Re: Vikram, B., The PSA conundrum. [Radiother Oncol, 2004. 71(1): p. 1-2].
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Publications and source records attributed to Padraig Warde.
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All patients who undergo curative therapy for prostate cancer should be followed for a prolonged period of time to determine tumor control and treatment toxicity for quality assurance purposes. Follow-up duties may be reasonably shared between the oncologist and the family doctor or urologist: however, it is probable that some follow-up information specific to the irradiated patient will be lost unless the oncologist maintains regular contact with the patient, especially in the first 5 years of follow-up when late radiation effects are most likely to appear. There is no strong evidence that patients stop being at risk for recurrence at any time after treatment, and because PSA testing is an accurate, simple, and inexpensive method of determining post-RT tumor status, it is recommended that periodic PSA measurements be continued for life. In the absence of a rising PSA, all other tests and visits are unnecessary to determine post-RT tumor control. Because DRE has been shown to be of limited utility in follow-up of irradiated patients, it should be possible to effectively follow patients remotely. This could be done by asking patients to have PSA tests done, forward the results to their physicians, and report treatment toxicity when it occurs. Only abnormal results would trigger an office visit. This strategy is being evaluated in clinical trials. The alternative is to delegate the follow-up to the primary-care physician with guidelines as to when referral back is required. Follow-up frequency, and the most beneficial follow-up investigations vary from scenario to scenario, and are influenced by the likelihood of relapse, time to relapse, and planned intervention. These decisions are influenced in turn by the initial presentation--either with high or low risk factors--and by the patient's general state of health at completion of EBRT. Effective follow-up also requires active patient cooperation that only can be achieved after discussion of the goals of follow-up with the patient and with the patient's full understanding of the process. The follow-up strategy proposed in Fig. 1 is most suitable for a fit patient with low or intermediate risk factors who wishes to consider all salvage options should he relapse, or for the high-risk individual in situations in which the probability of systemic relapse is of major concern. Young patients with very adverse risk factors may benefit from even closer follow-up in the early years after EBRT and the elderly or frail may require only occasional visits to record or treat treatment toxicity and to ensure clinical non-progression.
PURPOSE: To assess the adequacy of coverage of gross tumor volume (GTV) with traditional two dimensional (2D) radiation therapy (RT) planning in patients with nasopharyngeal cancer (NPC). MATERIALS AND METHODS: The study comprised 94 of 179 patients treated with definitive RT between 1993 and 1997. The inclusion requirement was the availability of a digitally archived pretreatment magnetic resonance imaging. The digital images were used to record the precise location of the GTV in the sagittal plane. As a separate procedure, sagittal dose distributions for each treatment phase were created by digitizing the simulation field parameters into treatment planning software without knowledge of the GTV. The location of the GTV and dose distribution in the sagittal plane were superimposed on each other and GTV coverage by the 50, 90 and 95% isodose lines determined for each phase of treatment. RESULTS: The 1997 tumour node metastasis (TNM) stage distribution was: 7 (8%) stage I, 16 (16%) stage II, 30 (32%) stage III and 41 (44%) stage IV. Median follow-up was 4.4 years. Median primary dose was 66 Gy. The actuarial 5-year overall survival, disease free survival and local relapse free rates were 88, 54 and 66%, respectively. The GTV was covered by the 50, 90 and 95% isodose lines for all phases of the multiphase plan in only 53, 20 and 9% of patients, respectively. The GTV was more likely to be undercovered in the latter phases of the plan particularly in those patients with advanced T category. CONCLUSION: 2D RT planning has significant limitations in achieving adequate GTV coverage in NPC. We strongly recommend 3D planning using either conformal techniques of dose delivery or intensity modulated radiation therapy for the treatment of these patients.
PURPOSE: p16 is an important inhibitor of cell cycle progression; absence of p16 can thus result in increased cellular proliferation. In nasopharyngeal carcinoma (NPC), absence of p16 has been reported in association with presence of the EBV and pRb. We therefore examined p16, pRb, and EBV-encoded RNA (EBER) expression in biopsy specimens from 84 patients with newly diagnosed NPC, who were treated primarily with curative radiation therapy. Our objective was to determine whether there was a correlation between these parameters and clinical outcome in NPC. EXPERIMENTAL DESIGN: Sections were cut from archival formalin-fixed, paraffin-embedded tumor blocks from NPC patients. p16 and pRb expression were determined using polyclonal and monoclonal antibodies, respectively. The presence of EBV was determined by in situ hybridization for EBER. The percentage of positively staining tumor nuclei was scored for p16 or pRb immunoreactivity. Relative intensity and proportion of cells with EBER signals were also documented. RESULTS: p16 expression was reduced (</=5% positive immunoexpression) in 59 of 84 (70%) NPC samples; in contrast, pRb was observed in all (100%) tumors. EBER signals were detected in 67 of 83 (81%) NPC specimens. There was a weak correlation between EBER presence and loss of p16 (P = 0.1). Using a Cox regression model controlling for known prognostic parameters, such as age, weight loss, and tumor stage, complete absence of p16 expression (0%, i.e., no immunostaining identified throughout the specimen) was associated with an inferior overall survival rate (P = 0.022). In addition, EBER-positive NPC was strongly associated with improved overall survival (P = 0.005) as reported previously (Shi et al., Cancer, 94: 1997, 2002). CONCLUSION: These results provide the first evidence suggesting that inactivation of p16 appears to be a significant predictor for poor overall survival in NPC. Given that reduced p16 expression is observed in the majority of patients with NPC, this indicates that therapeutic strategies targeting the p16 pathway may be a biologically rational approach for NPC. The favorable prognostic value of EBER suggests that future clinical trials with NPC should consider stratifying for EBER status.
PURPOSE: Several management options are available to patients with stage I seminoma, including adjuvant radiotherapy, surveillance, and adjuvant chemotherapy. We performed a pooled analysis of patients from the four largest surveillance studies to better delineate prognostic factors associated with disease progression. PATIENTS AND METHODS: Individual patient data were obtained from each center (Princess Margaret Hospital, Danish Testicular Cancer Study Group, Royal Marsden Hospital, and Royal London Hospital) for 638 patients. Tumor characteristics (size, histologic subtype, invasion of rete testis, and tumor invasion into small vessels [SVI]) as well as age at diagnosis were analyzed for prognostic importance for relapse. RESULTS: With a median follow-up of 7.0 years (range, 0.02 to 17.5 years), 121 relapses were observed for an actuarial 5-year relapse-free rate (RFR) of 82.3%. On univariate analysis, tumor size (RFR: 4 cm, 76%; P =.003), rete testis invasion (RFR: 86% [absent] v 77% [present], P =.003), and the presence of SVI (RFR: 86% [absent] v 77% [present], P =.038) were predictive of relapse. On multivariate analysis, tumor size ( 4 cm, hazard ratio 2.0; 95% confidence interval [CI], 1.3 to 3.2) and invasion of the rete testis (hazard ratio 1.7; 95% CI, 1.1 to 2.6) remained as important predictors for relapse. CONCLUSION: We have identified size of primary tumor and rete testis invasion as important prognostic factors for relapse in patients with stage I seminoma managed with surveillance. This information will allow patients and clinicians to choose management based on a more accurate assessment of an individual patient's risk of relapse. In addition, it will allow clinicians to tailor follow-up protocols based on risk of occult disease.
PURPOSE: To test the hypothesis that the use of oral pilocarpine during and after radiotherapy (RT) for head-and-neck cancer would reduce the symptoms of post-RT xerostomia. METHODS AND MATERIALS: One hundred thirty patients were randomized in a double-blind method to receive either pilocarpine (5-mg tablets) or placebo three times daily starting on Day 1 of RT and continuing for 1 month after treatment. The eligibility criteria included a planned dose of >50 Gy as radical or postoperative RT for head-and-neck cancer, with at least 50% of both parotid glands included in the treatment fields. The primary outcome measure was the severity of xerostomia as assessed by a patient-completed linear analog scale 3 months after RT. Secondary outcome measures included quality of life during therapy (as assessed by the McMaster University Head-and-Neck Questionnaire) and severity of mucositis during RT (as assessed using Radiation Therapy Oncology Group scales). RESULTS: No difference was observed between the pilocarpine-treated patients and the placebo group in the severity of xerostomia score as assessed by linear analog scale at baseline and 1, 3, and 6 months after treatment (repeated measures analysis, p = 0.92). No difference was apparent in the severity of mucositis during RT; 56.3% of patients receiving pilocarpine had Grade III/IV mucositis compared with 50.8% treated with placebo. No difference in quality of life was noted between the treatment groups during or after RT. The questionnaire score at 3 months after RT was 5.0 (SD 1.0). in the pilocarpine group and 4.9 (SD 0.9) in the placebo group. CONCLUSION: We were unable to detect a beneficial effect of pilocarpine on RT-induced xerostomia when administered during RT for head-and-neck cancer.
BACKGROUND: We did a randomised phase III trial comparing external irradiation alone and external irradiation combined with an analogue of luteinising-hormone releasing hormone (LHRH) to investigate the added value of long-term androgen suppression in locally advanced prostate cancer. METHODS: Between 1987 and 1995, 415 patients were randomly assigned radiotherapy alone or radiotherapy plus immediate androgen suppression. Eligible patients had T1-2 tumours of WHO grade 3 or T3-4 N0-1 M0 tumours; the median age of participants was 71 years (range 51-80). In both treatment groups, 50 Gy radiation was delivered to the pelvis over 5 weeks, and 20 Gy over 2 weeks as a prostatic boost. Goserelin (3.6 mg subcutaneously every 4 weeks) was started on the first day of irradiation and continued for 3 years; cyproterone acetate (150 mg orally) was given for 1 month starting 1 week before the first goserelin injection. The primary endpoint was clinical disease-free survival. Analyses were by intention to treat. FINDINGS: 412 patients had evaluable data, with median follow-up of 66 months (range 1-126). 5-year clinical disease-free survival was 40% (95% CI 32-48) in the radiotherapy-alone group and 74% (67-81) in the combined-treatment group (p=0.0001). 5-year overall survival was 62% (52-72) and 78% (72-84), respectively (p=0.0002) and 5-year specific survival 79% (72-86) and 94% (90-98). INTERPRETATION: Immediate androgen suppression with an LHRH analogue given during and for 3 years after external irradiation improves disease-free and overall survival of patients with locally advanced prostate cancer.
BACKGROUND: To derive a better understanding of the biologic behavior of nasopharyngeal carcinoma (NPC), the authors evaluated a number of molecular variables to address the hypothesis that p53 dysfunction in NPC is associated with Epstein-Barr virus (EBV), increased tumor angiogenesis, lower likelihood of apoptosis, and poorer clinical outcome. MATERIALS: The biopsy samples from 87 NPC patients were obtained and sections were made to detect EBV, using in-situ hybridization; the authors used immunohistochemistry to assess p53, p21(WAF1/CIP1) expression, and microvessel density count (MVD). In situ end labelling was used to evaluate apoptosis and necrosis. Analyses were conducted on the association between each of these variables as well as clinical outcome, including survival and local control. RESULTS: There was a highly significant association between EBV-encoded RNA (EBER) positivity with p53 over-expression in that only 1 out of 32 p53 over-expressing tumors was EBER negative, as opposed to 19 out of 48 p53 negative tumors being EBER negative (P = 0.001). In addition, EBER positivity was highly associated with World Health Organization (WHO) type 3 NPC, Asian/Chinese ethnicity, a lower apoptotic index, and p21 over-expression. p53 over-expression was associated with a higher MVD count. Controlling for age and nodal status, EBER positivity was associated with both improved overall survival (P = 0.02), and disease-free survival (P = 0.04). In contrast, the presence of tumor necrosis was associated with an inferior local control (P = 0.03). CONCLUSION: p53 protein was over-expressed in approximately one third of NPC samples in the current study, and this correlated significantly with the presence of EBER. Epstein-Barr virus status was also associated with WHO type 3 NPC, Asian/Chinese ethnicity, and induction of p21. The presence of EBV appeared to predict for improved survival, the mechanism of which remains to be elucidated in this biologically complex disease.
OBJECTIVES: To determine the accuracy of clinicians' predictions of life expectancy in patients with localized prostate cancer, when provided with information about age and comorbidity, and to determine whether life expectancy estimates predict the choice of initial treatment. METHODS: A survey was sent by facsimile to 191 Canadian urologists and radiation oncologists asking them to estimate the life expectancy and choose the initial therapy (radical prostatectomy, radiation, or watchful waiting) for 18 patient scenarios: two prostate cancer scenarios, each with three ages and three levels of comorbidity. RESULTS: Life expectancy estimates were accurate within 1 year of the projections of a Markov model for 31% of the clinicians' responses and accurate within 3 years for 67% of the responses. The average prediction error ranged from 2.4 to 5.2 years. The life expectancy was correctly estimated as being greater than or less than 10 years in 82% of responses. Ten years was the minimal life expectancy for recommending surgery and within the range (5 to 15 years) in which radiation was recommended. CONCLUSIONS: Clinicians can use age and comorbidity to predict the life expectancy of patients with localized prostate cancer with a modest degree of overall accuracy, but with sufficient accuracy to use the "10-year rule." Life expectancy estimates are strongly associated with treatment choice. The appropriateness of the 10-year rule remains to be determined.
PURPOSE: To examine the outcome of radiotherapy (RT) alone in patients with advanced nasopharyngeal cancer (NPC) and to compare the results with those reported by the Intergroup study 0099 (IGS) comparing RT to combined modality therapy (CMT). MATERIALS AND METHODS: During the period 1985-1992, 198 NPC patients presenting without distant metastatic disease were treated for cure. Of these, 172 had stage III/IV (UICC 1987, 1992). Planned RT was 2 Gy/day fraction to 60-66 Gy to the primary tumor, with 50 and 60 Gy to the node negative and to palpable nodes, respectively. Outcomes included overall survival (OS) and disease-free survival (DFS), defined from the time of registration at our institution. RESULTS: The TNM categories and other prognostic factors were similar to the IGS, though 80% had stage IV compared to 91% in IGS. The 5 year OS and DFS for the 172 patients with stage III/IV disease were 62 and 48%, respectively, as compared to the IGS results of OS 37% and DFS 29% for RT alone, and OS 67% and DFS 58% for the CMT arm of IGS. When the distribution of adverse prognostic factors was balanced between both studies the comparative results were unchanged. CONCLUSIONS: The early results for RT alone of this single institution experience are superior to those of the IGS control arm (RT), while somewhat inferior to those reported in the chemo-radiotherapy arm. The surprisingly poor outcome of the IGS/RT control arm may have resulted by chance, suggesting the need for a confirmatory randomized trial to fully establish the role of combined chemotherapy and radiation, as used in the IGS.
BACKGROUND AND PURPOSE: The purpose was to develop a systematic review that would address the following questions: (a) when single-modality treatment external-beam radiotherapy is selected as the modality of choice, what is the role of three-dimensional (3D) conformal radiotherapy in treating clinically localized (T1, T2/NO, NX/MO) prostate cancer? The outcomes of interest are biochemical freedom from failure (bNED) rates, clinical recurrence-free survival, disease-specific survival and acute and late toxicity; (b) what is the appropriate dose and fractionation prescription in this clinical setting? MATERIALS AND METHODS: A systematic review of the English published literature was undertaken to provide evidence relevant to the above outcomes. RESULTS: One randomized controlled trial comparing conventional radiotherapy to conformal therapy with dose escalation reported bNED rates. Three additional randomized controlled trials reported acute or chronic late outcome assessments. Additionally, phase II studies of dose escalation in sequential patient cohorts and non-randomized comparative assessments of dose-response and bNED rates in controlled analyses were reviewed. There is convincing evidence from randomized trials that the use of conformal therapy reduces acute and late treatment-related morbidity. There is preliminary evidence suggesting that when external-beam therapy alone is used to treat patients, conformal therapy with dose-escalation is more efficacious than doses of 70Gy. The increased efficacy appears to be predominantly seen in the subset of patients with intermediate-risk disease (PSA 10-20). There is conflicting evidence of the efficacy of dose-escalation in patients with low initial PSA (<10) and in patients with initial PSA greater than 20. Conformal radiotherapy at a dose of 78Gy appears to be relatively safe with no increase in acute or late effects compared with conventional treatment (up to 70Gy) so long as appropriate technological principles are considered. CONCLUSIONS: Patients who have external-beam radiotherapy should be treated using a 3D conformal technique. Patients with intermediate-risk disease (PSA 10-20) who are treated with external-beam radiotherapy alone should be offered doses of 75-78Gy in 180-200cGy fractions.
BACKGROUND AND PURPOSE: There is no consensus on whether the seminal vesicles should be included in the clinical target volume (CTV) for radiotherapy of localized prostate cancer. To inform the debate, we have undertaken a dose-volume histogram (DVH) analysis of the seminal vesicles in patients treated with escalated dose conformal radiation to 'prostate alone'. MATERIAL AND METHODS: Twenty-five consecutive patients receiving conformal radiation to the prostate, to a dose of 75.6 Gy in 42 daily fractions, were studied. The CTV was defined as the prostate only, and the planning target volume (PTV) was defined by a 10 mm margin, except posteriorly where the margin was 7 mm. DVHs were calculated for the entire seminal vesicles, and for 6 mm segments through the seminal vesicles. RESULTS: Incorporating a correction for organ motion, the D90 (minimum dose received by 90% of the volume of interest) for the most inferior 6 mm volume of the seminal vesicles (SV1) ranged from 25 to 70 Gy, and the percentage volume of SV1 receiving 50 Gy ranged from 47-100%. Using a D90 of 50 Gy as a cut-off, eight of the 25 patients had unacceptably low-dose coverage of SV1. CONCLUSIONS: Escalated dose conformal radiation to the 'prostate alone' does not ensure adequate dose coverage of even the most inferior 6 mm of the seminal vesicles. We consider such treatment acceptable in patients at low risk of seminal vesicle involvement (T1/2ab, Gleason < or = 7, PSA < 10 ng/ml). In higher risk patients, if it is deemed necessary to treat the possibility of sub-clinical seminal vesicle involvement, this should be reflected in the definition of the CTV.
Tremendous progress has been made in the treatment of testicular seminoma over the past 25 years. The advent of curative cytotoxic chemotherapy, even for patients with advanced metastatic disease, has led to a paradigm shift toward minimizing additional oncologic therapies and their potential side effects. Despite these advances, controversial issues still exist in managing patients with this disease. Patients with stage I disease can now be managed successfully with close surveillance or postoperative radiotherapy (RT). Although deemed safe, considerable debate persists about surveillance including issues of compliance, cost, and secondary effects of routine RT. Aside from RT, patients with stage I disease also can be managed with one- or 2-dose single-agent carboplatin. Although this appears safe and efficacious, an ongoing randomized study is underway to compare its effectiveness with that of RT. Residual mass after chemotherapy for seminoma is not uncommon and therapeutic options include observation, RT, or retroperitoneal lymphadenectomy. Although most agree that patients with small (<3 cm) or ill-defined masses can be observed, debate persists as to the optimal management of patients with well-defined masses greater than 3 cm. For many years, patients with bulky retroperitoneal disease (>5 cm) were treated with up-front radiotherapy and chemotherapy at relapse. The high failure rate outside the treatment field has now changed this paradigm to one of up-front chemotherapy.
PURPOSE: To retrospectively review the results of conventional dose radical radiotherapy for clinical stage T1 and T2 prostate cancer, and to identify the factors that predict the biochemical relapse-free rate. METHODS: The records were reviewed of 706 hormonally-naïve men with clinical stage T1T2 prostate cancer treated with radical radiotherapy (RT) between 1987-1994 at the Princess Margaret Hospital. The median prostate RT dose was 65 Gy in 35 fraction (range 52 Gy in 20 fractions to 67 Gy in 37 fractions). Pelvic lymph nodes were included in the treatment volume and treated to a median dose of 45 Gy in 25 fractions for 283 cases (40%). The primary end-point was biochemical relapse-free survival from RT using the American Society of Therapeutic Radiology and Oncology (ASTRO) consensus criteria. Favourable, intermediate and unfavourable pre- treatment prognostic groupings were derived from the initial PSA, T-category, and Gleason score using Cox regression analysis. Secondary end-points included survival, metastases-free survival and clinical local control. RESULTS: The overall biochemical relapse-free rate at 2 and 5 years was 63% and 45% respectively. Overall survival at 5 years was 87%, and metastases-free survival was 86%. Local control by DRE was 72% at 5 years. Multivariate analysis of variables associated with time to biochemical failure after RT showed that pre-RT PSA, T-category and Gleason score were significant independent predictors with hazard ratios of 1.33 (P = 0.0001), 1.22 (P = 0.01) and 1.33 (P = 0.029) respectively. PSA nadir was an early indicator of biochemical failure. The biochemical failure rate at 3 years was 20% for a PSA nadir < or = 0.5 ng/ml and 85% for a PSA nadir > or = 2.0 ng/ml (P < 0.0001). CONCLUSION: The results of conventional dose RT were unsatisfactory for all risk categories, and overall, less than half of the treated patients remained in biochemical remission at 5 years. These men require more aggressive therapy, that may include dose escalation with conformal techniques, and neoadjuvant/adjuvant androgen deprivation therapy. These results highlight the need to support new and on-going clinical trials for management of localized disease.
OBJECTIVE: To evaluate practice patterns of the management of stage I seminoma of testis in Canada and a selected group in the United States. MATERIALS AND METHODS: Survey among radiation oncologists treating genitourinary (GU) tumors in Canada and the RTOG GU committee members in the United States between January and March 2001. RESULTS: Response rate was 78% (73/93) in Canada and 67% (24/36) in the United States. Eighty-four percent described their clinical practice as a university affiliated teaching center, and 16% as community-based or private practice. Sixty-two percent, 31% and 7% would manage 1-5, 6-10 and > oe = 11 cases per year respectively. Almost all would perform chest x-ray (99%) and CT scan of abdomen and pelvis (100%) as staging investigation following radical inguinal orchiectomy. Forty percent also arranged CT scan of chest, while only 18% routinely obtained lymphangiogram. Seventy-eight percent offered surveillance as a management option and estimated that 20% (median) of patients would choose surveillance in their practice. Among four management options: (1. surveillance, 2. radiotherapy (RT) to the para-aortic region, 3. RT to the para-aortic and ipsilateral pelvis ('dog-leg'), 4. single-agent chemotherapy), the order of first preference was option 1 (44%), 2 (42%), and 3 (14%) for patients who wish to preserve fertility. When fertility was not a major concern, it was option 2 (43%), 3 (39%), and 1 (17%). The commonest dose-fractionation schedule was 25 Gy/20 fractions (68%). Others included 25 Gy/15 f (15%), and 25.5 Gy/17 f (4%). Forty-five percent chose the para-aortic region, while 53% used the 'dog-leg' as RT volume. Twenty-nine percent reduced RT volume from the 'dog-leg' to the para-aortic region as the result of MRC Phase III study published in 1999. CONCLUSION: There are significant variations in the practice pattern of the management of stage I seminoma of testis among radiation oncologists in Canada and a selected group in the United States.
Treatment options in patients with stage I testicular seminoma include adjuvant radiotherapy (RT), surveillance, and adjuvant chemotherapy. RT was the treatment of choice for the past 50 years, but there has been increasing concern in the past decade regarding late complications. Surveillance, reserving treatment for patients who relapse, has been shown to be a safe and effective strategy. It allows >80% of patients to avoid any post-orchidectomy treatment and is the recommended approach for these patients. The possible role of adjuvant chemotherapy is currently being assessed in clinical trials and should not be used outside of a study setting.
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