387) or RT alone (383). Pretreatment characteristics were balanced. 672 (87%) had a PSA nadir after RP of < 0.5 ng/mL. 655 (85%) had an entry PSA value of <1.6, 115 (15%) had an entry PSA of 1.6-3.9. Median follow-up was 7.1 years. Actuarial OS at 7 years was 91% for RT + AAT and 86% for RT alone. Too few primary end-point events have occurred to allow a statistical comparison between groups. Freedom from PSA progression (FFP) at 7 years was 57% for RT + AAT and 40% for RT alone (P < 0.0001); for 226 pts with GS < 7 were 63% and 50% (P<0.02), for 411 GS 7 these were 55% and 39% (P<0.0006), and for 134 GS 8-10 were 56% and 26% (P < 0.0008). The 7-yr cumulative incidence of metastatic PC was less in the RT and AAT arm, 7% vs 13% in the RT arm (p<0.041). Late grade 3-4 toxicities were similar in both arms. By category the combined grade 3-4 toxicities for RT + AAT and RT alone were: bladder 6% vs 5% bowel 2% vs 1%, cardiac 3% vs 2%. Gynecomastia (mostly grades 1-2) differed significantly, 89% vs15%. In the RT + AAT arm grade 3 was the highest liver toxicity, which occurred in 3 pts.

Conclusions: The addition of 24 months of bicalutamide 150 mg daily during and after RT significantly improved FFP and reduced the incidence of metastatic PC without adding significantly to RT toxicity. The significance of benefit in OS, as well analysis of risk-stratified subsets, wait longer follow-up.

No significant financial relationships to disclose.

Long-term QOL outcome after proton beam monotherapy for localized prostate cancer

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Background: High-dose conformal proton radiation for localized prostate cancer results in favorable clinical outcomes and low toxicity rates. Here, we report long-term quality of life (QOL) outcome for men treated with conformal protons.

Methods: Serial QOL questionnaires were administered to men who received proton radiation. Long-term questionnaires (minimum 2 years) were completed by 72 patients. Men were stratified into functional groups from their baseline questionnaires (normal, intermediate or poor function) for each symptom domain. Symptom scores were calculated at baseline and long-term follow-up and expressed as mean values. QOL changes were assessed overall and within functional groups in a paired fashion using the Student's t-test.

Results: The median age at treatment and follow-up were 66 years and 44 months, respectively. The median dose was 82 GyE (range 74-82 GyE). For all 72 patients, there were increased scores for incontinence (ID) (3.2 baseline vs. 9.9 long-term, p=<0.001), obstructive/irritative voiding (OID; 20 vs. 24, p=0.028), bowel (BD; 4.4 vs. 8.0, p=0.001) and sexual dysfunction (SD; 25 vs. 48, p<0.001). When stratified by functional category, more specific estimates were possible. For ID, only normal function was associated with a significant increased score (0 vs. 8.4 at baseline and long-term, p=<0.001); for OID, only the group with normal baseline function showed a significant increased score (12 vs. 17, p=0.01); similarly for BD, only men with normal function had a significant increased score (0 vs. 5.4, p<0.001). For SD, the score increased in men with normal (1.4 vs. 30, p<0.001) and intermediate function (17 vs. 46, p<0.001).

Conclusions: Patient reported outcomes are sensitive indicators of treatment related sequelae and here quantitate, for the first time, the long-term consequences of proton monotherapy for prostate cancer. Analysis by baseline functional category is a useful means of predicting long-term QOL scores for an individual patient. High-dose proton radiation was associated with small increases in bowel dysfunction, obstructive/irritative voiding dysfunction and incontinence. With long term follow-up, sexual dysfunction increased more than any other symptom domain.

No significant financial relationships to disclose.

Adjuvant radiation therapy for early-stage seminoma: Proton-photon comparison and second cancer risk

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Background: Seminoma constitutes the majority of testicular cancers and 75% percent of patients present with localized disease. Given that seminoma remains the most curable solid tumor, concerns of toxicity including late sequelae such as excess malignancies have given pause to the use of conventional adjuvant radiation therapy (RT) following orchiectomy for early-stage seminoma. As a result of the unique physical dose deposition characteristics of protons to avoid normal tissue, we evaluated both photon and proton beam therapy (PBT) treatment plans for para-aortic irradiation to assess dose distributions to organs at-risk and model rates of second cancers.

Methods: Ten patients with stage I seminoma treated with conventional adjuvant para-aortic AP-PA photon RT to 25.5 Gy between 2004-2009 at Massachusetts General Hospital had PBT plans generated (AP-PA and PA alone). The dose differences to critical organs, as modeled by Equivalent Uniform Dose (EUD), were examined. The risks of second primary malignancies were calculated using validated methods and compared both to each other and to baseline population risks.

Results: PBT plans were superior to photons in limiting dose to organs at-risk. The volume of whole body normal tissue spared 0.1 Gy was 9.0L and 7.8L for PA and AP-PA protons, respectively, compared to photons. The volume spared 1Gy was 5.0L and 3.8L for PA and AP-PA protons, respectively; while the volume spared 10Gy was 1.3L and 0.85L, respectively. PBT decreased the EUD by 46% (8.2 Gy) and 64% (10.2 Gy) to the stomach and large bowel, respectively (p<0.01), presumably translating into lower levels of nausea and fatigue. Notably, PBT was found to avert 612 excess second cancers among a population of 10,000 men diagnosed at age 35 and surviving to age 75 (p<0.01).

Conclusions: In this comparative dosimetric and modeling study, the use of protons provided a favorable dose distribution with an ability to limit unnecessary exposure to critical normal structures in the treatment of stage I seminoma patients. It is expected that this will translate into decreased acute toxicity and reduced risk of second cancers, for which prospective studies are warranted.

No significant financial relationships to disclose.

Body mass index and mortality in men treated for locally advanced prostate cancer: An analysis of RTOG 85–31

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Background: Greater body mass index (BMI) is associated with shorter time to prostate-specific antigen (PSA) failure following radical prostatectomy. We investigated whether BMI is associated with prostate cancer-specific mortality (PCSM) in a large randomized trial of men treated with radiation therapy (RT) and androgen deprivation therapy (ADT) for locally advanced prostate cancer. Methods: Between 1987 and 1992, 945 eligible men with locally advanced prostate cancer were enrolled on a phase III trial (RTOG 85- 31) and randomized to RT and immediate goserelin (Arm I) or RT alone followed by goserelin at relapse (Arm II). Height and weight data were available at baseline for 788 (83%) subjects. Cox regression analyses were performed to evaluate the relationships between BMI and all-cause mortality, PCSM, and non-prostate cancer mortality. Covariates included age, race, treatment arm, history of prostatectomy, nodal involvement, Gleason score, clinical stage, and BMI. Results: The 5-year PCSM rate for men with BMI<25kg/m2 was 6.5%, compared to 13.1% and 12.2% in men with BMI=25-<30 and BMI=30, respectively (Gray’s p=0.005). In multivariable analyses, as shown in the Table , greater BMI was significantly associated with higher PCSM [for BMI=25-<30, hazard ratio (HR) 1.52, 95% confidence interval (CI) 1.02–2.27, p=0.04; for BMI=30, HR 1.65, 95% CI 1.02–2.66, p=0.04]. BMI was not associated with non-prostate cancer or all-cause mortality. Conclusions: Greater baseline BMI is independently associated with higher PCSM in men with locally advanced prostate cancer. Further studies are warranted to evaluate the mechanism(s) for increased mortality and to assess whether weight loss after prostate cancer diagnosis alters disease course.

[Table: see text]

No significant financial relationships to disclose.

Does timing of androgen deprivation influence radiation-induced toxicity? A secondary analysis of Radiation Therapy Oncology Group protocol 9413

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Background: We conducted a secondary analysis of RTOG 9413 to compare if the timing of antiandrogen-therapy, concomitant versus adjuvant, influences the incidence of rectal toxicity in whole pelvic radiotherapy. Methods: For the purpose of this secondary analysis, we analyzed the 2 of the 4 arms of the study, in which all patients received radiotherapy to the whole pelvis followed by a boost to the prostate and excluded the two arms that received prostate only radiotherapy. The 2 arms differed only in the timing of the total of 4 months of total androgen deprivation (TAD): arm I (320 patients), TAD was begun 2 months before the start of radiotherapy and continued during radiotherapy. Arm III (319 patients), TAD started immediately after the completion of radiotherapy. Both acute rectal and acute urinary toxicities (CTC v.2.0), testosterone (measured at baseline and yearly after) and other patients data were modeled using the multivariate logistic regression and the multivariate Cox-proportional hazards regression. Results: Median follow up for all patients is 6.0 and 5.8 years (arm I and II, resp.). 43 (13%) patients in each arm had abnormally low testosterone before start of TAD. Late grade 2 - 5 rectal toxicity occurred in 16% and 13% and urinary toxicity in 18% and 20% (arm I and II, resp.). Frequency (or occurrence) of late rectal toxicity (grade 0–1 vs. 2–5, p = 0.2170) and late urinary toxicity (grade 0–1 vs. 2–5, p = 0.4204) are not significantly different between the two arms. The only risk factors for late rectal toxicity in a multivariate regression model was acute rectal toxicity (OR 1.48, p = 0.025), but not abnormal testosterone level at baseline (p = 0.718) or treatment arm (p = 0.874). For late urinary toxicity: age (OR = 1.588, p = 0.010), RT field size (OR 1.004, p < 0.025), baseline testosterone (OR 1.718, p = 0.028), and acute (grade 2–4) toxicity (OR = 1.664, p = 0.006) but not treatment arm (p = 0.928) were risk factors. Conclusions: While late toxicity was not different for concomitant vs. adjuvant hormonal therapy, an abnormally low testosterone level at baseline is a risk factor for late urinary toxicity and not late rectal toxicity.

No significant financial relationships to disclose.

Ki-67 staining is a strong predictor of distant metastasis and mortality for men with prostate cancer treated with radiotherapy plus androgen deprivation: Radiation Therapy Oncology Group Trial 92-02

PURPOSE

The Ki-67 staining index (Ki67-SI) has been associated with prostate cancer patient outcome; however, few studies have involved radiotherapy (RT) -treated patients. The association of Ki67-SI to local failure (LF), biochemical failure (BF), distant metastasis (DM), cause-specific death (CSD) and overall death (OD) was determined in men randomly assigned to short term androgen deprivation (STAD) + RT or long-term androgen deprivation (LTAD) + RT.

PATIENTS AND METHODS

There were 537 patients (35.5%) on Radiation Therapy Oncology Group (RTOG) 92-02 who had sufficient tissue for Ki67-SI analysis. Median follow-up was 96.3 months. Ki67-SI cut points of 3.5% and 7.1% were previously found to be related to patient outcome and were examined here in a Cox proportional hazards multivariate analysis (MVA). Ki67-SI was also tested as a continuous variable. Covariates were dichotomized in accordance with stratification and randomization criteria.

RESULTS

Median Ki67-SI was 6.5% (range, 0% to 58.2%). There was no difference in the distribution of patients in the Ki-67 analysis cohort (n = 537) and the other patients in RTOG 92-02 (n = 977) by any of the covariates or end points tested. In MVAs, Ki67-SI (continuous) was associated with LF (P =.08), BF (P =.0445), DM (P <.0001), CSD (P <.0001), and OD (P =.0094). When categoric variables were used in MVAs, the 3.5% Ki67-SI cut point was not significant. The 7.1% cut point was related to BF (P =.09), DM (P =.0008), and CSD (P =.017). Ki67-SI was the most significant correlate of DM and CSD. A detailed analysis of the hazard rates for DM in all possible covariate combinations revealed subgroups of patients treated with STAD + RT that did not require LTAD.

CONCLUSION

Ki67-SI was the most significant determinant of DM and CSD and was also associated with OD. The Ki67-SI should be considered for the stratification of patients in future trials.

Selective bladder preservation for muscle-invasive transitional cell carcinoma of the urinary bladder

Invasive transitional cell carcinoma (TCC) of the urinary bladder is traditionally treated with radical cystectomy. This approach results in great morbidity and lifestyle changes, and approximately half of the patients treated in this way will experience recurrent TCC despite surgery. An alternative approach using selective bladder-preservation techniques incorporates transurethral resection of bladder tumours, radiation therapy, and chemotherapy. Over the past 20 years, international experience has demonstrated that this approach is feasible, safe, and well tolerated. Furthermore, the long-term outcomes of overall survival and disease-free survival compare favourably with the outcomes from radical cystectomy. The most important predictor of response is stage, with significantly higher long-term survival in patients with T2 disease. Another important positive predictor of complete response to therapy is the ability of the urologic oncologist to remove all visible tumour through a transurethral approach prior to initiation of radiation therapy. A negative predictive factor is the presence of hydronephrosis, and age and gender do not affect disease-free survival. The majority of patients who enjoy long-term survival do so with an intact native bladder. Quality of life studies have demonstrated that the retained bladder functions well in nearly all of these patients. Selective bladder preservation will not entirely take the place of radical cystectomy, but should be offered as an important alternative to patients newly diagnosed with muscle-invasive TCC.

10-Year Outcome for Men With Localized Prostate Cancer Treated With External Radiation Therapy:: Results of a Cohort Study

PURPOSE

We determine the efficacy of conventional dose, external beam radiation for localized prostate cancer using cohort analysis with maximized followup.

MATERIALS AND METHODS

A total of 205 men with T1-2 prostate cancer were treated with conventional external beam radiation to a median and modal dose of 68.4 Gy during a 16-month period from 1991 to 1993. Followup was maximized in these patients, and median followup for those alive with or without disease was 114 months.

RESULTS

Median patient age at treatment was 72 years, and overall survival at 5 and 10 years was 78% and 53%, respectively. The actuarial risk of local failure was 18% at 10 years as was the risk of metastatic disease. The actuarial risk of being free of biochemical failure at 10 years (American Society for Therapeutic Radiology and Oncology definition) was 49%. That risk was 42% if the definition was used without backdating failure to a time between last low value and first increase. When a crude analysis of 10-year outcome was performed 127 of the 205 treated patients (62%) were still alive, including 59% with no evidence of biochemical failure and a median prostate specific antigen of 1.0 ng/ml. Of the 78 men (38% of total) who died during the 10 years 32 died either of or with recurrent cancer.

CONCLUSIONS

Mature followup minimizes many of the biases seen in previously published radiation series. This study provides a yardstick against which newer radiation modalities may be measured.

Prostate cancer DNA ploidy and response to salvage hormone therapy after radiotherapy with or without short-term total androgen blockade: an analysis of RTOG 8610

PURPOSE

DNA ploidy has consistently been found to be a correlate of prostate cancer patient outcome. However, a minority of studies have used pretreatment diagnostic material and have involved radiotherapy (RT)-treated patients. In this retrospective study, the predictive value of DNA ploidy was evaluated in patients entered into Radiation Therapy Oncology Group protocol 8610. The protocol treatment randomization was RT alone versus RT plus short-course (approximately 4 months) neoadjuvant and concurrent total androgen blockade (RT+TAB).

PATIENTS AND METHODS

The study population consisted of 149 patients, of whom 74 received RT alone and 75 received RT+TAB. DNA content was determined by image analysis of Feulgen stained tissue sections; 94 patients were diploid and 55 patients were nondiploid. Kaplan-Meier univariate survival, the cumulative incidence method, and Cox proportional hazards multivariate analyses were used to evaluate the relationship of DNA ploidy to distant metastasis and overall survival.

RESULTS

DNA nondiploidy was not associated with any of the other prognostic factors in univariate analyses. In Kaplan-Meier analyses, 5-year overall survival was 70% for those with diploid tumors and 42% for nondiploid tumors. Cox proportional hazards regression revealed that nondiploidy was independently associated with reduced overall survival. No correlation was observed between DNA ploidy and distant metastasis. The diminished survival in the absence of an increase in distant metastasis was related to a reduction in the effect of salvage androgen ablation; patients treated initially with RT+TAB and who had nondiploid tumors had reduced survival after salvage androgen ablation.

CONCLUSIONS

Nondiploidy was associated with shorter survival, which seemed to be related to reduced response to salvage hormone therapy for those previously exposed to short-term TAB.

Selective bladder preservation by combined modality protocol treatment: long-term outcomes of 190 patients with invasive bladder cancer

OBJECTIVES

To evaluate the outcomes of patients with muscle-invasive Stage T2-4a bladder carcinoma managed by transurethral surgery and concurrent chemoradiation.

METHODS

A total of 190 patients were treated on institutional prospective protocols using concurrent cisplatin-containing chemotherapy and radiotherapy after rigorous transurethral resection of the bladder tumor. Patients were re-evaluated by repeated biopsy and urine cytologic analysis after 40 Gy, with the initial tumor response guiding subsequent therapy. One hundred twenty-one patients with a complete response by cytologic and histologic examination and those medically unfit for cystectomy received boost chemoradiation to 64 to 65 Gy. Those patients without a complete response were advised to undergo radical cystectomy. A total of 66 patients (35%) ultimately underwent radical cystectomy; 41 for less than a complete response and an additional 25 for recurrent invasive tumors. The median follow-up was 6.7 years for all surviving patients.

RESULTS

The 5 and 10-year actuarial overall survival rate was 54% and 36%, respectively (Stage T2, 62% and 41%; Stage T3-T4a, 47% and 31%, respectively). The 5 and 10-year disease-specific survival rate was 63% and 59% (Stage T2, 74% and 66%; Stage T3-T4a, 53% and 52%), respectively. The 5 and 10-year disease-specific survival rate for patients with an intact bladder was 46% and 45% (Stage T2, 57% and 50%; Stage T3-T4a, 35% and 34%), respectively. The pelvic failure rate was 8.4%. No patient required cystectomy because of bladder morbidity.

CONCLUSIONS

The 10-year overall survival and disease-specific survival rates are comparable with the results reported for contemporary radical cystectomy for patients of similar clinical and pathologic stage. One third of patients treated on protocol with the goal of bladder sparing ultimately required a cystectomy. A trimodality approach with bladder preservation based on the initial tumor response is, therefore, safe, with most long-term survivors retaining functional bladders.

Late normal tissue sequelae in the second decade after high dose radiation therapy with combined photons and conformal protons for locally advanced prostate cancer

PURPOSE

We determined the long-term normal tissue effects of 77.4 Gy. delivered to the prostate in patients with locally advanced prostate cancer.

METHODS AND MATERIALS

Between 1976 and 1992, 167 men with stages T3 to 4 prostate cancer were treated on protocol with 50.4 Gy. photons at 1.8 Gy. per fraction using a 4-field box arrangement, followed by a conformal perineal proton boost of 27 Gy. (cobalt Gy. equivalent) in 11 fractions. The chart was reviewed and 39 of the 42 surviving patients were interviewed. Median followup was 13.1 years (range 7 to 23). Normal tissue morbidity was recorded using Radiation Therapy Oncology Group criteria and the late effects normal tissue scale.

RESULTS

The actuarial incidence of grade 2 or greater genitourinary morbidity was 59% at 15 years. However, these grade 2 or greater problems persisted to the time of the interview in only 7 of 39 cases. The actuarial incidence of grade 2 or greater hematuria was 21% at 5 years and 47% at 15. For grade 3 or greater hematuria the risk was 3% and 8% at 5 and 15 years, respectively. No patient required cystectomy but 1 required diversion for morbidity. Urethral stricture and urinary incontinence with pads needed developed in 4 and 3 men, respectively. This particular morbidity was strongly associated with previous or subsequent prostate surgery. The actuarial incidence of grade 2 or greater gastrointestinal morbidity was 13% at 5 and 15 years, while grade 1 rectal bleeding occurred in another 41%.

CONCLUSIONS

High dose conformal radiation to the prostate is followed by a high rate of low grade rectal bleeding but a low rate of grade 2 or higher gastrointestinal morbidity. This rate is stable and does not increase beyond 5 years. Genitourinary morbidity continues to develop well into the second decade after treatment, although high grade morbidity is uncommon. These findings do not suggest that the modern trend toward high dose prostate treatment with conformal techniques will result in a high incidence of serious and permanent late sequelae but it appears that hematuria will be common.

Selective bladder conservation using transurethral resection, chemotherapy, and radiation: management and consequences of Ta, T1, and Tis recurrence within the retained bladder

OBJECTIVES

Although radical cystectomy remains the standard of care for invasive bladder cancer in the United States, many groups are exploring the use of trimodality therapy using transurethral resection of the bladder tumor, radiation, and chemotherapy in an attempt to spare patients the need for cystectomy. As transitional cell carcinoma often arises from a urothelial field change, there is concern that the retained bladder is at risk of subsequent superficial (Ta, T1, Tis) tumors, some of which may have lethal potential. This study reports the outcomes of those patients with superficial relapse of transitional cell carcinoma after trimodality therapy.

METHODS

One hundred ninety patients were treated using a series of trimodality therapy protocols between 1986 and 1998. All patients received induction chemotherapy and radiation and were selected for bladder preservation on the basis of a cytologic and histologic complete response. One hundred twenty-one patients had a complete response and formed the subjects of this study.

RESULTS

With a median follow-up of 6.7 years for patients still alive, 32 experienced a superficial relapse (26%). The median time to this failure was 2.1 years. Sixty percent of the superficial failures were carcinoma in situ (Tis) and 67% arose at the site of the original invasive tumor. The risk of superficial failure was higher among those who had Tis associated with their original muscle-invasive tumor. Twenty-seven of these 32 cases were managed conservatively with transurethral resection and intravesical therapy. The irradiated bladder tolerated this therapy well and only 3 patients required treatment breaks. The 5 and 8-year survival was comparable for those who experienced superficial failure (68% and 54%, respectively) and those who had no failure at all (n = 74, 69% and 61%, respectively). However, a substantially lower chance of being alive with the native bladder owing to the need for late salvage cystectomies (61% versus 34%) was found. Cystectomy became necessary in 31% (10 of 32) either because of additional superficial recurrence (n = 7) or progression to invasive disease (n = 3).

CONCLUSIONS

A trimodality approach to transitional cell bladder cancer mandates lifelong cystoscopic surveillance. Although most completely responding patients retain their bladders free from invasive relapse, one quarter will develop superficial disease. This may be managed in the standard fashion with transurethral resection of the bladder tumor and intravesical therapies but carries an additional risk that late cystectomy will be required.

AN ORGAN-PRESERVING APPROACH TO MUSCLE-INVADING TRANSITIONAL CELL CANCER OF THE BLADDER

Bladder-preserving treatment for muscle-invasive disease is based on the response of the tumor to induction combined modality therapy. In the future, an organ-conserving approach will be widely offered as a safe and reasonable alternative to radical cystectomy.

The initial results in muscle-invading bladder cancer of RTOG 95-06: phase I/II trial of transurethral surgery plus radiation therapy with concurrent cisplatin and 5-fluorouracil followed by selective bladder preservation or cystectomy depending on the initial response

PURPOSE

To assess the safety, tolerance, and efficacy of transurethral surgery plus concomitant cisplatin, 5-fluorouracil (5-FU), and radiation therapy in conjunction with selective bladder preservation in patients with muscle-invading bladder cancer. Patients and Methods. Thirty-four eligible patients with clinical stage T2-T4a, Nx M0 bladder cancer without hydronephrosis were entered into a protocol aimed at selective bladder preservation. Treatment began with as complete a transurethral resection as possible followed by induction chemoradiation. This consisted of cisplatin 15 mg/m(2) i.v. and 5-fluorouracil (5-FU) 400 mg/m(2) i.v. in the mornings on d 1, 2, 3, 15, 16, and 17. On d 1, 3, 15, and 17, radiation was given immediately following the chemotherapy using twice-a-day 3 Gy per fraction cores to the pelvis for a total radiation dose of 24 Gy. Response was evaluated by cystoscopy, cytology, and rebiopsy four weeks later. Patients with a complete response received consolidation therapy with the same drugs and doses on d 1, 2, 3, 15, 16, and 17 combined with twice-daily radiation therapy to the bladder and bladder tumor volume of 2.5 Gy per fraction for a total consolidation dose of 20 Gy and a total induction plus consolidation dose to the bladder and bladder tumor of 44 Gy. Patients who did not achieve a complete response were advised to undergo prompt cystectomy, as were those with a subsequent invasive recurrence. The median follow up is 29 months.

RESULTS

Of the 34 eligible patients, 26 had a visibly complete transurethral resection. One patient did not complete induction treatment due to acute hematologic toxicity. After induction treatment, 22 (67%) of the 33 patients had no tumor detectable on urine cytology or rebiopsy. Of the 11 patients who still had detectable tumor, six underwent radical cystectomy and five underwent consolidation chemoradiation (one because of refusal to have the recommended cystectomy and four because the treating institutions erroneously assigned them to receive consolidation chemoradiation rather than cystectomy). No patient has required a cystectomy for radiation toxicity. Six patients have died of bladder cancer. The actuarial overall survival at three years is 83%. The probability of surviving with an intact bladder is 66% at three years. A total of seven patients (21%) developed grade 3 or grade 4 hematologic toxicity in conjunction with this treatment.

CONCLUSION

This aggressive protocol comprising local surgery plus concurrent 5-FU, cisplatin, and high-dose hypofractionated radiation has been associated with moderately severe hematologic toxicity. Longer follow-up will be necessary to assess efficacy. Both the 67% complete response rate to induction therapy and the 66% three-year survival with an intact bladder are encouraging.

Bladder preservation in muscle-invasive bladder cancer by conservative surgery and radiochemotherapy

Organ preservation has been investigated in muscle-invasive bladder cancer over the past decades as an alternative to standard radical cystectomy. The results of large prospective protocols and population-based studies suggest that an organ-preserving approach is possible without deferring the survival probability. Organ preservation requires a trimodal schedule, including transurethral surgery (transurethral resection of bladder tumor (TURBT)), radiation, and chemotherapy. A complete TURBT is the most important single prognostic factor, and should be attempted. Radiotherapy, in conjunction with concurrent platinum-based chemotherapy, can control the vast majority of urothelial bladder tumors. The histologically-proven complete remission rates of macroscopic tumors (unresectable by TURBT) lie in the range of about 70%. After radiochemotherapy, a histological response evaluation with repeated TURBT is recommended. Patients with residual tumor require salvage cystectomy. In cases of complete remission, patients can maintain their bladders but they should be closely followed over years. The risk of severe late-radiation sequelae is low, in the range of less than 5%. About 75% of long-term survivors maintain a normally functioning bladder.

Thymosin beta-15 predicts for distant failure in patients with clinically localized prostate cancer-results from a pilot study

OBJECTIVES

To report the results of a pilot study on the prognostic value of a newly identified actin-binding protein, thymosin beta-15 (Tbeta15), in predicting prostate-specific antigen (PSA) and bone failure in patients with Gleason 6/10 clinically localized prostate cancer.

METHODS

Thirty-two patients (median age 70 years) with clinically localized, moderately differentiated (Gleason 6/10) prostate cancer treated by external beam radiotherapy alone (68.4 Gy) with available paraffin blocks at the Massachusetts General Hospital were evaluated for this pilot study. All patients had clinical Stage M0 disease at initial presentation, which was documented by bone scan (T1c-4,NX). Their corresponding biopsy specimens were stained immunohistochemically for Tbeta15, which was then correlated with the clinical outcome in a blinded manner. The median follow-up was 6 years (range 1 to 19) for all of the patients.

RESULTS

The outcomes of the 32 patients can be grouped into three categories: patients with no evidence of disease (n = 11), patients with PSA failure without documented bone failure (n = 11), and patients with PSA failure and documented bone failure (n = 10). Tbeta15 staining intensity strongly correlated with clinical outcome. Of those patients whose specimens stained 3+ (strongest staining), 62% developed bone failure compared with 13% of those patients whose specimens stained 1+ (weakest staining) (P = 0.01). The 5-year freedom from PSA failure was only 25% for those patients with 3+ staining compared with 83% for those with 1+ staining (P = 0.02).

CONCLUSIONS

The results of this pilot study have demonstrated that Tbeta15 staining intensity may be a potentially important marker to identify high-risk patients with moderately differentiated, clinically localized prostate cancer.

Organ-conserving approaches to muscle-invasive bladder cancer: future alternatives to radical cystectomy

In the USA radical surgery remains the golden standard for invasive bladder cancer. Yet in most other areas of surgical oncology the trend of the 1990s has been towards organ conservation with chemoradiation with or without limited local surgery. Patients with breast, oesophageal, anal, lung and larynx cancer are routinely offered conservative therapies as valid options in the management of their diseases but bladder stands apart from the crowd. Evidence is presented here to show that this need not be the case. Four older randomized trials failed to show a survival advantage when immediate cystectomy was compared with radiation followed by salvage cystectomy, if required. Five and 8-year survival rates for clinically staged patients treated by transurethral resection and chemoradiation (trimodality therapy) in several modern, large and mature series show survival rates comparable to those reported in contemporary radical cystectomy series. Eighty per cent of those alive 5 years after chemoradiation still retain their native bladder. Although superficial relapse occurs in 20% of cases, it remains responsive to BCG (Bacilles bilie de Calmette-Guerin) in the manner of de novo superficial disease. Quality-of-life studies show that the retained bladder functions well. At the Massachusetts General Hospital and in the multicentre prospective trials, less than 1% of patients needed cystectomy for bladder morbidity. It is of note that continent diversions may be performed as salvage after contemporary radiation therapy. Trimodality therapy is a novel and contemporary approach that owes little to the radiation treatment offered in the 1970s. While it will never entirely take the place of radical cystectomy, it should be offered as a reasonable alternative to patients with a new diagnosis of bladder cancer. This multidisciplinary approach will allow uro-oncology to keep in step with the oncological vanguard.

An update of combined modality therapy for patients with muscle invading bladder cancer using selective bladder preservation or cystectomy

PURPOSE

We update the results of tri-modality treatment for patients with muscle invading bladder tumors with selection for bladder preservation based on tumor response to induction therapy.

MATERIAL AND METHODS

We reviewed the literature on modern tri-modality bladder preserving approaches using transurethral resection, radiation and concurrent chemotherapy followed by either bladder conservation with careful surveillance for complete responding patients or prompt cystectomy in those whose tumors persist after induction therapy.

RESULTS

The published experiences from 3 centers and 2 prospective trials done by the Radiation Therapy Oncology Group were evaluated for 5-year overall survival of patients selected for bladder preservation or prompt cystectomy (49 to 63%) and for those with a conserved bladder (38 to 43%). The overall 5-year survival rates were comparable to other series of immediate cystectomy based approaches in patients of similar age and presenting with tumors of similar clinical stage. Of patients treated with the bladder preserving approach 20 to 30% cured of muscle invading cancer will subsequently have a new superficial tumor. The superficial tumors have responded well to intravesical drug therapy. Modern bladder preserving treatments usually result in a well functioning bladder without incontinence or significant hematuria. However, concurrent systemic chemotherapy and radiation have the potential for acute morbidity. Presently the ideal candidate for bladder preservation has primary clinical stage T2 tumor, no associated ureteral obstruction, visibly complete transurethral resection and complete response after induction chemoradiation based on endoscopic evaluation including re-biopsy and cytology.

CONCLUSIONS

It is recommended that tri-modality treatment be administered by dedicated multimodality teams. In this country this approach to treatment is available at many of the institutions participating in the Radiation Therapy Oncology Group study. This treatment may be considered a reasonable alternative in patients who are deemed medically unfit for cystectomy and for those who are seeking an alternative to radical cystectomy.

Radiation therapy for clinically localized prostate cancer: a multi-institutional pooled analysis

CONTEXT

Prostate-specific antigen (PSA) evaluation leads to the early detection of both prostate cancer and recurrences following primary treatment. Prostate-specific antigen outcome information on patients 5 or more years following treatment is limited and available mainly as single-institution reports.

OBJECTIVES

To assess the likelihood and durability of tumor control using PSA evaluation 5 or more years after radical external beam radiation therapy and to identify pretreatment prognostic factors in men with early prostate cancer treated since 1988, the PSA era.

DESIGN AND SETTING

Retrospective, nonrandomized, multi-institutional pooled analysis of patients treated with external beam radiation therapy alone between 1988 and 1995 at 6 US medical centers. Follow-up lasted up to a maximum of 9 years. Outcome data were analyzed using Cox regression and recursive partitioning techniques.

PATIENTS

A total of 1765 men with stage T1b, T1c, and T2 tumors treated between 1988 and 1995 with external beam radiation. The majority (58%) of patients were older than 70 years and 24.2% had initial PSA values of 20 ng/mL or higher. A minimum of 2 years of subsequent follow-up was required for participation.

MAIN OUTCOME MEASURE

Actuarial estimates of freedom from biochemical failure.

RESULTS

The 5-year estimates of overall survival, disease-specific survival, and the freedom from biochemical failure are 85.0% (95% confidence interval [CI], 82.5%-87.6%), 95.1% (95% CI, 94.0%-96.2%), and 65.8% (95% CI, 62.8%-68.0%), respectively. The PSA failure-free rates 5 and 7 years after treatment for patients presenting with a PSA of less than 10 ng/mL were 77.8% (95% CI, 74.5%-81.3%), and 72.9% (95% CI, 67.9%-78.2%). Recursive partitioning analysis of initial PSA level, palpation stage, and the Gleason score groupings yielded 4 separate prognostic groups: group 1, included patients with a PSA level of less than 9.2 ng/mL; group 2, PSA level of at least 9.2 but less than 19.7 ng/mL; group 3, PSA level at least 19.7 ng/mL and a Gleason score of 2 to 6; and group 4, PSA level of at least 19.7 ng/mL and a Gleason score of 7 to 10. The estimated rates of survival free of biochemical failure at 5 years are 81 % for group 1, 69% for group 2, 47% for group 3, and 29% for group 4. Of the 302 patients followed up beyond 5 years who were free of biochemical disease, 5.0% relapsed from the fifth to the eighth year.

CONCLUSIONS

Estimated PSA control rates in this pooled analysis are similar to those of single institutions. These rates indicate the probability of success for subsets of patients with tumors of several prognostic category groupings. These results represent a multi-institutional benchmark for evidence-based counseling of prostate cancer patients about radiation treatment.

The long-term effect on PSA values of incidental prostatic irradiation in patients with pelvic malignancies other than prostate cancer

PURPOSE

To determine the effect of external beam radiation therapy on serum prostate-specific antigen (PSA) production by the benign prostate.

METHODS AND MATERIALS

We studied a cohort of 24 men receiving treatment for cancer of the bladder or rectum. The radiation fields in all cases encompassed the prostate gland, and none of the patients were known to have prostate cancer. All patients had 2 or more PSA estimations obtained in the years following their radiation treatment. A second group of 46 patients who had undergone radical external beam radiation therapy for prostate cancer and who were clinically disease free 8-22 years later were also observed, with a median of 5.8 years of PSA observations.

RESULTS

Only 3 of the 24 patients in the first group showed a significant rise of > 0.2 ng/ml in their serum PSA levels, with a median of 3.3 years follow-up from the first PSA test. Seven of 24 showed progressive declines, and 14 of 24 showed steady levels. The median PSA for this group was < or = 0.5 ng/ml. Only 6 of the 46 in the second group showed a PSA rise of > 0.2 ng/ml. Thirty-four had stable values, and 6 had further declines. Again, the median PSA for the entire group was < or = 0.5 ng/ml.

CONCLUSION

Recovery of prostatic secretory function is an uncommon event after external beam radiation. The concern that this might significantly confound new definitions of biochemical failure after radical radiation for prostate cancer that are based on progressively rising PSA values thus appears to be unfounded.

A phase I/II trial of transurethral surgery combined with concurrent cisplatin, 5-fluorouracil and twice daily radiation followed by selective bladder preservation in operable patients with muscle invading bladder cancer

PURPOSE

We describe a protocol designed to evaluate the use of twice daily radiation used together with cisplatin and 5 fluorouracil (5-FU) in the treatment of operable transitional cell carcinoma of the bladder with potential bladder preservation.

MATERIALS AND METHODS

A total of 18 consecutive patients with T2-T4a bladder tumors underwent as complete a transurethral resection as possible, which was visibly complete in 14 cases. They then received twice daily radiation and infusion cisplatin and 5-FU during an induction phase. No therapy was given for 3 weeks, following which patients were reevaluated cystoscopically. Cases of clinical complete response by biopsy and cytology were consolidated with further chemotherapy/radiation using the same chemotherapeutic agents and radiation schedule. Patients who had incomplete responses were advised to undergo an immediate radical cystectomy. Of the 18 patients 15 subsequently received 3 cycles of adjuvant chemotherapy, consisting of methotrexate, cisplatin and vinblastine. Median followup for the entire group is 32 months.

RESULTS

Of the 18 patients 14 had no detectable tumor after induction therapy. Of the 4 patients with persistent tumor 2 underwent radical cystectomy and 2 refused cystectomy, 1 of whom was treated with partial cystectomy and the other with consolidation chemotherapy/radiation. The actuarial overall survival at 3 years was 83%. The chance of a patient being alive at 3 years with a native bladder was 78%. No patient required cystectomy for hematuria or bladder shrinkage. Three patients in whom superficial tumors developed were treated successfully with bacillus Calmette-Guerin. Small bowel obstruction in 1 case was corrected surgically.

CONCLUSIONS

This pilot study demonstrates a high rate of response to this combined chemotherapy/radiation regimen in conjunction with a visibly complete transurethral resection. Reevaluation after a short induction phase allows for the early selection of patients with persistent disease for radical cystectomy.

Phase III trial of neoadjuvant chemotherapy in patients with invasive bladder cancer treated with selective bladder preservation by combined radiation therapy and chemotherapy: initial results of Radiation Therapy Oncology Group 89-03

PURPOSE

To assess the efficacy of neoadjuvant methotrexate, cisplatin, and vinblastine (MCV) chemotherapy in patients with muscle-invading bladder cancer treated with selective bladder preservation.

PATIENTS AND METHODS

One hundred twenty-three eligible patients with tumor, node, metastasis system clinical stage T2 to T4aNXMO bladder cancer were randomized to receive (arm 1, n=61 ) two cycles of MCV before 39.6-Gy pelvic irradiation with concurrent cisplatin 100 mg/m2 for two courses 3 weeks apart. Patients assigned to arm 2 (n=62) did not receive MCV before concurrent cisplatin and radiation therapy. Tumor response was scored as a clinical complete response (CR) when the cystoscopic tumor-site biopsy and urine cytology results were negative. The CR patients were treated with an additional 25.2 Gy to a total of 64.8 Gy and one additional dose of cisplatin. Those with less than a CR underwent cystectomy. The median follow-up of all patients who survived is 60 months.

RESULTS

Seventy-four percent of the patients completed the protocol with, at most, minor deviations; 67% on arm 1 and 81% on arm 2. The actuarial 5-year overall survival rate was 49%; 48% in arm 1 and 49% in arm 2. Thirty-five percent of the patients had evidence of distant metastases at 5 years; 33% in arm 1 and 39% in arm 2. The 5-year survival rate with a functioning bladder was 38%, 36% in arm 1 and 40% in arm 2. None of these differences are statistically significant.

CONCLUSION

Two cycles of MCV neoadjuvant chemotherapy were not shown to increase the rate of CR over that achieved with our standard induction therapy or to increase freedom from metastatic disease. There was no impact on 5-year overall survival.

Management of carcinoma of the bladder

Carcinoma of the bladder (CaB) is a common tumor of the genitourinary tract. In the United States in 1997, CaB was second in frequency of occurrence and third in mortality among genitourinary tumors. This tumor has a well-documented history of environmental and industrial causative factors. The strongest etiologic risk factors include the use of tobacco, which is thought to be responsible for half of the CaB diagnosed in men in the United States, and some arylamines. In the past 30 years, there has been major improvement in the survival of patients with this disease. Multiple factors were responsible for this accomplishment and they include: 1) better understanding of the natural history of CaB, 2) development of immunohistochemical analysis helpful in defining prognostic factors, 3) improved imaging and nonimaging diagnostic modalities helpful in making earlier diagnosis and better defining the true anatomical extent of the tumor, 4) development of more effective therapy for carcinoma in situ, 5) major improvement in surgical techniques resulting in better treatment outcomes, and 6) the wide use of adjuvant chemotherapy. Major stress has been placed on the quality of life of patients treated for CaB. Quality of life was improved by optimizing surgical, radiation, and medical treatment techniques. The two most important factors producing this quality-of-life improvement include: 1) the use of organ-preserving therapy in properly selected patients that involves the use of a multimodality therapeutic approach with transurethral resection, radiation therapy, and chemotherapy; and 2) the ability to treat selected men and women with radical cystectomy followed by orthotopic reconstruction that allows patients nearly physiologic voiding. Current research efforts are directed toward better patient selection for appropriate therapy which is expected to increase patient survival and improve quality of life. Of particular importance in the selection of this optimal therapy in patients with CaB is a wide application in the clinical practice of important recent advances in molecular genetics.

Radiation-based approaches to the management of T3 prostate cancer

Locally advanced prostate cancer is rarely cured by conventional external beam radiation alone. Although occult micrometastatic disease is common, so is locally persistent tumor. This may provide the source of symptomatic local recurrence or metastases in the future. Efforts to improve local control through radiation dose escalation and through the use of neoadjuvant androgen suppression are showing promise. Adjuvant androgen suppression is also under study for those at highest risk of disseminated disease.

Invasive bladder cancer: treatment strategies using transurethral surgery, chemotherapy and radiation therapy with selection for bladder conservation

PURPOSE

Combined modality therapy has become the standard oncologic approach to achieve organ preservation in many malignancies.

METHODS AND MATERIALS

Although radical cystectomy has been considered as standard treatment for invasive bladder carcinoma in the United States, good results have been recently reported from several centers using multimodality treatment, particularly in patients with clinical T2 and T3a disease who do not have a ureter obstructed by tumor.

RESULTS

The components of the combined treatment are usually transurethral resection of the bladder tumor (TURBT) followed by concurrent chemotherapy and radiation therapy. Following an induction course of therapy a histologic response is evaluated by cystoscopy and rebiopsy. Clinical "complete responders" (tumor site rebiopsy negative and urine cytology with no tumor cells present) continue with a consolidation course of concurrent chemotherapy and radiation. Those patients not achieving a clinical complete response are recommended to have an immediate cystectomy. Individually the local monotherapies of radiation, TURBT, or multidrug chemotherapy each achieve a local control rate of the primary tumor of from 20 to 40%. When these are combined, clinical complete response rates of from 65 to 80% can be achieved. Seventy-five to 85% of the clinical complete responders will remain with bladders free of recurrence of an invasive tumor.

CONCLUSIONS

Bladder conservation trials using combined modality treatment approaches with selection for organ conservation by response of the tumor to initial treatment report overall 5-year survival rates of approximately 50%, and a 40-45% 5-year survival rate with the bladder intact. These modern multimodality bladder conservation approaches offer survival rates similar to radical cystectomy for patients of similar clinical stage and age. Bladder-conserving therapy should be offered to patients with invasive bladder carcinoma as a realistic alternative to radical cystectomy by experienced multimodality teams of urologic oncologists.

Treatment strategies using transurethral surgery, chemotherapy, and radiation therapy with selection that safely allows bladder conservation for invasive bladder cancer

Combined modality therapy with the goal of effecting cure and achieving organ preservation has become the standard oncological approach in many malignancies. Although radical cystectomy has been considered the standard treatment for invasive carcinoma of the bladder, equivalent results have been achieved using combined modality treatment in selected patients, particularly those with T2 and T3a disease without obstructed ureters. Effective combined modality treatment consists of three treatment modalities: (1) transurethral resection of the bladder tumor (TURBT), followed by concurrent (2) chemotherapy, and (3) radiation. Following induction therapy, histologic response is evaluated by cystoscopy and biopsy. Clinical complete responders continue with concurrent chemotherapy and irradiation. Those patients not achieving a clinical complete response are advised to undergo cystectomy. Individually the local monotherapies of radiation, TURBT, or systemic chemotherapy each achieve a local control rate of 20% to 40%. When they are combined, complete response rates of 70-80% are achieved and 85% of these will remain free of invasive recurrence in the bladder. Bladder preservation trials using combined modality treatment approaches with selection for organ conservation by response to initial treatment report an overall 5-year survival rate of approximately 50%, and they have achieved a 40% to 45% 5-year survival rate with the bladder intact. Modern multi-modality bladder preservation approaches offer survival rates similar to radical cystectomy, for patients of similar clinical stage and age, and an improved quality of life by allowing a majority of patients to retain their own fully functional bladder. Bladder conservation therapy may be offered to selected patients with bladder cancer as one alternative to radical cystectomy, and its use should be by experienced multi-modality teams of urologic oncologists.

The case for radiotherapy with or without chemotherapy in high-risk superficial and muscle-invading bladder cancer

The standard treatment for superficial high-grade bladder cancer is transurethral resection with or without subsequent intravesical therapy. Although a few series have reported good local control rates for T1 tumors, using either external beam irradiation or brachytherapy, this does not represent the standard of care in the United States. External beam radiation may be attempted in patients whose tumors cannot be resected transurethrally and who refuse cystectomy. The case for radiotherapy with or without chemotherapy is far stronger in muscle-invading cancers. Overall survival rates around 50% have been reported in larger series from a number of major centers. Most of these 5-year survivors retain their native bladders. The bladder morbidity of such an approach is very low. There are several studies currently active to determine the most appropriate sequence and combination of drugs and radiation.

Adjuvant and salvage irradiation following radical prostatectomy for prostate cancer

PURPOSE

We performed a retrospective analysis to assess the durability of benefit derived from irradiation after prostatectomy for pT3N0 disease, and the possibility of cure.

METHODS AND MATERIALS

We studied 88 patients who were irradiated after prostatectomy and had available prostate specific antigen (PSA) data, no known nodal or metastatic disease, no hormonal treatment, and follow-up of at least 12 months from surgery. Forty patients received adjuvant therapy for a high risk of local failure with undetectable PSA. Forty-eight patients received salvage therapy for elevated PSA levels. Mean follow up was 44 months from date of surgery and 31 months from irradiation. Biochemical failure was strictly defined as a confirmed rise in PSA of >10%, or as the ability to detect a previously undetectable PSA value.

RESULTS

After salvage irradiation, 69% of patients attained an undetectable PSA. Eighty-eight percent of adjuvant patients were biochemically and clinically free of disease (bNED) at 3 years from prostatectomy. Sixty-eight percent of those receiving salvage irradiation were bNED 3 years after surgery. On univariate analysis, treatment group (adjuvant or salvage), pre-operative PSA, and the status of seminal vesicles were significant prognostic factors. The extent of PSA elevation in the salvage group was also significant. We did not demonstrate a significant difference between those salvage patients referred for persistently elevated PSA as compared to those with a late rise in PSA. On multivariate analysis, the only significant predictor of outcome was treatment group, with adjuvant irradiation having better outcome than salvage.

CONCLUSION

More than two-thirds of this group of patients remain biochemically disease free at 3 years following irradiation, attesting to a number of potential cures. For patients with stage pT3N0 prostate cancer following radical prostatectomy, our data support the use of either routine postoperative adjuvant irradiation or close PSA follow-up with early salvage treatment.

Phase III trial of androgen suppression using goserelin in unfavorable-prognosis carcinoma of the prostate treated with definitive radiotherapy: report of Radiation Therapy Oncology Group Protocol 85-31

PURPOSE

Although androgen suppression results in a tumor response/remission in the majority of patients with carcinoma of the prostate, its potential value as an adjuvant has not been substantiated.

MATERIALS AND METHODS

In 1987, the Radiation Therapy Oncology Group (RTOG) initiated a randomized phase III trial of adjuvant goserelin in definitively irradiated patients with carcinoma of the prostate. A total of 977 patients had been accessioned to the study. Of these, 945 remained analyzable: 477 on the adjuvant arm and 468 on the observation arm.

RESULTS

Actuarial projections show that at 5 years, 84% of patients on the adjuvant goserelin arm and 71% on the observation arm remain without evidence of local recurrence (P < .0001). The corresponding figures for freedom from distant metastases and disease-free survival are 83% versus 70% (P < .001) and 60% and 44% (P < .0001). If prostate-specific antigen (PSA) level greater than 1.5 ng is included as a failure (after > or = 1 year), the 5-year disease-free survival rate on the adjuvant goserelin arm is 53% versus 20% on the observation arm (P < .0001). The 5-year survival rate (for the entire population) is 75% on the adjuvant arm versus 71% on the observation arm (P = .52). However, in patients with centrally reviewed tumors with a Gleason score of 8 to 10, the difference in actuarial 5-year survival (66% on the adjuvant goserelin arm v 55% on the observation arm) reaches statistical significance (P = .03).

CONCLUSION

Application of androgen suppression as an adjuvant to definitive radiotherapy has been associated with a highly significant improvement in local control and freedom from disease progression. At this point, with a median follow-up time of 4.5 years, a significant improvement in survival has been observed only in patients with centrally reviewed tumors with a Gleason score of 8 to 10.

Neoadjuvant androgen suppression with radiation in the management of locally advanced adenocarcinoma of the prostate: experimental and clinical results

Conventional radiotherapy has been a standard treatment for the management of locally advanced T2c-4 prostatic carcinoma for over 2 decades. The routine use of serum PSA in follow-up makes it clear that > 80% of these patients will show evidence of failure by 10 years. Rebiopsy of those with a rising PSA shows locally persistent disease in the majority of cases. Increasing the radiation dose applied to the prostate increases local control but at the risk of higher morbidity. Experimental data using the Shionogi tumor mouse model suggest a potential gain from neoadjuvant androgen suppression without any increase in normal tissue morbidity. Two randomized trials comparing neoadjuvant androgen suppression prior to radiation therapy with radiation alone in humans show considerable short-term gains in local control and disease-free survival but mature data are still awaited. It is currently unknown whether the positive interaction between radiation and androgen suppression is synergistic or simply additive.

Bladder preservation by combined modality therapy for invasive bladder cancer

PURPOSE

To update the efficacy of a selective multimodality bladder-preserving approach by transurethral resection (TURBT), systemic chemotherapy, and radiation therapy.

PATIENTS AND METHODS

From 1986 through 1993, 106 patients with muscle-invading clinical stage T2 to T4a,Nx,M0 bladder cancer were treated with induction by maximal TURBT and two cycles of chemotherapy (methotrexate, cisplatin, vinblastine [MCV]) followed by 39.6-Gy pelvic irradiation with concomitant cisplatin. Patients with a negative postinduction therapy tumor site biopsy and cytology (a T0 response, 70 patients) plus those with less than a T0 response but medically unfit for cystectomy (six patients), received consolidative chemoradiation to a total of 64.8 Gy. Surgical candidates with less than a T0 response (13 patients) and patients who could not tolerate the chemoradiation (six patients) went to immediate cystectomy. The median follow-up duration is 4.4 years.

RESULTS

The 5-year actuarial overall survival and disease-specific survival rates of all patients are 52% and 60%, respectively. For clinical stage T2 patients, the actuarial overall survival rate is 63%, and for T3-4, 45%. Thirty-six patients (34%) underwent cystectomy, all with evidence of tumor activity, including 17 with an invasive recurrence. The 5-year overall survival rate with an intact functioning bladder is 43%. Among 76 patients who completed bladder-preserving therapy, the 5-year rate of freedom from an invasive bladder relapse is 79%. No patient required cystectomy for treatment-related bladder morbidity.

CONCLUSION

Combined modality therapy with TURBT, chemotherapy, radiation, and selection for organ-conservation by response has a 52% overall survival rate. This result is similar to cystectomy-based studies for patients of similar age and clinical stages. The majority of the long-term survivors retain fully functional bladders.

Organ-sparing treatment of bladder cancer: an innovative approach

Muscle-invasive carcinoma of the urinary bladder is a highly malignant disease with a rapid doubling time and a propensity for distant metastasis. Although radical cystectomy has been the treatment of choice in the United States, limited tumor resection followed by chemotherapy and radiation therapy, with preservation of a normally functioning bladder, is an alternative approach of significant usefulness. In carefully selected patients, such treatment offers a good chance of long-term cure and survival equal to that associated with cystectomy. This combined-modality approach remains investigational and requires a multidisciplinary team including a urologic surgeon, a radiation oncologist and a medical oncologist.

p53 status and prognosis of locally advanced prostatic adenocarcinoma: a study based on RTOG 8610

BACKGROUND

The p53 tumor suppressor gene (also known as TP53) is one of the most frequently mutated genes in human cancer. Several studies have shown that p53 mutations are infrequent in prostate cancer and are associated with advanced disease.

PURPOSE

We assessed the prognostic value of identifying abnormal p53 protein expression in the tumors of patients with locally advanced prostate cancer who were treated with either external-beam radiation therapy alone or total androgen blockade before and during the radiation therapy.

METHODS

The study population consisted of a subset of patients entered in Radiation Therapy Oncology Group protocol 8610 ("a phase III trial of Zoladex and flutamide used as cytoreductive agents in locally advanced carcinoma of the prostate treated with definitive radiotherapy"). Immunohistochemical detection of abnormal p53 protein in pretreatment specimens (i.e., needle biopsies or transurethral resections) was achieved by use of the monoclonal anti-p53 antibody DO7; specimens in which 20% or more of the tumor cell nuclei showed positive immunoreactivity were considered to have abnormal p53 protein expression. Associations between p53 protein expression status and the time to local progression, the incidence of distant metastases, progression-free survival, and overall survival were evaluated in univariate (logrank test) and multivariate (Cox proportional hazards model) analyses. Reported P values are two-sided.

RESULTS

One hundred twenty-nine (27%) of the 471 patients entered in the trial had sufficient tumor material for analysis. Abnormal p53 protein expression was detected in the tumors of 23 (18%) of these 129 patients. Statistically significant associations were found between the presence of abnormal p53 protein expression and increased incidence of distant metastases (P = .04), decreased progression-free survival (P = .03), and decreased overall survival (P = .02); no association was found between abnormal p53 protein expression and the time to local progression (P = .58). These results were independent of the Gleason score and clinical stage. A significant treatment interaction was detected with respect to the development of distant metastases: Among patients receiving both radiation therapy and hormone therapy, those with tumors exhibiting abnormal p53 protein expression experienced a reduced time to the development of distant metastases (P = .001); for patients treated with radiation therapy alone, the time to distant metastases was unrelated to p53 protein expression status (P = .91).

CONCLUSIONS

Determination of p53 protein expression status yield significant, independent prognostic information concerning the development of distant metastases, progression-free survival, and overall survival for patients with locally advanced prostate cancer who are treated primarily with radiation therapy.

IMPLICATIONS

The interaction of radiation therapy plus hormone therapy and abnormal p53 protein expression may provide a clinical link to experimental evidence that radiation therapy and/or hormone therapy act, at least in part, by the induction of apoptosis (a cell death program) and suggests that this mechanism may be blocked in patients whose tumors have p53 mutations.

Opportunities with combined modality therapy for selective organ preservation in muscle-invasive bladder cancer

Combined-modality therapy for organ preservation represents an appropriate alternative to radical surgery in the management of several malignant diseases. The standard therapy for muscle-invasive bladder cancer in the United States has been radical cystectomy. Although the sequelae of radical surgery have been ameliorated somewhat by techniques for the construction of orthotopic bladders, the ideal therapy should both cure the patient of cancer and maintain a functioning natural bladder. Years of experience in Europe and Canada with bladder preservation using radiation therapy are documented. Advances in transurethral surgery technique and in the combination of radiation and chemotherapy have led to safe and effective regimens for patients with bladder cancer. Several recent trials with combined-modality therapy have established this treatment as a viable alternative to radical cystectomy in selected patients.

Conformal irradiation of the prostate: estimating long-term rectal bleeding risk using dose-volume histograms

PURPOSE

Dose-volume histograms (DVHs) may be very useful tools for estimating probability of normal tissue complications (NTCP), but there is not yet an agreed upon method for their analysis. This study introduces a statistical method of aggregating and analyzing primary data from DVHs and associated outcomes. It explores the dose-volume relationship for NTCP of the rectum, using long-term data on rectal wall bleeding following prostatic irradiation.

METHODS AND MATERIALS

Previously published data were reviewed and updated on 41 patients with Stages T3 and T4 prostatic carcinoma treated with photons followed by perineal proton boost, including dose-volume histograms (DVHs) of each patient's anterior rectal wall and data on the occurrence of postirradiation rectal bleeding (minimum FU > 4 years). Logistic regression was used to test whether some individual combination of dose and volume irradiated might best separate the DVHs into categories of high or low risk for rectal bleeding. Further analysis explored whether a group of such dose-volume combinations might be superior in predicting complication risk. These results were compared with results of the "critical volume model," a mathematical model based on assumptions of underlying radiobiological interactions.

RESULTS

Ten of the 128 tested dose-volume combinations proved to be "statistically significant combinations" (SSCs) distinguishing between bleeders (14 out of 41) and nonbleeders (27 out of 41), ranging contiguously between 60 CGE (Cobalt Gray Equivalent) to 70% of the anterior rectal wall and 75 CGE to 30%. Calculated odds ratios for each SSC were not significantly different across the individual SSCs; however, analysis combining SSCs allowed segregation of DVHs into three risk groups: low, moderate, and high. Estimates of probabilities of normal tissue complications (NTCPs) based on these risk groups correlated strongly with observed data (p = 0.003) and with biomathematical model-generated NTCPs.

CONCLUSIONS

There is a dose-volume relationship for rectal mucosal bleeding in the region between 60 and 75 CGE; therefore, efforts to spare rectal wall volume using improved treatment planning and delivery techniques are important. Stratifying dose-volume histograms (DVHs) into risk groups, as done in this study, represents a useful means of analyzing empirical data as a function of hetereogeneous dose distributions. Modeling efforts may extend these results to more heterogeneous treatment techniques. Such analysis of DVH data may allow practicing clinicians to better assess the risk of various treatments, fields, or doses, when caring for an individual patient.

Conservative surgery, patient selection, and chemoradiation as organ-preserving treatment for muscle-invading bladder cancer

Multimodality organ-sparing treatment has, during the last decade, become the standard of care for many common malignancies. In appropriately selected patients with muscle-invading bladder cancer, bladder-preserving treatment combining surgical transurethral resection (TUR) with chemoradiation therapy offers a chance for long-term cure and survival equal to cystectomy, while also affording a 60% to 70% chance of maintaining a normally functioning bladder. Selection criteria helpful in determining appropriate patients for bladder preservation include such variables as small tumor size, that a visibly complete TUR is possible, the absence of hydronephrosis and that a complete response (CR) to induction chemoradiotherapy was achieved. Selecting patients based on response to induction therapy allows for prompt cystectomy if residual disease is found or for prompt consolidation chemoradiotherapy if a CR with induction therapy is achieved. Bladder-preserving treatment usually results in a normally functioning bladder without incontinence or hematuria for stage T2 and T3a patients. Stage T3b-T4 patients are locally controlled less frequently using these techniques. However, no data exist to suggest that patients with more advanced disease are in any way disadvantaged by preoperative chemoradiotherapy as an attempt at bladder conservation. Patients require close urological surveillance as do any patients with superficial bladder cancer who are being treated conservatively. As studies addressing the possibility of organ preservation continue to show positive results, more patients will become informed about and will be offered selective bladder-sparing approaches as one-treatment option.