This article summarizes the current status of 1H MRS in detecting and quantifying a boron neutron capture therapy (BNCT) boron carrier, L-p-boronophenylalanine-fructose (BPA-F) in vivo in the Finnish BNCT project. The applicability of 1H MRS to detect BPA-F is evaluated and discussed in a typical situation with a blood containing resection cavity within the gross tumour volume (GTV). 1H MRS is not an ideal method to study BPA concentration in GTV with blood in recent resection cavity. For an optimal identification of BPA signals in the in vivo 1H MR spectrum, both pre- and post-infusion 1H MRS should be performed. The post-infusion spectroscopy studies should be scheduled either prior to or, less optimally, immediately after the BNCT. The pre-BNCT MRS is necessary in order to utilise the MRS results in the actual dose planning.
The risk of cardiac injury with hypofractionated whole-breast/chest wall radiation therapy (HF-WBI) compared with conventional whole-breast/chest wall radiation therapy (CF-WBI) in women with left-sided breast cancer remains a concern. The purpose of this study was to determine if there is an increase in hospital-related morbidity from cardiac causes with HF-WBI relative to CF-WBI.
Between 1990 and 1998, 5334 women = 80 years of age with early-stage breast cancer were treated with postoperative radiation therapy to the breast or chest wall alone. A population-based database recorded baseline patient, tumor, and treatment factors. Hospital administrative records identified baseline cardiac risk factors and other comorbidities. Factors between radiation therapy groups were balanced using a propensity-score model. The first event of a hospital admission for cardiac causes after radiation therapy was determined from hospitalization records. Ten- and 15-year cumulative hospital-related cardiac morbidity after radiation therapy was estimated for left- and right-sided cases using a competing risk approach.
The median follow-up was 13.2 years. For left-sided cases, 485 women were treated with CF-WBI, and 2221 women were treated with HF-WBI. Mastectomy was more common in the HF-WBI group, whereas boost was more common in the CF-WBI group. The CF-WBI group had a higher prevalence of diabetes. The 15-year cumulative hospital-related morbidity from cardiac causes (95% confidence interval) was not different between the 2 radiation therapy regimens after propensity-score adjustment: 21% (19-22) with HF-WBI and 21% (17-25) with CF-WBI (P=.93). For right-sided cases, the 15-year cumulative hospital-related morbidity from cardiac causes was also similar between the radiation therapy groups (P=.76).
There is no difference in morbidity leading to hospitalization from cardiac causes among women with left-sided early-stage breast cancer treated with HF-WBI or CF-WBI at 15-year follow-up.
BACKGROUND: The recently published, widely publicized adjuvant radiation trials from Denmark and Canada concluded that the addition of postoperative radiotherapy (XRT) to modified radical mastectomy (MRM) and adjuvant chemotherapy reduces locoregional recurrences and prolongs survival in high-risk premenopausal patients with breast cancer. Our thesis is that adequate lymphadenectomies were not performed in either study. Consequently, the conclusion to these studies is not applicable to those patients who have undergone adequate surgery. METHODS: To better assess adequate lymph node yield from an MRM, a retrospective review was performed on 215 consecutive patients treated surgically for invasive breast cancer. Data from this review were compared with the surgical data from the above-mentioned radiotherapy trials. RESULTS: In a group of 131 patients who had MRM, the average number of nodes removed was 26 (median, 25), and 75.5% of the specimens had 20 or more lymph nodes. In 73 patients who underwent segmental mastectomy with axillary lymph node dissection, both the average and the median number of lymph nodes removed were 24, and 68.9% had 20 or more nodes. These data compare to the Danish radiation trial in which a median of 7 lymph nodes were removed (with 76% of the patients having 9 or fewer lymph nodes in the specimen) and to the Canadian radiation trial in which a median of 11 lymph nodes were removed. In addition, in our breast cancer patients with positive nodes (84 of 204; 41.2%), 45.2.% (38 of 84) had more than three positive nodes compared with 29.8% in the Danish study and 35% in the Canadian study. CONCLUSIONS: Our surgical data are sufficiently different from those of the Danish and Canadian studies to indicate that, in those studies, incomplete lymph node dissections were performed and that residual disease was left behind in the axilla in some or all of the patients. The addition of XRT in the setting of residual axillary disease may compensate for an inadequate operation and yield an acceptable oncological result; however, these studies did not provide an adequate comparison with a well-performed MRM without XRT. In the absence of documented benefit, XRT should not be routinely added if a complete lymph node dissection has been performed.
Radiotherapeutical resources in Norway are inadequate, which was further verified in this retrospective study of 73 patients with cancer of head and neck. The average duration of symptoms before the first ear-nose-throat examination was 153 days, and it took about 10 days after the examination to get the diagnosis. An unacceptably long time (mean 30 days) elapsed between the decision on therapy until the radiotherapy was initiated. There is no doubt that radiotherapy departments in Norway need better resources.
Current estimates of the proportion of cancer patients who will require radiotherapy (RT) are based almost entirely on expert opinion. The objective of this study was to calculate the proportion of incident cases of cervical cancer that should receive RT by application of an evidence-based approach.
A systematic review of the literature was done to identify indications for RT for cervical cancer and to ascertain the level of evidence that supported each indication. A survey of Canadian gynecologic oncologists and radiation oncologists who treat cervical cancer was done to determine the level of acceptance of each indication among doctors who practice in the field. An epidemiologic approach was then used to estimate the incidence of each indication for RT in a typical North American population of patients with cervical cancer.
The systematic review of the literature identified 29 different indications for RT for cervical cancer. The majority of the 75 experts who responded to the mail survey stated that they "usually" or "always" recommended RT in all but one of the clinical situations that were identified as indications for RT on the basis of the systematic review. The analysis of epidemiologic data revealed that, in a typical North American population, 65.4% +/- 2.5% of cervical cancer cases will develop one or more indications for RT at some point in the course of the illness, 63.4% +/- 2.3% will develop indications for RT as part of their initial management, and 2.0% +/- 0.9% will develop indications for RT for progressive or recurrent disease. The effects of variations in case mix on the need for RT was examined by sensitivity analysis, which suggested that the maximum plausible range for the appropriate rate of utilization of RT was 54.3% to 67.9%. The proportion of cases that required RT was stage dependent: 10.6% +/- 1.2% in Stage IA, 74.9% +/- 1.3% in Stage IB, 100% in Stages II and III, and 97.2% +/- 1.1% in Stage IV.
This evidence-based estimate of the appropriate rate of use of RT for cervical cancer adds to the growing pool of knowledge about the need for RT that will ultimately provide a rational basis for long-term planning for RT programs and for auditing access to RT in the general population.
After surgical resection for oral cavity squamous cell carcinoma, adjuvant radiotherapy may be recommended for patients at higher risk for locoregional recurrence, but it can be difficult to predict whether a particular patient will benefit.
To construct a model to predict which patients with oral cavity squamous cell carcinoma would benefit from adjuvant radiotherapy.
We constructed several types of survival models using a set of 979 patients with oral cavity squamous cell carcinoma. Covariates were age, sex, tobacco use, stage, grade, margins, and subsite. The best performing model was externally validated on a set of 431 patients.
The model was based on a set of 979 patients with oral cavity squamous cell carcinoma, including 563 from Memorial Sloan Kettering Cancer Center, New York, New York, and 416 from the Hospital AC Camargo, São Paulo, Brazil. The validation set consisted of 431 patients from Princess Margaret Hospital, Toronto, Ontario, Canada.
The primary outcome measure of interest was locoregional recurrence-free survival.
The lognormal model showed the best performance per the Akaike information criterion. An online nomogram was built from this model that estimates locoregional failure-free survival with and without postoperative radiotherapy.
A web-based nomogram can be used as a decision aid for adjuvant treatment decisions for patients with oral cavity squamous cell carcinoma.
The variability in target delineation for similar cases between centres treating paediatric and adolescent patients, and the apparent differences in interpretation of radiotherapy guidelines in the treatment protocols encouraged us to perform a dummy-run study as a part of our quality assurance work. The aim was to identify and quantify differences in the segmentation of target volumes and organs at risk (OARs) and to analyse the treatment plans and dose distributions.
Four patient cases were selected: Wilm's tumour, Hodgkin's disease, rhabdomyosarcoma of the prostate and chordoma of the skull base. The five participating centres received the same patient-related material. They introduced the cases in their treatment planning system, delineated target volumes and OARs and created treatment plans. Dose-volume histograms were retrieved for relevant structures and volumes and dose metrics were derived and compared, e.g. target volumes and their concordance, dose homogeneity index (HI), treated and irradiated volumes, remaining volume at risk and relevant Vx and Dx values.
We found significant differences in target segmentation in the majority of the cases. The planning target volumes (PTVs) varied two- to four-fold and conformity indices were in the range of 0.3-0.6. This resulted in large variations in dose distributions to OARs as well as in treated and irradiated volumes even though the treatment plans showed good conformity to the PTVs. Potential reasons for the differences in target delineation were analysed.
Considerations of the growing child and difficulties in interpretation of the radiotherapy information in the treatment protocols were identified as reasons for the variation. As a result, clarified translated detailed radiotherapy guidelines for paediatric/adolescent patients have been recognised as a way to reduce this variation.
Post-lumpectomy breast radiation is the standard of care for all patient subgroups. However, elderly women with stage I breast cancer on adjuvant tamoxifen therapy have a 4% risk of local recurrence after lumpectomy without adjuvant breast radiation. The purpose of this study was to explore the attitudes of Canadian radiation oncologists who treat breast cancer with respect to their use of adjuvant post-lumpectomy radiotherapy, and their willingness to implement a decision aid for this patient population.
The questionnaire was mailed to 141 Canadian radiation oncologists who treat breast cancer. The respondents were asked to complete an online survey consisting of four parts: (1) demographic information; (2) factors determining post-lumpectomy radiation treatment decisions; (3) hypothetical case scenarios; (4) interest in using a decision aid in their practice.
Among the 61 (43%) physicians who completed the survey, there was substantial response variation. After contraindications to radiotherapy, patient overall health and patient preference had the greatest influence on their decision to offer radiotherapy to this patient subgroup. Margin status and use of hormonal therapy were given less importance. For each of the case scenarios, 60-83% of physicians (depending on the case scenario) would offer the patient a choice; far fewer (12-57%) would be comfortable not irradiating. Sixty-four per cent of respondents welcomed the concept of a decision aid for this population.
Although there is significant variation in practice patterns and attitudes among radiation oncologists regarding post-lumpectomy radiotherapy for elderly, low-risk breast cancer patients, the vast majority value patient choice and would be willing to use a decision aid designed for this population in their practice.
To explore physician recommendations regarding radioiodine remnant ablation (RRA) as adjuvant treatment in early-stage well-differentiated thyroid carcinoma (WDTC), their rationale for administration of RRA, and their willingness to involve patients' opinions in decision making about the use of RRA.
We surveyed a representative sample of specialty physicians in Canada and the United States and asked survey participants whether they would recommend adjuvant RRA after thyroidectomy for a 1.6-cm papillary thyroid carcinoma (Likert scale of agreement responses from 1 to 7; strong agreement >or=6). Factor analysis was performed to explore the rationale for recommendations. We asked whether physicians accepted the role of patients' preferences in decision making about administration of RRA, and backward conditional logistic regression analysis was used to identify predictors of strong acceptance.
The effective response rate for the survey was 56.3% (486 of 864), with 62.8% (295 of 470 respondents) strongly recommending RRA. Strong RRA recommendations were founded in opinions that RRA (1) decreases WDTC-related mortality and recurrence and (2) facilitates WDTC follow-up at low risk of adverse effects. Approximately a third of the survey respondents (152 of 474) strongly agreed with incorporation of patients' preferences in decision making regarding the use of RRA. Physicians without firm convictions about the efficacy of RRA in decreasing disease-related outcomes and those practicing in the United States were most likely to indicate strong support for incorporating patients' preferences in decision making about RRA.
The recommendations of physicians regarding use of adjuvant RRA are founded in beliefs in intervention efficacy and follow-up practices. Physicians in medical practice in the United States and those without strong convictions about RRA efficacy are most likely to incorporate patients' views in individualizing decisions about RRA therapy.
To identify risk factors associated with an increased risk for ipsilateral breast tumor recurrence following breast-conserving surgery, a cohort of 759 women with T1-T2 tumors were studied. The majority of the patients (88%) had received postoperative radiation therapy to the breast. Median follow-up time was 10 (range: 6-17) years. There was a 1-1.5% yearly increase in ipsilateral breast tumor recurrences. For women or = 50 ys, 9%. Node positive women had a cumulative breast recurrence rate of 25% versus 10% for node negative women. Ten years postoperatively, irradiated patients had a cumulative recurrence rate of 11% versus 26% when no irradiation was given. The beneficial effect of radiotherapy was substantial during the first four postoperative years. The relative risk for an ipsilateral breast tumor recurrence during this period was 4.5 times higher than for non-irradiated patients. However, the protective effect of radiotherapy decreased with time. After ten years the relative risk of ipsilateral breast tumor recurrence was the same among irradiated and non-irradiated patients although the number of events during this period was low. Univariate analysis showed that seven factors were significantly associated with an increased risk of ipsilateral breast tumor recurrence, namely age or = 50 were a low risk-group for ipsilateral breast tumor recurrence, with a cumulative risk at 10 years of 9% without radiation therapy and 5% with breast irradiation.