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Background and Purpose: Prediction of late normal tissue reactions to radiotherapy would permit tailoring of dosage to each patient. Measurement of residual DNA double strand breaks using pulsed field gel electrophoresis (PFGE) shows promise in this field. The aim of this study was to test the predictive potential of PFGE in a group of retrospectively studied breast cancer patients., Materials and Methods: Thirty nine patients, treated uniformly for breast cancer 9-15 years previously, with excision of the tumour and radiotherapy to the breast and drainage areas, were assessed clinically using the LENT SOMA scale, and a 5-mm punch biopsy taken from the buttock. Fibroblast cell strains were established and used to study residual DNA double strand breaks, using PFGE., Results: There were significant correlations between the DNA assay results and the fibrosis score (r(s) = 0.46; P = 0.003), the combined fibrosis and retraction score (r(s) = 0.45, P = 0.004) and the overall LENT score (r(s) = 0.43; P = 0.006). Using polychotomous logistic regression, the fibroblast DNA assay result was an independent prognostic factor for fibrosis severity., Conclusions: There is a relationship between residual radiation-induced DNA damage in fibroblasts and the severity of the late normal tissue damage seen in the patients from whom the cells were cultured.

Purpose: To study the relationship between the severity of late reactions to radiotherapy in breast cancer patients, and the extent of residual radiation-induced DNA damage, using a rapid assay of keratinocytes obtained directly from skin biopsies., Methods and Materials: A review was made of 32 patients with breast cancer, treated uniformly by radiotherapy between 1983 and 1988, following breast-conserving surgery. Their late radiotherapy reactions were scored (9-14 years post-radiotherapy) using a modified LENT SOMA scale, and a 5-mm buttock skin punch biopsy was obtained. Intact skin was irradiated at room temperature, and after allowing 24 h for repair, the tissue was disaggregated and the cells processed for pulsed field gel electrophoresis (PFGE). Residual DNA damage was expressed as the fraction of DNA released (FDR) following 150 Gy., Results: Studies using flow cytometry on disaggregated breast skin showed that over 90% of the cells were keratinocytes. The PFGE assay was robust with low background FDRs in unirradiated skin samples (mean 3.2%) and a wide range of FDRs following irradiation from 11.5% to 26.6%. No correlation was found between the FDR at 150 Gy (FDR 150) and any of the late reaction scores or retrospective acute reaction scores. There was, however, a borderline significant correlation for family history and FDR 150 (p = 0.059)., Conclusion: Rapid measurement of residual DNA damage in irradiated differentiated keratinocytes, the predominant cell population in skin biopsies, showed no correlation with the severity of symptomatic early or documented late reactions in a retrospectively studied group of 32 breast cancer patients.

The recent amassing of gene expression data to study development in mammals has led to an increased demand for access to human embryological data. The difficulty of obtaining well-preserved human embryos presents an important challenge to studying human development. The Multidimensional Human Embryo project is generating an image data set based on magnetic resonance microscopy of specimens from the highly respected Carnegie Collection of Human Embryos. The data are available from a web site to facilitate the work of clinicians, investigators, and students of human development. A consequence of the project will be to preserve a highly respected, yet impermanent, collection of human embryos and minimize the need for collecting new specimens.

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.

Insulin-like growth factor-I (IGF-I) analogues were produced with the aim of identifying IGF-I residues that contribute to the specificity of binding to the type 1 IGF receptor as opposed to the insulin receptor. Receptor binding properties of a series of A- and B-domain analogues were compared using rat L6 myoblasts, soluble human IGF type 1 receptors and soluble human insulin receptor isoforms HIR-A (-Ex11) and HIR-B (+Ex11). IGF-I analogues, [Leu8] IGF-I and [Phe59] IGF-I, were shown to exhibit respectively, a 28- and 17-fold decrease in affinity for the HIR-A with only a 6- and 5-fold decrease in affinity for the human IGF type 1 receptor. In contrast, the analogue [His4] IGF-I was equipotent to IGF-I in binding to the soluble type 1 IGF receptor while showing 7-fold and 4-fold increases in HIR-A and HIR-B binding respectively. Furthermore, [Leu62] IGF-I was 8-fold less potent than IGF-I in soluble IGF type 1 receptor binding but only showed a 2-fold decrease in HIR-A and HIR-B binding. Our study supports the conclusion that the co-evolution of the IGF-I and insulin receptor/ligand systems has resulted in subtle structural differences in the A- and B-regions of each ligand important for defining receptor binding specificity.

Prognostic factors predicting for breast recurrence following breast conserving surgery and radiotherapy have been identified in a prospective randomised trial comparing two different radiotherapy techniques. The first used megavoltage radiation to encompass the whole breast and regional nodes (WF group). The second used an electron field directed to the tumour bed only (LF group). With a median follow up of 8 years survival in both groups was the same (72%). There was an increased rate of breast recurrence in the LF group: 25%, compared to the WF group: 13% (P = 0.00008), expressed in actuarial terms at 8 years. In a multivariate analysis of factors predicting for breast recurrence, once the difference in treatment technique is allowed for, only two factors were found to be significant: histological grade (P = 0.013) and lymphovascular invasion in the histological specimen (P = 0.037).

Candida albicans produces large amounts of the acyclic pentitol D-arabitol in culture and in infected animals and humans, and most strains also grow on minimal D-arabitol medium. An earlier study showed that the major metabolic precursor of D-arabitol in C. albicans was D-ribulose-5-PO4 from the pentose pathway, that C. albicans contained an NAD-dependent D-arabitol dehydrogenase (ArDH), and that the ArDH structural gene (ARD) encoded a 31-kDa short-chain dehydrogenase that catalyzed the reaction D-arabitol + NAD <=> D-ribulose + NADH. In the present study, we disrupted both ARD chromosomal alleles in C. albicans and analyzed the resulting mutants. The ard null mutation was verified by Southern hybridization, and the null mutant's inability to produce ArDH was verified by Western immunoblotting. The ard null mutant grew well on minimal glucose medium, but it was unable to grow on minimal D-arabitol or D-arabinose medium. Thus, ArDH catalyzes the first step in D-arabitol utilization and a necessary intermediate step in D-arabinose utilization. Unexpectedly, the ard null mutant synthesized D-arabitol from glucose. Moreover, 13C nuclear magnetic resonance studies showed that the ard null mutant and its wild-type parent synthesized D-arabitol via the same pathway. These results imply that C. albicans synthesizes and utilizes D-arabitol via separate metabolic pathways, which was not previously suspected for fungi.

An audit was carried out of post-operative radiotherapy given for carcinoma of the endometrium at the Christie Hospital between the years of 1984-86. 139 patients were treated following total abdominal hysterectomy (TAH) and bilateral salpingo-oophorectomy (BSO). 54 patients were treated with vaginal brachytherapy alone, 55 had pelvic brick external beam irradiation and 30 patients had both external beam irradiation and vaginal brachytherapy. Overall survival was 84% at 5 years, with a 5.8% local recurrence rate. Histological grade was a prognostic factor for survival (p=0.023) and relapse (p=0.002). Tumour stage was a significant prognostic factor for survival (p=0.011), but not relapse. Survival for stage IB disease was 100% at 5 years with no local recurrence. Major treatment related morbidity was 1.4%, overall; for vaginal brachytherapy alone 0%; for external beam therapy 2%; and combined therapy 3%. Given their good prognosis, and the small but definite risk of major morbidity, patients with stage IB disease may not need postoperative external beam irradiation.

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.

Between 1979 and 1984 thirty-seven patients were treated with combination chemotherapy for metastatic seminoma; 27 of these had relapsed following initial radiotherapy for stage I and IIA disease and 10 patients with stage IIB-IV disease received chemotherapy de novo followed by radiotherapy to sites of bulk disease. Treatment consisted of either a cis-platinum containing combination (25 patients), or cyclophosphamide and etoposide (12 patients). The overall survival of all patients at 5 years was 49%, 34 patients were assessable for response; a CR was obtained in 8 (24%) and a GPR in 19 (56%), the 5 year survival of this group being 66% at 5 years. No difference in survival was seen in relation to age, previous irradiation, serum HCG or LDH; bulk disease however, was an adverse prognostic factor. Survival was similar for both chemotherapy schedules but neutropenia and life-threatening sepsis was less with the cyclophosphamide etoposide combination.

A patient presented with mild hyperthyroidism, elevated serum T4 and T3, and an inappropriately raised serum thyrotrophin (TSH). There was no evidence of pituitary tumour (alpha-subunit secretion and CT scan of the pituitary were normal). The TSH response to TRH was greater than normal. The elevated TSH was suppressed by oral triiodothyronine (100 micrograms daily for 10 d). The normal diurnal variation of TSH was preserved. Intravenous injection of the dopamine receptor blocking agent domperidone led to a greater than normal elevation in TSH (maximum increments 18-20 mU/l). This increased dopaminergic tone was similar in studies carried out in the morning and late evening. The dopamine agonist bromocriptine (2.5 mg twice daily) failed to suppress serum TSH either acutely or over 6 weeks. The circadian rhythm was unaltered by this treatment. Basal serum prolactin levels were normal, and responded appropriately to TRH, domperidone and bromocriptine. These observations indicate that dopamine does not control the diurnal variation of TSH in nontumoral TSH-mediated hyperthyroidism. The increased dopaminergic tone demonstrated may be secondary to the primary failure of pituitary-thyroid feedback in the condition.