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D P Dearnaley

Publications and source records attributed to D P Dearnaley.

At least 73 records · Page 4Linked to original sources
PubMed1999

A comparison of coplanar four-field techniques for conformal radiotherapy of the prostate.

BACKGROUND AND PURPOSE: Conformal radiotherapy of the prostate is an increasingly common technique, but the optimal choice of beam configuration remains unclear. This study systematically compares a number of coplanar treatment plans for four-field irradiation of two different clinical treatment volumes: prostate only (PO) and the prostate plus seminal vesicles (PSV). MATERIALS AND METHODS: A variety of four-field coplanar treatment plans were created for PO and PSV volumes in each of ten patients. Plans included a four-field 'box' plan, a symmetric plan having bilateral anterior and posterior oblique fields, a plan with anterior oblique and lateral fields, a series of asymmetric plans, and a three-field plan having anterior and bilateral fields for comparison. Doses of 64 and 74 Gy were prescribed to the isocentre. Plans were compared using the volume of rectum irradiated to greater than 50% (V50), 80% (V80) and 90% (V90) of the prescribed dose. Tumour control probabilities (TCP) and normal tissue complication probabilities (NTCP) for the rectum, bladder and femoral heads were also evaluated. Femoral head dose was limited such that less than 10% of each femoral head received 70% of the prescribed dose. RESULTS: For the PO group, the optimal plan consisted of anterior oblique and lateral fields (Rectal V80 = 23.8+/-5.0% (1 SD)), while the box technique (V80 = 26.0+/-5.8%) was less advantageous in terms of rectal sparing (P = 0.001). Similar results were obtained for the PSV group (Rectal V80 = 43.9+/-5.0% and 47.3+/-5.5% for the two plan types, respectively, P = 0.001). The three-field plan was comparable to the optimal four-field plan but gave higher superficial body dose. With dose escalation from 64 to 74 Gy, the mean TCP for the optimal plan rose from 52.0+/-2.8% to 74.1+/-2.0%. Meanwhile, rectal NTCP for the optimal plan rose by 3.5% (PO) or 8.4% (PSV), compared to 4.7% (PO) or 10.1% (PSV) for the box plan. CONCLUSIONS: For PO volumes, a plan with gantry angles of 35 degrees, 90 degrees, 270 degrees and 325 degrees offers a high level of rectal sparing and acceptable dose to the femoral heads for all patients, while for PSV volumes, the corresponding plan has gantry angles of 20 degrees, 90 degrees , 270 degrees and 340 degrees. Using these plans, the gain in TCP resulting from dose escalation can be achieved with a smaller increase in anticipated rectal NTCP.

Algorithms↗
PubMed1999

Bone marrow doses and leukaemia risk in radiotherapy of prostate cancer.

BACKGROUND AND PURPOSE: As more and more patients with prostate cancer are cured and survive with only minor chronic morbidity, other potentially treatment related morbidity, in particular second cancers, becomes an urgent problem which may influence decisions on treatment strategy and treatment plan optimisation. Epidemiological data suggest a radiotherapy associated risk of AML in prostate cancer patients of approximately 0.1% in 10 years. The aim of the study was to determine the range of bone marrow doses from different treatment plans and in different patients in order to develop criteria for optimisation of treatment plans in conformal radiotherapy of prostate cancer to further minimise the small risk of secondary leukaemia. MATERIALS AND METHODS: Doses to the pelvic bone marrow were calculated for eight different plans used in radiotherapy of prostate cancer to determine the variability of bone marrow doses in radiotherapy of prostate cancer. Computer tomography (CT) slices of the entire pelvic region of an Alderson phantom were acquired and transferred to the TPS. Critical bone marrow structures were outlined in each slice. Different treatment plans were evaluated on this phantom and dose-volume histograms (DVH) for the pelvic bone marrow were obtained. Similarly, the DVH for the bone marrow of 14 patients who received conformal radiotherapy for prostate cancer was determined. RESULTS: Mean total bone marrow doses ranged from 3.4 to 5.6 Gy in the phantom study. Approximately 99% of the mean dose to the total bone marrow comes from the dose to bone marrow located in the pelvic bones and lumbar vertebrae. Mean bone marrow doses of 14 patients given the same conformal radiotherapy plan ranged from 3.5 to 7.7 Gy. CONCLUSIONS: No correlation was found between the rectum normal tissue complication probability (NTCP) and the mean bone marrow dose. This means that in the process of treatment planning, exposure to both critical organs, the rectum as well as the bone marrow, should be minimised independently to arrive at the optimal treatment plan.

Bone Marrow↗
PubMed1999

Improved methods for adding transaxial two-dimensional margins to the superior and inferior regions of a clinical target volume.

When adding laminar or 2-D margins to the clinical target volume (CTV), additional borders are required superiorly and inferiorly. Two common strategies for adding these margins, the cylindrical method (CYL) and the chamfer method (CHR), are discussed, and improved 2-D methods are presented. The improved cylindrical method (ICYL) extends the PTV superiorly and inferiorly, but the uppermost and lowermost PTV outlines are limited laterally to the extent of the CTV. If the required 3-D margin is M, the improved chamfer method (ICHR) constructs a transaxial margin of the square root of M2-d2 on a CT plane which is a distance d above the most superior CTV outline. For a theoretical tumor, CYL and CHR overestimate and underestimate the superior target margin by 8.1 cm3 and 9.6 cm3, respectively, whereas ICYL overestimates by only 2.2 cm3 and ICHR provides the desired margin. For eight esophageal tumors (specified margin 20 mm), CHR systematically underestimates the margin on the slice immediately inferior to the CTV by 7 mm (median, range 7-27 mm, p<0.01), while CYL overestimates the margin two slices inferior to the CTV by 20 mm in all cases. ICYL removes the overestimation of CYL, but retains an overestimation of 3 (-17-3) mm (p<0.01) on the first slice inferior to the CTV. ICHR performs most accurately, the margin width being equal to that of a true 3-D margin, except for occasional underestimations (0-33 mm, p<0.01). Similar results are demonstrated for eight prostatic tumors (specified margin 10 or 15 mm), but with the more irregular tumor shape causing all 2-D methods to underestimate the margin, most notably by 4.5 (0-21) mm (p<0.01) on the inferior CTV slice for a 15-mm margin. In general, both improved 2-D methods produce significantly more accurate margins than the conventional methods, the margin produced by the improved chamfer method most closely approximating a true 3-D margin.

Esophageal Neoplasms↗
PubMed1999

Lymph node staging in clinically localized prostate cancer.

Pelvic lymph node involvement is an adverse prognostic factor in clinically localized prostate cancer, and a knowledge of nodal status is important for patient management. Whereas nodal disease has been widely regarded as incurable, evidence is now accumulating that some men with lymph node involvement may benefit from radical multimodality treatment approaches. Pelvic nodal status may be assessed by predictive nomograms, by imaging studies and by surgery. The pros and cons of each method are discussed together with the prospects for future development. Optimal strategies combining the different diagnostic approaches for the detection of lymph node metastases are considered in the context of the changing therapeutic implications of nodal disease.

Journal Article↗
PubMed1999

Hypofractionated radiotherapy for patients with carcinoma of the bladder.

In order to develop a low toxicity regimen of bladder radiotherapy for the palliation of patients with poor performance status we carried out a Phase II study of weekly 6 Gy fractions to a maximum dose of 30-36 Gy in 65 patients with T(2)-T(4) bladder cancer (median age 81 years). A complete response was obtained in 23/37 (62%) assessable patients at cystoscopy. Local control was achieved in 16/65 (25%) patients. The median survival of all 65 patients was 35 weeks, and the 2-year actuarial survival 21%. The main acute toxicity was urinary frequency as often as hourly at the peak of the reaction (Radiation Therapy Oncology Group (RTOG) grade 3) in seven patients, and urinary obstruction (RTOG grade 4) in one. The reactions may have been compounded by the effects of locally advanced tumour. Late bladder toxicity amongst the 16 patients who were evaluable after 1 year included four patients with persisting frequency, one with severe haematuria (RTOG grade), and one with a bladder capacity <100 ml (RTOG grade 4). One patient experienced RTOG grade 4 late bowel and bladder morbidity. Weekly 6 Gy fractions to a total dose of 30-36 Gy is a satisfactory palliative regimen for patients with advanced bladder cancer who cannot tolerate standard radical radiotherapy, but it may produce significant late bladder morbidity.

Aged↗
PubMed1999

Comparison of MRI with CT for the radiotherapy planning of prostate cancer: a feasibility study.

This feasibility study was performed to evaluate the suitability of MRI in defining appropriate pelvic radiotherapy treatment volumes, and to compare MRI sequences with CT for prostate cancer radiotherapy. Five patients with localized prostate cancer, imaged with four MRI sequences (spin echo (SE) T1, turbo SE (TSE) T2, high resolution TSE (HR) T2, and FLASH 3D (F3D)), compared with their corresponding CT planning scans. Segmentation ability of the following pelvic structures: prostatic apex (PA), prostate, rectum, bladder and seminal vesicles (SV), were evaluated by three independent observers. They used a five point grading scale based on the anatomical definition of the organ boundary, tissue contrast and multiplanar display. Results were averaged for the group and for each sequence. There was no significant interobserver variation in the assessed scores (p > 0.1). The average scores (+/- 1 SD) for all pelvic structures assessed by each imaging sequence were CT 1.3 +/- 0.6; SE T1 2.4 +/- 0.9; TSE T2 2.4 +/- 0.7; HR T2 2.2 +/- 0.7 and F3D 3.4 +/- 0.6. Compared with CT, the average MR score for each assessed pelvic structure was higher with a trend for all transaxial MR sequences to provide improved segmentation of the PA and rectum. The F3D sequence scored highest as it provided multiplanar views and avoided the problem of partial volume averaging. MRI, compared with CT, appears to provide improved definition of pelvic treatment volumes but further work is required to confirm this and to address the issues of MRI associated distortion and dosimetry before MRI can be used routinely for pelvic radiotherapy planning.

Aged↗
PubMed1998

Comparison of 2D and 3D algorithms for adding a margin to the gross tumor volume in the conformal radiotherapy planning of prostate cancer.

PURPOSE: To evaluate the adequacy of tumor volume coverage using a three-dimensional (3D) margin-growing algorithm compared to a two-dimensional (2D) margin-growing algorithm in the conformal radiotherapy planning of prostate cancer. METHODS AND MATERIALS: Two gross tumor volumes (GTV) were segmented in each of 10 patients with localized prostate cancer; prostate gland only (PO) and prostate with seminal vesicles (PSV). A predetermined margin of 10 mm was applied to these two groups (PO and PSV) using both 2D and 3D margin-growing algorithms. The 2D algorithm added a transaxial margin to each GTV slice, whereas the 3D algorithm added a volumetric margin all around the GTV. The true planning target volume (PTV) was defined as the region delineated by the 3D algorithm. The adequacy of geometric coverage of the GTV by the two algorithms was examined in a series of transaxial planes throughout the target volume. RESULTS: The 2D margin-growing algorithm underestimated the PTV by 17% (range 12-20) in the PO group and by 20% (range 13-28) for the PSV group when compared to the 3D-margin algorithm. For the PO group, the mean transaxial difference between the 2D and 3D algorithm was 3.8 mm inferiorly (range 0-20), 1.8 mm centrally (range 0-9), and 4.4 mm superiorly (range 0-22). Considering all of these regions, the mean discrepancy anteriorly was 5.1 mm (range 0-22), posteriorly 2.2 (range 0-20), right border 2.8 mm (range 0-14), and left border 3.1 mm (range 0-12). For the PSV group, the mean discrepancy in the inferior region was 3.8 mm (range 0-20), central region of the prostate was 1.8 mm ( range 0-9), the junction region of the prostate and the seminal vesicles was 5.5 mm (range 0-30), and the superior region of the seminal vesicles was 4.2 mm (range 0-55). When the different borders were considered in the PSV group, the mean discrepancies for the anterior, posterior, right, and left borders were 6.4 mm (range 0-55), 2.5 mm (range 0-20), 2.6 mm (range 0-14), and 3.9 mm (range 0-45), respectively. Underestimation of the required margin with the 2D algorithm occurred when the transaxial definition of the GTV shifted in position significantly between successive adjacent slices, resulting in transaxial discrepancies of up to 22 mm and 55 mm, respectively, for the PO and PSV groups. In the superior regions, the 2D algorithm was inadequate, often providing a margin of less than 3 mm compared to the 10 mm margin delineated by the 3D algorithm. CONCLUSION: This study illustrates that target margins added by a laminar method in the transaxial plane are inadequate for covering a 3D tumor volume so that a margin-growing algorithm which fully takes into account the 3D shape of the GTV should be used. If a 2D-margin method is utilized, an appreciation of spatial margins in 3D is required.

Aged↗
PubMed1998

Immunohistochemical expression of BRCA2 protein and allelic loss at the BRCA2 locus in prostate cancer. CRC/BPG UK Familial Prostate Cancer Study Collaborators.

Many epidemiological studies have reported an association between breast and prostate cancer. BRCA2 functions as a tumour-suppressor gene in about 35% of large familial breast-cancer clusters; its role in the pathogenesis of sporadic breast cancer is less clear. We have evaluated immunohistochemical expression of BRCA2 protein and allelic loss of markers at the BRCA2 locus in tissue derived both from sporadic and from familial cases of prostate cancer. Immunohistochemical analysis was performed in 167 paraffin-embedded archival specimens. Normal prostate and 75% (120/160) of prostate-cancer tissue did not express BRCA2 protein. However, 25% (40/160) of cancer cases did express patchy staining; of these, 17% (2711 60) expressed positive nuclear staining in normal glandular tissue adjacent to tumour (either in addition to, or, independent of tumour). Allelic loss is the hallmark of a tumour-suppressor gene. Markers flanking (D13S267, D13S260) and within (D13S171) the BRCA2 gene indicated allelic loss in at least one locus in 23% (17/73) of tumours analyzed. There was no difference in the rates of allelic loss between sporadic and familial tumours, nor was there any association between immunohistochemical staining and allelic loss. Although immunohistochemical staining provided no useful prognostic information, allelic loss at BRCA2 was shown in univariate analysis to be associated with poorer survival (log-rank test, p = 0.046).

BRCA2 Protein↗
PubMed1998

Portal imaging protocol for radical dose-escalated radiotherapy treatment of prostate cancer.

PURPOSE: The use of escalated radiation doses to improve local control in conformal radiotherapy of prostatic cancer is becoming the focus of many centers. There are, however, increased side effects associated with increased radiotherapy doses that are believed to be dependent on the volume of normal tissue irradiated. For this reason, accurate patient positioning, CT planning with 3D reconstruction of volumes of interest, clear definition of treatment margins and verification of treatment fields are necessary components of the quality control for these procedures. In this study electronic portal images are used to (a) evaluate the magnitude and effect of the setup errors encountered in patient positioning techniques, and (b) verify the multileaf collimator (MLC) field patterns for each of the treatment fields. METHODS AND MATERIALS: The Phase I volume, with a planning target volume (PTV) composed of the gross tumour volume (GTV) plus a 1.5 cm margin is treated conformally with a three-field plan (usually an anterior field and two lateral or oblique fields). A Phase II, with no margin around the GTV, is treated using two lateral and four oblique fields. Portal images are acquired and compared to digitally reconstructed radiographs (DRR) and/or simulator films during Phase I to assess the systematic (CT planning or simulator to treatment error) and the daily random errors. The match results from these images are used to correct for the systematic errors, if necessary, and to monitor the time trends and effectiveness of patient imobilization systems used during the Phase I treatment course. For the Phase II, portal images of an anterior and lateral field (larger than the treatment fields) matched to DRRs (or simulator images) are used to verify the isocenter position 1 week before start of Phase II. The Portal images are acquired for all the treatment fields on the first day to verify the MLC field patterns and archived for records. The final distribution of the setup errors was used to calculate modified dose-volume histograms (DVHs). This procedure was carried out on 36 prostate cancer patients, 12 with vacuum-molded (VacFix) bags for immobilization and 24 with no immobilization. RESULTS: The systematic errors can be visualized and corrected for before the doses are increased above the conventional levels. The requirement for correction of these errors (e.g., 2.5 mm AP shift) was demonstrated, using DVHs, in the observed 10% increase in rectal volume receiving at least 60 Gy. The random (daily) errors observed showed the need for patient fixation devices when treating with reduced margins. The percentage of fields with displacements of < or = 5.0 mm increased from 82 to 96% with the use of VacFix bags. The rotation of the pelvis is also minimized when the bags are used, with over 95% of the fields with rotations of < or = 2.0 degrees compared to 85% without. Currently, a combination of VacFix and thermoplastic casts is being investigated. CONCLUSION: The systematic errors can easily be identified and corrected for in the early stages of the Phase I treatment course. The time trends observed during the course of Phase I in conjunction with the isocenter verification at the start of Phase II give good prediction of the accuracy of the setup during Phase II, where visibility of identifiable structures is reduced in the small fields. The acquisition and inspection of the portal images for the small Phase I fields has been found to be an effective way of keeping a record of the MLC field patterns used. Incorporation of the distribution of the setup errors into the planning system also gives a clearer picture of how the prescribed dose was delivered. This information can be useful in dose-escalation studies in determining the relationship between the local control or morbidity rates and prescribed dose.

Humans↗
PubMed1998

The management of PSA failure after radical radiotherapy for localized prostate cancer.

An asymptomatic rising serum prostate-specific antigen (PSA) level is the most common form of failure after radical radiotherapy for localized prostate cancer, but there is no consensus as to how it should be managed. This review addresses the following three questions concerning men with PSA failure after radiotherapy: (i) what is the course of the disease without further intervention?; (ii) what is the role of radical treatment, such as salvage prostatectomy?; and (iii) should androgen deprivation be started immediately or should it be delayed until clinical progression occurs? An algorithm for the management of PSA failure after radical radiotherapy for localized prostate cancer is proposed.

Aged↗
PubMed1998

Allelic imbalance in familial and sporadic prostate cancer at the putative human prostate cancer susceptibility locus, HPC1. CRC/BPG UK Familial Prostate Cancer Study Collaborators. Cancer Research Campaign/British Prostate Group.

A recent report has provided strong evidence for a major prostate cancer susceptibility locus (HPC1) on chromosome 1q24-25 (Smith et al, 1996). Most inherited cancer susceptibility genes function as tumour-suppressor genes (TSGs). Allelic loss or imbalance in tumour tissue is often the hallmark of a TSG. Studies of allelic loss have not previously implicated the chromosomal region 1q24-25 in prostate cancer. However, analysis of tumour DNA from cases in prostate cancer families has not been reported. In this study, we have evaluated DNA from tissue obtained from small families [3-5 affected members (n = 17)], sibling pairs (n = 15) and sporadic (n = 40) prostate tumours using the three markers from Smith et al (1996) that defined the maximum multipoint linkage lod score. Although widely spaced (12-50 cM), each marker showed evidence of allelic imbalance in only approximately 7.5% of informative tumours. There was no difference between the familial and sporadic cases. We conclude that the incidence of allelic imbalance at HPC1 is low in both sporadic tumours and small prostate cancer families. In this group of patients, HPC1 is unlikely to be acting as a TSG in the development of prostate cancer.

Aged↗
PubMed1998

A pilot study of intermittent androgen deprivation in advanced prostate cancer.

OBJECTIVE: To assess the feasibility of intermittent hormone therapy for metastatic prostate cancer. PATIENTS AND METHODS: Sixteen patients with metastatic carcinoma of the prostate were treated using a protocol of intermittent hormone therapy with the luteinizing hormone-releasing hormone (LHRH) analogue leuprorelin at a dose of 3.75 mg every 4 weeks. The protocol required that hormone therapy be stopped when the response was stable, and was designed to assess the duration of the unmaintained response and the probability of a second response to re-initiation of leuprorelin. RESULTS: Eleven of the 16 patients had a stable hormone response and stopped therapy 3-9 months (mean 5.5) from the start of treatment. The mean (range) duration of the unmaintained response, as judged by monitoring symptoms and serum prostate specific antigen (PSA) levels every month was 4 (2-8) months in the seven patients who had bone metastases and was 3, 3 and 6 months in the three with only loco-regional disease (one patient temporarily discontinued follow-up). As the immediate re-induction of hormone therapy was not mandatory in asymptomatic patients at the time of progression, the mean (range) period off hormone therapy was 8 (3-13) months in those eight patients with bone metastases and was 3, 36 and 42 + months in the three presenting with loco-regional disease. All 10 patients who re-initiated hormone therapy had a second hormone response, in six of which led to a decline in PSA level to < 2 ng/mL. During the period off hormone therapy no patient developed irreversible symptoms. CONCLUSIONS: The temporary cessation of hormone therapy early during the response in patients with metastatic carcinoma of prostate is associated with biochemical evidence of relatively early progression in most cases, but can be associated with significant periods off therapy and with a high chance of a second hormone response. The value of this approach to the quality and duration of patients' lives requires a prospective comparative evaluation.

Androgen Antagonists↗
PubMed1997

[Basic principles and initial results of adjuvant hormone therapy and irradiation of prostatic carcinoma].

Radiotherapy is an effective treatment for localized prostate cancer. A dose response relationship has been demonstrated for both local tumor control and complications. Reducing the volume of normal tissue treated may allow dose escalation without an increase in RT induced side effects. Androgen blockade before RT could, by reducing tumor volume, increase local control, disease-free (DFS) and overall survival in patients (pts) with prostatic adenocarcinoma. A total of 79 patients with T2-T4 prostate cancer have been treated initially with LHRH agonists and cyproterone acetate followed by radical irradiation between 1988 and 1993. The first cohort of 22 patients were monitored intensively by transrectal ultrasound and computed tomography. For each patient conformal photon beam radiotherapy and conventional treatment plans were produced and dose volume histograms compared for total volume, rectal volume, and bladder volume. Overall mean reduction of prostate volume was about 50%, and radiotherapy target volume was reduced by 37%. 53 further patients without clinical evidence of regional or distant metastases were given 3 months preradiotherapeutic hormonal cytoreduction with a short course of cyproterone acetate and LHRH. PSA level fell rapidly in most patients and after 3 months treatment the median PSA level was 1 ng/ml and 83% had PSA level 10 ng/ml. At 18 months PSA levels continued to be < 2 ng/ml in 70% of the patients. Combined modality treatment with the neoadjuvant or adjuvant androgen deprivation and conformal therapy show considerable promise as novel methods to improve the therapeutic ratio. This treatment approach may be used to explore the possibility of dose escalation in prostate cancer to enhance local control, and therapeutic randomised studies are underway to test these approaches.

Adenocarcinoma↗
PubMed1997

Magnetic resonance imaging (MRI): considerations and applications in radiotherapy treatment planning.

The emerging utilisation of conformal radiotherapy (RT) planning requires sophisticated imaging modalities. Magnetic resonance imaging (MRI) has introduced several added imaging benefits that may confer an advantage over the use of computed tomography (CT) in RT planning such as improved soft tissue definition, unrestricted multiplannar and volumetric imaging as well as physiological and biochemical information with magnetic resonance (MR) angiography and spectroscopy. However, MRI has not yet seriously challenged CT for RT planning in most sites. The reasons for this include: (1) the poor imaging of bone and the lack of electron density information from MRI required for dosimetry calculations; (2) the presence of intrinsic system-related and object-induced MR image distortions; (3) the paucity of widely available computer software to accurately and reliably integrate and manipulate MR images within existing RT planning systems. In this review, the basic principals of MRI with its present potential and limitations for RT planning as well as possible solutions will be examined. Methods of MRI data acquisition and processing including image segmentation and registration to allow its application in RT planning will be discussed. Despite the difficulties listed, MRI has complemented CT-based RT planning and in some regions of the body especially the brain, it has been used alone with some success. Recent work with doped gel compounds allow the MRI mapping of dose distributions thus potentially providing a quality assurance tool and in a manner analogous to CT, the production of dose-response information in the form of dose volume histograms. However, despite the promise of MRI, much development research remains before its full potential and cost-effectiveness can be assessed.

Abdominal Neoplasms↗
PubMed1997

Acute toxicity in pelvic radiotherapy; a randomised trial of conformal versus conventional treatment.

BACKGROUND: A prospective, randomized clinical trial to assess the effect of reducing the volume of irradiated normal tissue on acute reactions in pelvic radiotherapy accured 266 evaluable patients between 1988 and 1993. PURPOSE: This is the definitive analysis to assess the differences between the conformal and conventional arms of the trial. MATERIALS AND METHODS: In both arms, patients were treated with 6 MV X-rays using a 3-field technique (in all but 5 cases) consisting of an anterior and two wedged lateral or posterior oblique fields; in the conventional arm, rectangular fields were employed, whereas in the conformal arm, the fields were shaped with customized blocks drawn according to the beam's-eye-view of the target volume. The most common dosage was 64 Gy in 2-Gy fractions 5 times a week, although a subgroup (of ca. bladder patients) were treated with 30-36 Gy in once-a-week 6 Gy fractions. Each patients completed a comprehensive acute toxicity scoring questionnaire concentrating on bowel and bladder problems, tiredness and nausea, before the start of treatment, weekly during and for 3 weeks after the end of treatment and then monthly for a further 2 months. compliance was excellent. RESULTS: There were no differences between the patients in the two arms with respect to age, gender, tumour type (52% prostate, 41% bladder, 5% rectum, 2% other) fractionation/dosage, anterior field size, weight, or baseline symptoms. Substantial differences in normal-tissue volumes (rectum, bladder, etc.) were achieved: median high-dose volume (HDV) of 689 cm3 for the conformal technique versus 792 cm3 for the conventional. A clear pattern of an increase in symptoms during RT, followed by a decrease after RT, was observed for the patient group as a whole. However, a very extensive analysis has not revealed any (statistically) significant differences between the two arms in level of symptoms, nor in medication prescribed. The disparity between our findings and those of other, non-randomized studies is discussed. CONCLUSIONS: The data on late effects must be collected and analyzed before any definite conclusions can be drawn on the benefits of conformal therapy in the pelvis.

Aged↗
PubMed1997

Spinal cord compression in prostate cancer: treatment outcome and prognostic factors.

BACKGROUND AND PURPOSE: Spinal cord compression (SCC) is an important complication of metastatic prostate cancer. We have analysed patients treated at the Royal Marsden Hospital to assess treatment outcome and prognostic factors in this patients group. MATERIALS AND METHODS: We performed retrospective analysis of 69 patients with spinal cord compression and prostate cancer treated at the Royal Marsden Hospital. RESULTS: At presentation 40 (58%) patients were non-ambulant and 52% were catheterised. Diagnosis was established by myelography in 42% and magnetic resonance imaging (MRI) in 47% of patients. MRI detected significantly more patients with multiple sites of compression (51 versus 7%, P < 0.001). SCC was present at the initial diagnosis of prostatic cancer in 13 patients and 17 patients had received no hormone treatment prior to diagnosis. Following treatment 36 (52%) patients had a functional improvement of motor power with 25/40 (63%) non-ambulant patients becoming ambulant. Seventy-seven percent of patients who had eventual improvement had some improvement in power within 7 days. On multivariate analysis a single level of compression, no previous hormone therapy and a young age (<65 years) predicted for better outcome. When these factors were included an increased radiation dose (>30 Gy) or the addition of surgery did not improve the functional outcome. Following initial recovery; there was a 45% risk of developing a further episode of cord compression at the same or new site by 2 years with a median time to progression of 236 days (range 47-1215 days). The median survival was 115 days (range 5-2016 days) with 25% of patients surviving for 2 years. Patients with no prior hormone therapy had a median survival of 627 days (range 46-1516 days). Other predictors of improved survival on multivariate analysis were a single site of compression and a haemoglobin over 12 g. CONCLUSIONS: Treatment of SCC in prostate cancer results in improved motor function in the majority of patients. Long-term survival is possible, especially in good performance status patients with no prior hormone treatment. Survivors remain at high risk of subsequent neurological relapse. An early improvement in motor power is a strong predictor of subsequent functional improvement. MRI detects additional sites of asymptomatic SCC which makes it the investigation of choice.

Aged↗