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Purpose: To evaluate the ability of magnetic resonance (MR) imaging enhanced with AMI-25 to depict and characterize hepatic tumors., Materials and Methods: Sixty-four patients (41 men and 23 women, aged 24-65 years [mean, 55 years]) underwent 1-T MR imaging: 22 had metastatic disease; 10, hepatocellular carcinoma; seven, hemangioma; three, focal nodular hyperplasia; three, gallbladder adenocarcinoma; two, lymphoma; one, adenoma; and 16, no tumor. Pre- and postcontrast images (alone and in combination) were analyzed by three independent radiologists. Receiver operating characteristic curves were constructed to compare tumor characterization., Results: Signal intensity was decreased in all benign tumors but not in malignant tumors. The number of tumors depicted (nonenhanced images, 657 tumors; enhanced, 753; and combined, 760) was not statistically different. Receiver operating characteristic curves did not show improved characterization with AMI-25., Conclusion: AMI-25 does not improve depiction of hepatic tumors. Although characterization of hepatic tumors was not improved with AMI-25, uptake of AMI-25 seems specific for hepatic tumors at MR imaging.

Purpose: This present review is intended to evaluate the specific influence of fractionation of total body irradiation on the outcome of a subsequent bone marrow transplantation., Methods and Materials: Available experimental and clinical data on the influence of fractionation on leukemia cell killing, immunosuppression, and sparing of normal tissues were analyzed., Results: Review of available data shows: (a) The role of fractionation on leukemia cell killing may vary with the leukemia type. For acute nonlymphoblastic leukemia, a few experimental and several clinical studies show no or little fractionation effect; a 12-13 Gy fractionated scheme could, therefore, be more efficient than a conventional 10 Gy single dose total body irradiation. For chronic myelogenous leukemia, some sensitivity to fractionation is suggested, so that an increase in total or fractional dose may be necessary in fractionated schemes to equate the efficacy of a 10 Gy single dose. For acute lymphoblastic leukemia, a high fractionation sensitivity was observed for some leukemic cell lines in vitro, without undisputable clinical confirmation for the moment. (b) Numerous experimental studies have demonstrated that the immunosuppressive effect of total body irradiation, a major determinant of engraftment, is highly fractionation sensitive. In humans, high rates of graft failures have been reported when T-cell depletion of the graft was associated to fractionated total body irradiation schedules. (c) A large amount of radiobiological and clinical data have demonstrated that late radiation-induced injuries to normal tissues and organs are highly fractionation sensitive. However, in a context of total body irradiation for bone marrow transplantation, the number of other determinants of normal tissue damage makes it difficult to demonstrate a clear-cut advantage of fractionated over single dose scheme, with a possible exception for children., Conclusions: In 1994, available data suggest that very cautious attempts could be made to adapt total body irradiation schedules to the potential normal tissue toxicity, T-cell depletion, and to the type of leukemia.

In 1994, late effects of radiotherapy should be limited to an acceptable rate of benign and non-disabling complications. In almost all cases, this goal can be presently reached, owe to recent technological and radiobiological advances. The precise adaptation of irradiated volume, dose, fractionation and total duration of treatment should avoid severe post-radiotherapeutic toxicity. The identification of subgroups of patients with high susceptibility to ionizing radiations should soon allow the radiotherapists to take up the challenge of a both efficient and non-toxic irradiation.

A total of 68 men (mean age 66.2 years) were treated for a primary carcinoma of the breast at Mount Vernon Hospital between January 1968 and June 1988. The mean duration of the symptoms before diagnosis was 13.3 months. The most common sign of presentation (60% of the patients) was a mass in the breast (mean size 3.9 cm). Thirty-three tumours (48.5%) were fixed to the skin and in nine the skin was ulcerated. Sixty-nine per cent of the patients had a T4 tumour and 51.5% had a palpable axillary node. Thirteen patients (19%) were treated by radiotherapy alone, 46 (67%) by surgery and postoperative radiotherapy, and nine (13.3%) by surgery alone. Sixty patients (88%) were in complete remission after the initial treatment and seven of these (12%) developed a local recurrence. The median follow-up was 54 months. The overall survival was 23% at 10 years and the corrected survival 42% at 10 years. Patients with no nodal disease at presentation had a better survival than those with N1 or N2 disease (55% versus 22% 10 years corrected survival, P < 0.002). The risk of nodal disease was strongly correlated by univariate analysis with the size of the tumour (P = 0.002) and the skin fixation (P = 0.005). The risk of metastatic dissemination was correlated with the nodal clinical involvement (P = 0.02) and the existence of a local recurrence (P = 0.003). In multivariate analysis, T and N stages were significantly associated with an increasing risk of treatment failure (P = 0.01). Forty-seven per cent of the patients with T4 tumours developed metastatic disease. This emphasizes the need for adjuvant systemic treatment for these patients.

Despite the obvious breakthrough of high dose-rate (HDR) afterloading systems on the gynecological brachytherapy market, questions still remain regarding the transfer of available expertise gained throughout the last 80 years with low dose-rate (LDR) radium and cesium, especially regarding the conversion of LDR total dose into equivalent HDR dose per fraction and total dose. Calculation of biologically equivalent schedules requires a knowledge of repair capacity and repair kinetics of tumors and normal tissues, both of which influence the biological effect of any radiation dose. The clinical experience with HDR is, however, accumulating and it is acknowledged that the new technique entails an acceptable therapeutic index as compared to the classical LDR. There is thus a state of apparent 'equivalence' between the two treatment modalities. This state is influenced by many factors in which, in contrast to what is frequently claimed, radiobiological factors do not play the most important role. It is probably its high-tech environment which makes HDR an acceptable alternative. Treatment at LDR, indeed, has proven to be quite tolerant to a lack of absolute precision, something that would be disastrous with HDR techniques. Because HDR intracavitary brachytherapy has not been compared in controlled trials with the best existing LDR brachytherapy, but only retrospectively with heterogeneous LDR clinical data, it cannot be claimed to be equivalent, but simply feasible.

Class I and II HLA typing was investigated before and at various intervals after a 10 Gy total body irradiation delivered over 4 h, prior to allogeneic bone marrow graft for various hematological malignancies, in 14 patients. A reliable class I HLA typing appeared to be possible in almost all cases 6-8 hours after the start of irradiation but was only possible in 5 patients after 24 h. Preliminary results with class II antigens might suggest a more marked "fragility" of this antigen class after irradiation. These results encourage the drawing of blood samples for HLA grouping as soon as possible after accidental whole-body irradiation.

Thirty-one selected patients with various haematological malignancies who received a 10 Gy-4 h total body irradiation (TBI) at the Institut Gustave Roussy 24 h before high dose cyclophosphamide for bone marrow transplantation, were prospectively evaluated for gastrointestinal symptoms, body temperature, consciousness, headache, xerostomia, parotiditis, ocular symptoms, blood pressure, and respiratory and cutaneous signs for 24 h. In spite of prophylactic administration of various anti-emetic agents, 90% of the patients experienced nausea and 80% experienced vomiting. An almost constant body temperature peak--up to 40.8 degrees C--was registered 6 h after the start of irradiation. No drowsiness was reported since the introduction of the new anti-emetic agent Ondansetron. Nearly half the patients (42%) complained of headache. The proportion of patients experiencing early (during TBI) xerostomia was 61%. 74% of patients complained of parotiditis in the first 24 h. Although this low dose rate whole body irradiation is not likely to be exactly replicated in many accidental human exposures, the incidence rate and the time-course of the observed prodromal phase symptoms may prove helpful for early triage in the case of accidental irradiation.

Purpose: to assess mouse rectum tolerance to fractionated X-ray and neutron irradiation., Materials and Methods: doses per fraction ranged between 0.25 and 35 Gy for X-rays, 0.05 and 12 Gy for neutrons. Neutron top-up doses were added when the fractionated irradiation was given in fractions less than 2 Gy of X-rays or 0.35 Gy of neutrons in order to bring the damage into the detectable range. The early endpoints were the nadir of weight loss occurring within the first 2-3 weeks following irradiation and lethality by 2 months. The late endpoints were the peak of weight reached at maturity of the mice, the proportion of short feces in the daily fecal output at 10 months and lethality by 12 months. The linear-quadratic (LQ) model was fitted to the data (direct "one-step" analysis) and the estimated parameters were used to calculate relative biological effectiveness (RBE) values., Results: alpha/beta ratio estimates were for X-rays: 19.9 Gy [95% confidence limits: 15.2, 27.0] for weight nadir. 13.4 Gy [9.3, 19.5] for early lethality, 6.4 Gy [3.6, 11.0] for peak weight, and 6.9 Gy [4.2, 10.8] for late lethality, for neutrons 19.9 Gy [9.5, 61.0] for peak weight. The fecal-deformity data were poorly fitted by the LQ model. The RBE was slightly higher for acute endpoints than for the late ones when X-ray fraction sizes were equal to or larger than 10 Gy. However, the change in RBE with decreasing X-ray dose per fraction was much steeper for the late endpoints, so that it became equal to or even higher than for acute reactions at doses per fraction of 5 Gy or less., Conclusion: Our results were consistent with those obtained from previously published studies using the same experimental system but larger doses per fraction.

Purpose: To determine whether in vitro radiosensitivity parameters are predictive of treatment outcome., Methods and Materials: Biopsies were obtained from patients with head and neck cancers (57) and cervical carcinomas (20) and in vitro radiosensitivity parameters were obtained using the CAM plate assay., Results: In most cases (75%) patients were treated with radiation alone. The median follow up was 461 days. When the whole group of head and neck cancers and cervical carcinomas was considered, patients with a SF2 value below 0.36 had a higher 2-year local control rate (93% versus 68%) and a higher 2-year survival rate (71% vs. 62%) than those with SF2 values above that threshold, but differences were not significant. These trends persisted when head and neck cancers were considered alone with a higher local control rate (86% vs. 67%) and a higher survival rate (75% vs. 52.5%) obtained for patients with a SF2 value below 0.36. When the alpha value was evaluated for the whole group of patients a significantly higher local control rate (80.5% vs. 40.5%) and overall survival rate (71% versus 37.5%) at 2 years were obtained for patients with alpha values above 0.07 Gy-1. When only the group of head and neck cancers was considered, local control rate was significantly higher (79% vs. 33%) but overall survival rate (65.5% vs. 33%) was not significantly higher for alpha values above 0.07 Gy-1., Conclusion: These results are encouraging but need to be confirmed with a larger number of patients with a longer follow-up.

From 1971 to 1983, 398 (33 T1, 309 T2, 56 T3) biopsy-proven breast adenocarcinomas were treated conservatively at Hôpital Henri Mondor by an initial course of external irradiation (45 Gy, 25 fractions, 5 weeks) followed by interstitial iridium-192 implant for a further 37 Gy to the tumor. The mean interval between external irradiation and brachytherapy was 5.9 weeks (S.D. 1.7, range 1-18). Seventy-seven local failures were observed at 10-148 months (median 34.5). The actuarial probabilities (S.E.) of local control at 5 and 10 years were 0.86 (0.02) and 0.74 (0.03), respectively. The follow-up for patients free of local recurrence was 4-205 months (median 95). Multivariate analysis showed an increasing probability of local failure with longer interval between external irradiation and brachytherapy (Relative Risk [R.R.] 1.23 [95% confidence limits: 1.07, 1.41] per week, p = 0.005), and a lower risk of failure in case of complete tumor regression after external irradiation (R.R. 0.47 [0.25, 0.90], p = 0.022), and higher brachytherapy dose rate (R.R. 0.13 [0.02, 1.02] per Gy/h, p = 0.053). No influence of tumor size and total dose (possibly because only limited variations in total dose were observed), or histological grading (not performed in 140 [35%] patients) was found. Because of the lack of dose-control relationship, quantification of the effects of delay between external irradiation and brachytherapy (in terms of compensatory dose) and of dose rate (Incomplete Repair Model) was not possible.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum alpha-amylase was measured before and 24 h after either total body (31 patients) or localized irradiation including the salivary glands (40 patients) or the pancreatic area (22 patients). A significant increase in amylasemia was observed for doses to the parotid glands larger than 0.5 Gy. A sigmoid function of dose was fitted to the data and predicted a maximum amylasemia level for doses larger than 4 Gy and smaller than 10 Gy. The raw data from other published series were adequately described by the same model. However, the confidence limits of the parameters remained wide, because of a considerable interindividual variability. Post-irradiation hyperamylasemia appears to provide a good criterion for triage of accidentally irradiated patients: 24 h after a dose larger than 2 Gy to the parotid glands, 91% of the patients had an amylasemia level higher than 2.5-fold the upper normal value (sensitivity). Conversely, 96% had their serum amylasemia lower than 2.5-fold the upper normal value when dose was smaller than 2 Gy (specificity). However, a retrospective estimation of the absorbed dose (dosimetry) is not likely to be very precise because of the large interindividual variability.

Prognosis of esophageal cancer is very poor. Five-year survival does not exceed 20% after radical surgery, the best available treatment. Unfortunately, only 40% of the patients are amenable to surgery because of poor general status and/or locoregional extension. Adjuvant treatment did not yield survival improvement. Preoperative radiotherapy (three randomized trials) or postoperative radiotherapy (one randomized trial) showed only a decrease of regional relapses, perhaps only for the nodes negative patients. Neoadjuvant chemotherapy obtains some interesting response rate (20-60%), but there has been no evidence yet for survival improvement. Recently, promising results were presented after combination of radiotherapy and chemotherapy. In this paper, we review the present status of combined treatment for esophageal cancer. Our multicentric group (OSOF) is now completing a phase II trial, that should soon form the basis for a phase III prospective study.

The authors compared the accuracy of spin-echo (SE) and gradient-echo (GRE) magnetic resonance images in diagnosis of abdominal venous thrombosis. Images of 292 abdominal veins in 72 patients were reviewed in a blinded manner by three radiologists, with seven levels of confidence for diagnosis. Corroborative studies proved thrombosis (n = 95) and vessel patency (n = 197). Receiver operating characteristic (ROC) curves were constructed for SE images alone, GRE images alone, and SE and GRE images combined. At specificities of 90% and 95%, thrombi were identified with sensitivities, respectively, of 76% and 63% with SE images, 74% and 58% with GRE images, and 88% and 82% with combined SE and GRE images. The area under the ROC curve for SE and GRE images combined (0.958 +/- 0.011 [standard deviation]) was significantly larger (P less than .001) than that for SE images alone (0.913 +/- 0.018) and GRE images alone (0.921 +/- 0.016). It is concluded that combination of SE and GRE images significantly increases the accuracy of diagnosis of abdominal venous thrombosis.

Tumor clonogenic cell content is believed to play an important role in the outcome of radiotherapy. However, there is no proven method to assess the number of clonogens in human tumors accurately. All currently available assays employ in vitro plating efficiency or in vivo TD50 (the average number of cells needed to induce tumors in 50% of injected mice) to estimate the tumor clonogenic ability. In this study, a monolayer mass primary culture system was used to estimate the clonogenic cell fraction in human tumors. For this purpose, 25 growth curves were performed for 25 tumor specimens derived from 21 head and neck and 4 cervical squamous cell carcinomas. The exponential portion of each growth curve was extrapolated through the ordinate (day 0) to estimate the clonogenic cell fraction; this method is only an estimate because it assumes no lag phase before exponential growth of clonogenic cells. The mean clonogenic cell fraction, expressed as clonogens/tumor cells inoculated, was relatively low (mean: 0.71%, range: 0.11-9.28), and the variation was wide (coefficient of variation = 148%). On the other hand, the doubling time of the growing population was 1.46 days and exhibited a very narrow range (0.98-2.24, coefficient of variation = 24%). The mean and range of clonogenic cell fraction were found to be in agreement with published values of soft agar colony forming efficiencies in both murine and human tumors. However, further investigation is necessary to determine how accurately this method measures the relative clonogenic cell content in human tumors. Clinical correlations between clonogenic cell fraction values and the response to radiotherapy are still too early to determine.