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Biomedical subjects

A Kramar

Publications and source records attributed to A Kramar.

At least 19 recordsLinked to original sources

Phase II study of all-trans retinoic acid administered intermittently for hormone refractory prostate cancer.

PURPOSE: We assess the efficacy and toxicity of all-trans retinoic acid administered intermittently for hormone refractory prostate cancer. MATERIALS AND METHODS: A total of 26 patients with histologically confirmed adenocarcinoma of the prostate and manifestations of progressive metastatic disease, despite at least 1 hormonal therapy, were included in the study. Patients received a single oral dose of 45 mg./m.2 all-trans retinoic acid daily for 7 days followed by 7 days of no treatment, and then resumed treatment on day 14. This schedule was continued until progression or limiting toxicity occurred. Response was assessed based on serial measurements of serum prostate specific antigen and pain scores every other week. In addition, objective responses were evaluated every 12 weeks in patients with bi-dimensionally measurable metastases. RESULTS: All-trans retinoic acid was administered for 168 weeks (median 6 weeks per patient, range 2 to 21). Toxicity was mild. No patient stopped therapy because of toxicity. Of the patients 4 (15%) demonstrated a biological response of 50% or greater serum prostate specific antigen decrease. No objective response was observed among 11 patients with measurable metastases. Of 17 patients who required analgesics at the onset of all-trans retinoic acid treatment only 1 achieved a significant reduction of pain. Median survival time from the onset of all-trans retinoic acid treatment was 19 months (range 2 to 24). CONCLUSIONS: All-trans retinoic acid has minimal activity in hormone refractory prostate cancer.

Adenocarcinoma

Prognostic factors for survival in patients with brain metastases from renal cell carcinoma.

BACKGROUND: Patients presenting with brain metastases from renal cell carcinoma portend a poor prognosis, with a reported median survival of 4-6 months. Given their short life expectancy, these patients generally have been excluded from clinical trials that assess the efficacy of medical treatments. However, clinical impression suggests that some patients may achieve long term palliation. METHODS: The clinical features of 68 patients who were treated at the Institut Gustave Roussy for brain metastases from renal cell carcinoma were collected retrospectively. Using univariate and multivariate analyses, a prognostic model based on independent prognostic factors was established. An external data set of 57 patients was used to validate the model. RESULTS: The median survival was 7 months. On univariate analysis survival was related significantly to the following adverse prognostic factors: no initial nephrectomy, left side and temporal location of brain metastases, presence of fever or weight loss, erythrocyte sedimentation rate > 50 mm/h, and time from initial diagnosis to brain metastases < or = 18 months. Multivariate analyses identified the previous variable as well as the presence of other visceral metastases as independent prognostic factors. Forty-four patients (65%) with no or 1 adverse prognostic factor (average risk group) had a median survival of 8 months and a 26% 1-year survival rate. Twenty-four patients (35%) with 2 adverse prognostic factors (poor risk group) had a median survival of 3 months and a 1-year survival rate of 9%. This model proved to be discriminant in an external data set; the median survival of patients assigned to the average risk group was 11 months (46% 1-year survival rate) compared with 4 months (9% 1-year survival rate) for patients assigned to the poor risk group. CONCLUSIONS: Patients presenting with brain metastases from renal cell carcinoma and poor risk prognostic factors are highly unlikely to benefit from medical treatments except symptomatic procedures. Conversely, the enrollment of patients with average risk prognostic factors into clinical trials dealing with chemotherapy or immunotherapy may be considered.

Adolescent

Tumour size in cancer of the cervix.

In a randomized trial comprising 204 patients with operable cervical carcinomas stages I and II, two low-dose rates in gynaecological brachytherapy were compared. Treatment consisted of Cs-137 uterovaginal application followed by surgery (either immediate or delayed). The results for the two dose rates have been published previously. The present paper concerns the correlation between outcome and tumour size. Tumour size was carefully estimated in two ways: by clinical examination under general anaesthesia and by measurements on the customized vaginal mould used for the brachytherapy. Ninety-one patients (45%) were classified as stage I, and 113 were classified as stage II proximal. The mean tumour size was 39 mm (range 15-64 mm). Cox's multivariate analysis indicated that the factors with a poor prognostic value were for survival: node involvement (N +) (p < 0.001), large tumour size (T +) (p < 0.001) and involvement of the endocervix (E +) (p <0.01); for event-free survival: N + (p <0.001), T + (p < 0.001); for local control; N + (p = 0.0001); for metastasis and regional relapse: N + (p < 0.001) and T + (p < 0.001). Stage was not a prognostic factor over the present range in either univariate or multivariate analysis. In this series tumour size is a powerful independent prognostic factor. It is therefore suggested that for the classification of cervical cancer and the indications for surgical staging and adjuvant treatment, tumour size should be taken into account.

Adult

Primary mediastinal nonseminomatous germ cell tumors: results of modern therapy including cisplatin-based chemotherapy.

PURPOSE: Primary mediastinal nonseminomatous germ cell tumors (NSGCT) are uncommon neoplasms and clinically and biologically distinct from other germ cell tumors (GCT). We describe the clinical and biologic features of these patients and evaluate the results of treatment during the cisplatin era. PATIENTS AND METHODS: Between 1976 and 1993, 38 patients with mediastinal NSGCT received cisplatin-based chemotherapy as part of their primary treatment. Twenty-nine of them were initially treated at the Institut Gustave-Roussy (IGR), VillejuiF, France, and nine were referred for salvage treatment. RESULTS: Of the 29 patients initially treated at IGR, 11 (39%) had metastasis. A complete response (CR) to therapy was obtained in 19 of 29 patients (66%) after chemotherapy and surgery. Ten patients (34.5%) have remained free of disease with a median follow-up of 89 months. All patients who did not achieve a CR died of disease. The 2-year overall survival rate for the IGR patients is 45% and the 2-year disease-free survival is 37%. Only the presence of extrapulmonary metastasis was of prognostic significance in the univariate analysis (P = .0095). None of the 20 patients who required salvage therapy is currently disease-free. Five patients developed and subsequently died of a hematologic malignancy at an interval range of 1 to 47 months from treatment of mediastinal NSGCT. Cytogenetic analysis of leukemic cells found an isochromosome of the short arm of chromosome 12 (12p) in two cases. The incidence of leukemia was 21% in patients who attained a CR. CONCLUSION: Primary mediastinal NSGCT is a clinical and biologic entity that should be distinguished from other GCT. About 40% of these patients can envisage long-term survival with modern therapy that includes cisplatin-based chemotherapy followed by surgical resection of residual masses. New strategies are required for patients who do not attain a CR. Predictive factors and improvement in therapy are required for mediastinal NSGCT-associated leukemia.

Adolescent

Four-step high-dose sequential chemotherapy with hematopoietic progenitor-cell support as induction treatment for patients with solid tumors.

BACKGROUND: Despite recent progress in modern chemotherapy, metastatic solid tumors still have a poor outcome. The delivery of increased dose intensities of cytotoxic agents could improve response rates. We assessed the feasibility and safety of a high-dose sequential chemotherapy program in chemotherapy-naive patients with solid tumors. PATIENTS AND METHODS: Thirty patients (14 with carcinoma of unknown primary site, seven with metastatic breast cancer, six with small-cell lung cancer, and three with other diseases) were treated by an induction therapy regimen consisting of four cycles of high-dose chemotherapy with hematopoietic progenitor cell and growth factor support. Peripheral blood progenitor cells were collected by apheresis as the leukocyte counts recovered from the nadir induced by the first cycle of chemotherapy (doxorubicin 75 mg/m2, cyclophosphamide 6000 mg/m2). Patients then received two cycles of etoposide (800 mg/m2) and carboplatin (900 mg/m2) separated by one cycle of doxorubicin (75 mg/m2) and cyclophosphamide (3000 mg/m2). G-CSF (5 microg/kg/d) was given until engraftment. Cycles were scheduled to be delivered every three weeks. RESULTS: A total of 108 cycles of chemotherapy were administered. Six patients went off study before the end of the program (three because of progressive disease, three because of toxicity). After the first cycle, a median number of 10 x 10(6)/kg CD34+ cells (range 8-30) were collected. The median number of apheresis procedures was 1 (range 1-3). From cycle 2 to cycle 4, the median number of days when there was an absolute neutrophil count of less than 500/microl increased from three to five, and the median number of days when the platelet count was less than 25,000/microl increased from three to six. Episodes of febrile neutropenia occurred in 36%, 50% and 46% of cycles during cycles 2, 3 and 4, respectively. The median numbers of days between cycle 1 and cycle 2, cycle 2 and cycle 3, cycle 3 and cycle 4 were 24 (range 20-30), 22 (range 20-36) and 22 (range 18-35), respectively. There were no treatment-related deaths. Non-hematologic toxicity included severe (WHO grades 3 or 4) nausea/vomiting in 19 (18%) cycles, mucositis in 8 (7%) cycles and diarrhea in 7 (6%) cycles. CONCLUSION: Support with hematopoietic progenitor cells and growth factors allows the timely administration of repetitive cycles of high-dose chemotherapy in chemotherapy-naive patients, resulting in a significant increase in dose intensity. Toxicity is noteworthy but manageable and does not compromise further therapy.

Adolescent

Squamous cell carcinoma of the penis: multivariate analysis of prognostic factors and natural history in monocentric study with a conservative policy.

BACKGROUND: Penile carcinoma is uncommon in Western countries. Here we report on a large series of patients with squamous cell carcinoma (SCC) of the penis, describing prognostic factors, survival and therapeutic results. PATIENTS AND METHODS: From 1973 to 1993, 102 patients with invasive SCC of the penis were treated at the Institut Gustave-Roussy. Precancerous lesions and conditions associated with penis cancer were analyzed retrospectively. Survival curves were estimated by the Kaplan-Meier method, and groups were compared for outcome by the log rank test for univariate comparisons and by Cox's proportional hazards model for multivariate analysis. RESULTS: The median age at onset was 58 years. Sixty-nine patients presented with Jackson's stage I disease, 17 with stage II and 15 with stage III. The interval between the manifestation of symptoms and the diagnosis was more than a year in 13.7% of cases. Precancerous lesions were found in 17 (16.6%) patients, and a history of phimosis was noted in 25 (24.5%). In situ and invasive carcinoma were observed together in 17 (16.6%) cases and dysplasia was associated with invasive carcinoma in eight (7.8%) further cases. Conservative treatment was administered whenever feasible. Interstitial brachytherapy was performed alone or associated with limited surgery (local excision or circumcision) in 72 (70.6%) patients. Of the 28 patients with a local relapse, nine have died of their neoplasms (32%) compared to 21 of 28 patients with lymph node relapse (75%). The median follow-up was 111 months. Disease-free survival, disease-specific survival and overall survival were, respectively, 56%, 72% and 63% at five years and 42%, 66% and 50% at 10 years. Age (P = 0.01), the N status (P < 0.00001) or palpable nodes (P < 0.0038), corpus involvement (P = 0.006) and a verrucous histology (P = 0.038) had significant prognostic relevance for survival in the univariate analysis whereas the performance status, T status and Broders' grade did not. In the multivariate analysis only two parameters, involvement of the corpus (P < 0.0001) and palpable nodes (P = 0.009), were singled out as being independent variables influencing survival. A subgroup of nine patients with verrucous histologies were distinguished by their freedom from node involvement. These patients had an excellent prognosis: all are alive and disease-free. Penile integrity was preserved during follow-up in 54 patients (52.9%), 31 of whom are still alive. Of 72 patients treated by a conservative approach including brachytherapy, long-term penile integrity was maintained in 49 (68%). CONCLUSION: Corpus involvement and clinically palpable nodes are highly statistically significant independent factors influencing overall survival. Node relapses remain a major cause of death. Thus, better management of lymph nodes is essential for improving survival even when conservative therapy is used to treat the primary.

Adult

Multistage designs for phase II clinical trials: statistical issues in cancer research.

The main objective of phase II clinical trials is to estimate treatment efficacy on a relatively small number of patients in order to decide whether the treatment ought to be studied in large-scale comparative trials. They play a key role in the drug development process, since the results determine whether or not to proceed to phase III trials. Multistage designs for phase II clinical trials proposed by Gehan, Fleming, Simon and Ensign are described and compared. Gehan's and Simon's designs have two stages, Fleming's designs can have two or more stages, and Ensign's three-stage design combines the first stage of Gehan with the two stages of Simon. Phase II clinical trial protocols and reports should include a description of the design selected with a justification for the particular choice. The present practice is very far from this ideal.

Clinical Trials, Phase II as Topic

High-dose chemotherapy in germ-cell tumors.

The majority of patients with advanced-stage germ-cell tumor are curable by cisplatin-based chemotherapy, but about 10% of those in the good-risk and 30%-50% in the poor-risk groups will experience relapse. Patients in first relapse have a 60% chance of entering a second complete remission and a 15%-25% probability that it will be durable. Regimens of high-dose chemotherapy with hematopoietic stem-cell support have been developed specifically for this patient population; they are usually based on combinations of etoposide, cyclophosphamide, ifosfamide and, originally, double-dose cisplatin or, nowadays, high-dose carboplatin. The role of high-dose chemotherapy was studied initially in salvage and later in first-line treatment. Four hundred thirty-six patients who received high-dose salvage chemotherapy have been reported, 96 (22%) of whom have obtained long-term complete remissions. Prognostic factors for outcome were disease status (absolute refractory, refractory or sensitive diseases), primary tumor site, response to prior chemotherapy and serum hCG levels prior to high-dose treatment. Patients with no adverse prognostic factors have a greater than 50% chance of cure after high-dose treatment. Patients with refractory disease did not benefit from high-dose chemotherapy. A randomized European trial is ongoing to evaluate prospectively the role of high-dose chemotherapy in comparison to standard ifosfamide-based salvage treatment. In first-line consolidation treatment of poor-risk non-seminomatous germ-cell tumors, the results of phase II trials with carboplatin-based high-dose therapy are in favor of a survival impact when compared to historical controls. A prospective randomized trial is ongoing in the US to study the role of carboplatin-based high-dose consolidation treatment. The only prospective trial comparing a cisplatin-based high-dose treatment to standard chemotherapy failed to demonstrate any survival advantage for the high-dose procedure in this setting. New developments include the use of repeated cycles of high-dose chemotherapy with peripheral blood stem-cell support and the introduction of paclitaxel, a new active drug in this disease, and other non-cross-resistant cytotoxic agents in high-dose combination regimes.

Antineoplastic Combined Chemotherapy Protocols

High-dose chemotherapy as salvage treatment in germ cell tumors: a multivariate analysis of prognostic variables.

PURPOSE: To identify prognostic variables for response and survival in male patients with relapsed or refractory germ cell tumors treated with high-dose chemotherapy (HDCT) and hematopoietic progenitor cell support. PATIENTS AND METHODS: Three hundred ten patients treated with HDCT at four centers in the United States and Europe were retrospectively evaluated. Univariate and multivariate analysis of patient, disease, and treatment characteristics were used for comparisons of response rates and failure-free survival (FFS). RESULTS: The actuarial FFS rate was 32% at 1, 30% at 2, and 29% at 3 years. Multivariate analysis identified progressive disease before HDCT, mediastinal nonseminomatous primary tumor, refractory or absolute refractory disease to conventional-dose cisplatin, and human chorionic gonadotropin (HCG) levels greater than 1,000 U/L before HDCT as independent adverse prognostic variables for FFS after HDCT. These variables were used to identify patients with good, intermediate, and poor prognoses. In the good-risk category, the predicted FFS rate at 2 years was 51%, compared with 27% and 5% in the intermediate-risk and poor-risk categories (P < .001). The increased risk for treatment failure was due to both a significantly lower rate of favorable responses and a significantly higher rate of relapses. Within the prognostic categories, the particular HDCT regimen or higher dosages of carboplatin or etoposide did not have a significant influence on treatment outcome. CONCLUSION: Prognostic variables for treatment response after HDCT can be identified. The proposed prognostic model might help to optimize the use of HDCT in germ cell tumors and warrants validation in future trials.

Antineoplastic Combined Chemotherapy Protocols

[Research design for patient selection in clinical trials phase II].

Phase II trials play a key role in the development of a treatment, because they are crucial in deciding whether or not to proceed to phase III. In the event of the evaluation of a new treatment given to only one group of subjects, multi-stage designs were developed to include subjects in phase II trials. Gehan's two stage designs stop inclusion of subjects if no success is observed among the first n1 subjects. They are easy to use, but have the disadvantage of exposing many subjects to an inefficient treatment at the second stage. Fleming's multi-stage designs and Simon's two stage designs permit the early termination of a trial when the intermediate results are extreme, either in favor of the efficiency or in favor of the inefficiency of the treatment. Simon's plans minimize either the average or the maximum number of subjects exposed to ineffective treatment. Ensign's three stage designs combine the first stage of Gehan with the two stages of Simon. These plans are interesting because they can reject a treatment quickly after a long run of failures which minimizes the average number of subjects exposed to an ineffective treatment.

Bias

Non-parametric methods for analysing recurrent complications of varying severity.

Non-parametric methods have recently been proposed to take into account the recurrent nature of complications in clinical trials, by estimating the prevalence Q(t), defined as the probability of relapse-free patients being in a complication state at time t. Recoveries are also considered. These methods have been adapted in this paper to take into consideration not only the recurrent nature of complications but also their severity through the interpretation of average weight functions. Results of a randomized trial comparing late complications following two alternative doses of pre-operative internal brachytherapy in patients with localized stage cervix carcinoma are used to illustrate the methods.

Brachytherapy

Adequate locoregional treatment for early breast cancer may prevent secondary dissemination.

PURPOSE: To analyze different events that determine event-free survival (EFS) in a randomized trial on adjuvant radiotherapy in early breast cancer patients with more than 15 years of follow-up evaluation. PATIENTS AND METHODS: The trial included 960 patients with a unilateral, operable breast cancer. Surgery consisted of a modified radical mastectomy. The trial compared three arms, as follows: preoperative radiotherapy, postoperative radiotherapy, and no adjuvant treatment. Events were analyzed by a competing-risk approach. A proportional hazards multiple regression model was used to analyze the effects of radiotherapy on the risk of distant metastasis. Similar analyses were performed separately for node-negative [N(-)] and node-positive [N(+)] patients in the two groups that did not include preoperative radiotherapy. RESULTS: Radiotherapy produced a fivefold decrease of the risk of local recurrence (P < .0001). In N(+) patients, postoperative radiotherapy decreased the risk of distant dissemination (relative risk, 0.63). When local recurrence was introduced in the model as a time-dependent covariate, this factor was predictive of distant dissemination (P < .0001) and nullified the effect of postoperative radiotherapy. This finding suggests that the decrease of distant metastases was related to the prevention of local recurrence. A similar effect was found in models that used overall survival as an end point. CONCLUSION: This study shows that postmastectomy radiotherapy in N(+) breast cancer patients may decrease the distant metastasis rate by preventing local recurrences and thus avoiding secondary dissemination.

Breast Neoplasms

Analysis of complications in a prospective randomized trial comparing two brachytherapy low dose rates in cervical carcinoma.

PURPOSE: The analysis of complications in a prospective randomized trial comparing two preoperative brachytherapy low-dose rates in early stage cervical cancer is presented. METHODS AND MATERIALS: Between 1985 and 1988, 204 patients with Stage I and limited Stage II cervical cancer were randomized to receive one of two preoperative brachytherapy low-dose rates (0.4 and 0.8 Gy/hr). The objective of this trial was to determine the benefits, if any, of the higher-dose rate within the therapeutic arsenal for this patient population, in terms of survival, local control, and complications. The type and severity of all complications were evaluated according to a common glossary and a strict follow-up schedule was established given that the treatment of cervical cancer is multidisciplinary, involving gynecologists, surgeons, and radiotherapists. RESULTS: Overall survival: 85% at 2 years and local control: 93% at 2 years, were similarly distributed between the two groups. Regardless of their nature and severity, 139 and 175 complications were observed among 63% and 75% of patients, in the 0.4 and 0.8 Gy/h dose rate groups respectively. Gynecologic and urinary complications were the most frequent (38% and 28% of all complications), followed by vascular (15%), digestive (10%), nervous (5%) and cutaneous (5%). A total of 14 and 17 severe complications (Grade 3) were observed in 7% and 13% of patients, respectively in the 0.4 and 0.8 Gy/h dose rate groups (p = 0.12). Nonparametric survival methods used to compare the time to the first complication did not show a significant difference between the two groups: 62% and 72% at 2 years (p = 0.27). When the first complication and its evolution were considered (early complications), the prevalence of complications was not significantly different between the two groups: 28% vs. 34% at 2 years (p = 0.31). In this prospective trial, patients were regularly followed-up and complications of varying nature and severity were observed in succession during follow-up. When successive complications and their evolution were taken into account, the prevalence of complications was significantly greater in the higher-dose rate group: 30% vs. 45% at 2 years (p = 0.03). CONCLUSION: The results of this trial showed that long-term effects of treatment, when represented by prevalence of complications over time, were more frequent in the higher dose rate group. This underlines the importance of the regular follow-up of patients and of coding, not only the occurrence of all complications, but also their evolution over time.

Brachytherapy

Acute tumor lysis syndrome in poor-risk germ cell tumors: does it exist?

Acute tumor lysis syndrome (ATLS) is a well-known adverse event described after effective chemotherapy for extensive, highly proliferative, and chemosensitive tumors. While its occurrence with hematological malignancies is frequently described, there have been scattered case reports documenting ATLS in solid tumors. However, such events have not been reported in poor-risk germ cell tumors. We reviewed retrospectively 46 cases of such tumors treated in our department between 1988 and 1993 by aggressive cisplatin-based chemotherapy. All patients received systematically 6 l/24 h hydration according to the cisplatin- protocol administration. Blood chemistry data for potassium, phosphorus, calcium, alkaline reserve, uric acid, creatinine and lactate dehydrogenase were obtained before treatment and during the 7 days of the induction chemotherapy. No metabolic abnormalities suggestive of ATLS were observed. Nevertheless, 2 patients with bulky disease of the chest experienced early death from respiratory distress complicated by multiorgan failure. ATLS seems to be an unlikely event in poor-risk germ cell tumors and therefore special prophylactic therapy may be unnecessary.

Acute Disease

Prognostic factors and survival in patients with metastatic renal cell carcinoma treated with chemotherapy or interferon-alpha.

Prognostic factors and survival were analysed in 295 patients with metastatic renal cell carcinoma (MRCC), treated with either chemotherapy (1975-1990) or interferon (IFN) (1983-1990). The 3-year survival was 8 and 24% in the chemotherapy and IFN groups, respectively (P < 0.001). In the univariate analysis, age < or = 60 years, prior nephrectomy, more than 1 year since initial diagnosis and treatment for metastatic disease, ECOG performance status 0 or 1, absence of liver metastases, lower erythrocyte sedimentation rate (first hour), and < or = 10% weight loss, within the past 6 months, were correlated with improved survival. Sedimentation rate, performance status and weight loss remained independent prognostic factors from the results of a Cox regression analysis. Three prognostic groups were identified from a combination of these factors. In the poor and intermediate risk groups, no significant survival difference was observed between patients treated with chemotherapy and those treated with IFN. The 3-year survival estimates for good risk patients were 15 and 48% in the chemotherapy and IFN groups, respectively. Therefore, in MRCC, sedimentation rate, performance status and weight loss are easily assessable and reproducible prognostic variables for the identification of risk groups. We hypothesise that IFN may increase survival in good risk patients, but is as ineffective as chemotherapy in poor risk patients with MRCC.

Adult

A comparison of early effects with two dose rates in brachytherapy of cervix carcinoma in a prospective randomised trial.

This phase III randomised trial examined the early effects of two low dose rates (0.38 and 0.73 Gy/h) in brachytherapy of stage I and IIp cervical cancer patients. A total of 204 patients were included between January 1985 and September 1988. Since the main analysis of this paper concerned surgical difficulties, only the 155 patients (76%) on whom surgery was performed at the Institut Gustave-Roussy were retained in this analysis. Treatment consisted of uterovaginal 137Cs irradiation followed by immediate or deferred surgery. The two groups were similar for pretreatment characteristics except for endocervix involvement. Their brachytherapy parameters were also similar (60 Gy pear dimensions, doses to critical organs, total kerma, etc.). The factors with a poor prognosis were, for surgical difficulties, older age, stage II and a small irradiated pear volume; for difficulties with haemostasis, immediate surgery, stage II and previous surgery; and for difficulties in dissection, lymph node involvement. The dose rate significantly influenced surgical difficulties for the stage IIp patients operated on by deferred surgery. Those treated with the higher dose rate showed a 2-fold increase in surgical difficulties compared to those irradiated at the lower dose rate (P = 0.03). The independent prognostic factors for sterilisation of the surgical specimen were small tumour size and absence of lymph node involvement. An inverse dose rate effect was observed for medium size tumours, with significantly more sterilisations observed in stage IIp patients in the lower dose rate group (P < 0.01).

Adult