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Aims: To investigate intensity-modulated radiotherapy (IMRT) plans for women with carcinoma of the breast, using a small number of Sim-CT slices, thus avoiding changing the patient's position and potential problems with CT capacity., Materials and Methods: Ten CT scans of women with breast cancer were obtained for use in the study. IMRT plans based on an open tangent pair and additional top-up segment fields were created using the full CT scan, and represented the gold standard treatment plan for comparison purposes. Five-slice CT simulator scans were artificially created by omitting intermediate slices from the full CT scans. Additionally, the intermediate CT slices were recreated via interpolation of the five slices using a standard interpolation algorithm. IMRT plans were created in the same way as for the full CT scans. To allow a suitable plan comparison to be made, the beam segments and monitor units were transferred to the full CT scans, and the dose distribution calculated., Results: The interpolated five-slice plans showed no significant difference in the volume of tissue receiving dose outside the range 95-105%, compared with the IMRT plans created using the full CT data set (1.3 +/- 2.2%, P = 0.092). In contrast, the discrete slice CT simulator plans increased by 6.3 +/- 5.4%, P = 0.0054, showing a statistically significant difference in the dose distribution produced and a clinically inferior plan., Conclusions: Plans created using five discrete slice CT scans were inferior to full CT-derived IMRT treatment plans, and are therefore not acceptable for IMRT. However, interpolating five CT simulator slices provides adequate anatomical information to produce comparable IMRT plans to those created by full CT scans of the patient. This allows the introduction of IMRT for this patient group without the need to change treatment position to accommodate CT scanning.

Local recurrence of cancer in the treated breast following breast-conserving surgery and radiotherapy occurs in a minority of patients, but can represent a significant clinical problem. The impact of local relapse on the subsequent course of the disease is disputed. The aim of this retrospective review was to identify the rate and prognostic factors for breast recurrence and to determine the subsequent outcome. The case notes of 2159 patients treated between 1989 and 1992 were reviewed. Actuarial local relapse rate was 6.3% at 5 years. Factors predictive for recurrence on multivariate analysis were age (P<0.001), status of excision margins (P=0.019), and pathological UICC stage (P=0.01). One hundred and sixty-one patients developed local recurrence in the treated breast of whom 101 were treated with further surgery. The 5-year cancer-specific survival of this group was comparable with that of the patients who remained free of breast relapse (82 vs. 88%) but subsequently fell to 61 vs. 80% at 8 years (P<0.001). Sixty patients were unable to have salvage surgery; their cancer-specific survival was much worse than that of patients with operable recurrences at 33% at 5 years and 13% at 8 years. Eighty-three patients (4% of the original 2159 patients) had uncontrolled local disease at time of death or last follow-up. The prognosis of patients who developed recurrence within 2 years of their initial treatment was inferior to those who developed recurrences after 4 years (cancer-specific survival 5 years post-recurrence 23 vs. 57% P=0.008). Systemic therapy should be considered for patients with early breast recurrence in view of their inferior survival.

Medulloblastoma is an uncommon tumour in the adult population. Maximum surgical resection followed by craniospinal irradiation with a posterior fossa boost is the standard treatment. We report the case history of an adult with medulloblastoma and severe kyphoscoliosis. The unusual anatomy of the patient posed a technical challenge to the oncologist and the physicist in planning the craniospinal radiotherapy. A shaped spinal field matched to a parallel opposed pair of shaped head fields was used. The technique used in treating this patient was made possible with the use of a multileaf collimation and verification with an electronic portal imaging device. The patient remains well with no sign of relapse 4 years after treatment.

At the institute, since the late 1980s, there has been a uniform treatment protocol for the management of the regional lymph nodes in patients referred for radiotherapy following breast-conserving surgery. An analysis of 2,277 consecutive patients referred for radiotherapy between 1989 and 1992, with particular reference to regional lymph node management, has been undertaken. Axillary surgery alone was used in 517 patients (23%); 1,191 (52%) patients had no axillary surgery but had radiotherapy to the axilla, and infraclavicular and supraclavicular fossae by a single anterior field, delivering 40 Gy in 15 daily fractions over 3 weeks; and 474 patients (21%) had axillary surgery followed by radiotherapy. Ninety-five patients (4%) underwent no axillary treatment. There was a total of 155 axillary recurrences with a median follow-up of 5.9 years, giving an actuarial nodal control rate of 94% at 5 years (95% confidence interval (CI) 93.1-95.1). The overall survival at 5 years was 86% (95% CI 84.6-87.5). There was a trend towards improved axillary control with surgery alone compared with radiotherapy alone (4.5% versus 5.9% actuarial axillary failure rate at 5 years). An extremely low incidence of brachial plexus neuropathy secondary to radiotherapy was reported. The multidisciplinary treatment protocol used gave a high rate of regional node control, with minimal recorded morbidity.

The treatment outcomes were reviewed for all the patients at this institute who underwent breast irradiation after breast conserving surgery in 1991. Of a total of 643 patients treated, 194 (30%) had presented with tumours detected by screening mammography. The breast was irradiated with a tangential pair of fields, giving a dose of 40 Gy in 15 fractions over 3 weeks in 97% of these patients. A boost was not used. With a median follow-up of 4.7 years, there was better cancer related survival in patients with screen detected cancers compared with those that were non-screen detected (94% versus 84% at 5 years; P = 0.002). The breast recurrence rate at 5 years was 1% for screen detected cancers compared with 6% for those that were non-screen detected (P = 0.01). Factors additional to screen detected status that were found to be significant for cancer survival were pathological stage (P = 0.03) and histological grade (P = 0.01). In a Cox multivariate analysis, only two factors were significant for breast recurrence: screen detected status (P = 0.023) and histological grade (P = 0.016). This study suggests that breast irradiation with 40 Gy given over 3 weeks after breast conserving surgery for screen detected breast cancer gives a high level of local control out to 5 years.

An audit was performed to assess the frequency of cardiac irradiation in patients receiving radiotherapy for left-sided breast cancer. Images from an 'online' electronic portal imaging device were reviewed in patients who were treated with a tangential pair of megavoltage fields. In 169 consecutive patients treated on a Philips SL25 6 MV linear accelerator equipped with an SRI 100 imaging device, the cardiac apex was included in the radiotherapy field in 15 patients (9%). The long term sequelae of such cardiac irradiation is uncertain. The results of this audit suggest that careful treatment technique and quality control with portal imaging can minimize unnecessary cardiac irradiation in the majority of patients.

In 1990, we published the results of a clinical trial involving 708 patients with breast carcinoma of 4 cm or less in diameter, who, following lumpectomy, were randomized to have radiotherapy to the tumour bed only (limited field, LF group) or to the whole breast and regional nodes (wide field, WF group). No adjuvant systemic therapy was prescribed. At the time the median follow-up was 37 months. We present the updated results after an extended median follow-up of 65 months. The overall survival is 72.7% and 71.2% for the LF and WF groups respectively. The actuarial breast recurrence rate (first event) is 15% (LF) versus 11% (WF) for infiltrating ductal carcinoma, whereas, for infiltrating lobular carcinoma, the recurrence rate was 34% (LF) versus 8% (WF). A high actual recurrence rate of 21% (LF) and 14% (WF) was also found for extensive ductal carcinoma in situ. It was extremely rare for medullary, mucoid or tubular carcinomas to recur. Salvage surgery was possible in 86% (LF) and 90% (WF) respectively. The recurrence rate in the breast following lumpectomy and wide field irradiation is comparable with others reported in the literature. This trial also shows the lumpectomy with limited field irradiation is feasible, albeit with a higher breast recurrence rate; the latter could be reduced by improved selection and refinement of the technique.

Since 1982, the standard method of postmastectomy regional radiotherapy at the Christie Hospital has been to use a single electron field of fixed energy (8 MeV) to irradiate the chest wall, matched to a single megavoltage field (4 or 8 MV) irradiating the nodal areas in the axilla and supraclavicular fossa. (A separate parasternal field was not used.) All 500 cases treated in 1982 and 1983 with this method were reviewed (median follow-up 59 months). Four hundred and twenty-two were referred directly post-mastectomy and 78 for local recurrence after previous mastectomy. Of these, 42 were treated palliatively, and 458 with radical intent. In radical cases the given dose in both fields was 40 Gy in 15 fractions in 3 weeks. The overall survival (n = 458) was 51% (actuarial) at 5 years. At 5 years the local recurrence rate by site and UICC stage were as follows: chest wall - all Stages 17%, Stage I 4%, Stage II 13%, Stage III 26%, recurrent cases 21%; axillary recurrence - all Stages 20%, Stage I 4%, Stage II 10%, Stage III 22%, recurrent cases 39%; supraclavicular recurrences - all Stages 9%. Only one patient of the 500 treated had a parasternal recurrence. Late effects included mild telangiectasia in the electron field and asymptomatic apical lung fibrosis in the photon field. There was no match line fibrosis.

Radiotherapy-induced emesis is poorly controlled with existing antiemetics. 5-Hydroxytryptamine (5HT3) receptor antagonists are a new class of antiemetics which have been demonstrated to be effective in controlling cytotoxic-induced emesis. We have prospectively studied the antiemetic efficacy of the 5HT3 receptor antagonist granisetron in an open non-randomized efficacy and toxicity study, at two dose levels, in patients receiving lower hemibody radiotherapy for multiple bone metastases. Of the 22 patients studied, 13 patients received 20 micrograms/kg and nine patients 40 micrograms/kg of granisetron, administered as an intravenous infusion 1 h before radiotherapy. Radiotherapy was administered as a single exposure to the lower half body to a midline dose of 8 Gy. A complete response (no nausea or vomiting) was observed in 9/13 patients at the lower dose level and 6/9 patients at the higher level. No major adverse events were recorded. We conclude that granisetron is a well-tolerated and effective antiemetic agent in radiotherapy-induced emesis. Formal comparison with conventional antiemetic agents in this situation is required.