Alison L. Jones

The Royal Marsden Hospital pilot tamoxifen chemoprevention trial

A pilot randomised placebo controlled trial using tamoxifen in healthy women at increased risk of developing breast cancer, has been undertaken in order to evaluate the problems of accrual, acute symptomatic toxicity, compliance, and safety as a basis for subsequent large national multicentre trials designed to test whether tamoxifen can chemoprevent breast cancer.From October 1986 until June 1993, 2012 healthy women with an increased risk of developing breast cancer, usually because of a strong family history, were randomly allocated to receive tamoxifen 20 mgs/day or placebo for up to 8 years if possible.Accrual remained high in spite of extensive informed consent regarding potential risk. Acute symptomatic toxicity was low for participants on tamoxifen or placebo and compliance remained correspondingly high with a predicted 77% of women on tamoxifen and 82% of women on placebo continuing medication at 5 years. There was a significant increase in hot flushes (34% versus 20%) mostly in premenopausal women (p < 0.005), vaginal discharge (16% versus 4%, p < 0.005), and menstrual irregularities (14% versus 9%, p < 0.005). The requirements for hormone replacement therapy for women on tamoxifen or placebo were the same.Safety monitoring indicates no adverse anti oestrogenic effects of tamoxifen. There was no obvious effect of tamoxifen on bone mineral densities (single photon radial absorption). The fibrinogen and antithrombin III were both lowered, resulting in no observed detrimental effect on the ratio of these clotting factors. There was a significant reduction in the serum cholesterol maintained out to 5 years. Annual pelvic assessment using transvaginal ultrasound indicates an increased incidence of uterine fibromata and benign ovarian cysts. These results have encouraged the commencement of the NSABP national trial in the USA, and the subsequent start of national trials in Italy and the UK, which together should provide sufficient evidence to evaluate the efficacy of tamoxifen for prevention of breast cancer.

The influence of aminoglutethimide and its analogue rogletimide on peripheral aromatisation in breast cancer.

The influence of the prototype aromatase inhibitor Aminoglutethimide (AG) and its analogue Rogletimide (RG) on peripheral aromatisation were investigated in 13 postmenopausal women with advanced breast cancer. Seven patients received AG 1,000 mg daily plus Hydrocortisone (HC) cover and six received RG as dose escalation of 200 mg bd, 400 mg bd and 800 mg bd. In vivo aromatase inhibition was investigated using the double bolus injection technique with [4-14C] oestrone ([4-14C]E1) and [6,7-3H] androstenedione ([6,7-3H]4A) followed by a 96 h urine collection. The labelled urinary oestrogens were separated and purified by chromatography and HPLC. Plasma oestradiol (E2) was also measured. AG mean aromatase inhibition was 90.6% +/- 1.8 s.e.m. and E2 suppression 75.7% +/- 7.3 s.e.m. RG mean aromatase inhibition was 50.6% +/- 9.8 s.e.m. at 200 mg bd, 63.5% +/- 5.7 s.e.m. at 400 mg bd and 73.8% +/- 5.8 s.e.m. at 800 mg bd. E2 suppression was 30.7% +/- 9.5 s.e.m., 40.2% +/- 10.3 s.e.m. and 57.6% +/- 9.2 s.e.m. respectively. These results confirm the efficacy of AG as an aromatase inhibitor. RG produced dose dependent E2 suppression and aromatase inhibition, but even at the maximum tolerated dose of 800 mg bd had sub-optimal aromatase inhibition and oestradiol suppression compared with AG.

Primary medical (neo-adjuvant) chemotherapy for operable breast cancer

84 patients with large operable breast cancer have been treated with primary medical chemotherapy rather than mastectomy in three sequential studies. 86% had tumours greater than 4 cm in diameter; median diameter was 6 cm (range 1-12). Median age was 46 years (range 23-66). In the first two studies 64 patients were treated with either CMF [cyclophosphamide 100 mg orally days 1-14, methotrexate 50 mg intravenously (i.v.) days 1 and 8, and 5-fluorouracil 1 g i.v. days 1 and 8, repeating at 28-day intervals for six courses] or MMM (mitozantrone 8 mg/m2 i.v. once every 3 weeks, methotrexate 50 mg i.v. once every 3 weeks, mitomycin C 8 mg/m2 once every 6 weeks, for 8 courses). 69% achieved an overall response including 17% complete remissions. 27% have had local relapse but only 3% uncontrolled local relapse. Only 14% have required mastectomy. In the third study which is ongoing, 19 patients have been treated with infusional FEC (5-fluorouracil 200 mg/m2 i.v. 24 hourly by continuous infusion via a Hickman line for 6 months, epirubicin 50 mg/m2 i.v. bolus once every 3 weeks for 6 months, cisplatin 60 mg/m2 i.v. once every 3 weeks for 6 months with appropriate intravenous hydration). Overall response rate so far is 84% with 58% complete remissions. There have been no local relapses and no patient has required mastectomy. This study demonstrates that primary medical chemotherapy can be used to avoid mastectomy in the great majority of patients presenting with large operable primary breast cancer. Infusional FEC may be more active than conventional chemotherapy in terms of overall response and complete remission rate, and infusional FEC chemotherapy now needs to be compared with conventional chemotherapy. The concept of primary medical therapy should also be compared with conventional mastectomy followed by adjuvant chemotherapy.

The influence of intramuscular 4-hydroxyandrostenedione on peripheral aromatisation in breast cancer patients

The influence of the aromatase inhibitor 4-hydroxyandrostenedione (4OHA) given intramuscularly on the peripheral aromatisation of androstenedione into oestrone was investigated in postmenopausal women with breast cancer and compared with the suppression of plasma oestradiol (E2). 7 patients were investigated before and during treatment on day 7, i.e. midway between two weekly injections. After an intravenous injection of [3H] androstenedione and [14C] oestrone, urine was collected for 96 h and the isotope ratio determined in the urinary oestrogen metabolites after isolation with high performance liquid chromatography. At 250 mg, 4OHA inhibited aromatisation to [mean (S.D.)] 15.2 (5)% of baseline (P < 0.002). There was significantly greater inhibition to 8.1 (2.7)% at 4OHA 500 mg (P < 0.01). Plasma E2 was reduced to 41.2 (14.1)% of baseline at 4OHA 250 mg with a further reduction to 32.7 (19.8)% at 500 mg (P < 0.05). These results confirm the dose-response relation previously established with plasma oestrogen measurements alone.

THE INFLUENCE OF CGS 16949A ON PERIPHERAL AROMATISATION IN BREAST CANCER PATIENTS

The influence of a new aromatase inhibitor, CGS 16949A on peripheral aromatisation of androstenedione into oestrone was investigated in postmenopausal women with breast cancer. A mixture of 3H androstenedione and 14C oestrone was injected, and all urine was collected for the following 96 h. The isotope ratio was determined in the urinary oestrogen metabolites after isolation by HPLC. Eight patients were investigated before and during treatment with CGS 16949A. At a dose of 1 mg b.d. (eight patients) CGS 16949A inhibited aromatisation by a mean value of 82.4% (range 71.3 to 93.7%). When the drug dose was escalated to 2 mg b.d. (three patients) aromatisation was inhibited by a mean of 92.6% (range 90.6 to 95.8%), these results suggest that CGS 16949A at a dose of 1 mg b.d. causes submaximal aromatase inhibition in many patients, while a dose of 2 mg b.d. seems to result in greater than 90% aromatase inhibition. These data are consistent with previous observations that the higher dose is more effective in suppression of plasma oestradiol levels.

Haemostatic changes and thromboembolic risk during tamoxifen therapy in normal women

Tamoxifen has been implicated as a risk factor for venous thrombosis in advanced breast cancer although the evidence for increased arterial or venous thrombosis with tamoxifen in early breast cancer is less clear. The effect of tamoxifen on haemostasis, and thereby possible thromboembolic risk, was investigated in normal women enrolled in a placebo controlled trial of tamoxifen as a chemopreventative agent for breast cancer. There was an initial reduction in fibrinogen levels in all women on tamoxifen over the first year of follow-up and a marginal reduction in antithrombin III and Protein S in postmenopausal women at 6 months. There were no changes in cross linked fibrinogen degradation products or Protein C for pre or post-menopausal women. There was no increase in the incidence of thromboembolic events on tamoxifen. This study demonstrates that tamoxifen has only marginal effects on factors involved in haemostasis reported to affect the incidence of arterial or venous thromboembolic disease. The follow-up time is relatively short (maximum 36 months) and careful long term follow-up is necessary to detect clinically significant morbidity.

A randomised trial comparing combination chemotherapy using mitomycin C, mitozantrone and methotrexate (3M) with vincristine, anthracycline and cyclophosphamide (VAC) in advanced breast cancer

This paper describes a randomised clinical trial in patients with advanced breast cancer, comparing the regimen 3M, mitomycin C 7-8 mg m-2 (day 1), mitozantrone 7-8 mg m-2 (day 1 and 21), methotrexate 35 mg m-2 (day 1 and 21) given on a 42 day cycle with a standard anthracycline containing regimen, VAC, vincristine 1.4 mg m-2 (day 1), anthracycline (adriamycin or epirubicin) 30 mg m-2 (day 1), cyclophosphamide 400 mg m-2 (day 1) given on a 21 day cycle. Of a total of 217 patients, 107 were randomised to 3M and 110 to VAC and a mean of 5.5 courses was given per patient. The overall response rate (complete and partial) was 53% (95% Confidence Limits (CL): 43-62%) for 3M and 49% (CL; 39-58%) for VAC. The response according to sites of metastases was the same for both treatment groups. Symptomatic toxicity including alopecia, neuropathy, vomiting (P less than 0.001) and nausea (P less than 0.01) were significantly less for 3M. Myelosuppression including leucopenia (P less than 0.001) and thrombocytopenia (P less than 0.001) was significantly greater with 3M at day 21, although there was no difference in nadir counts in patients at special risk of myelosuppression and there was no evidence of an increase in infective or bleeding complications. There was no significant difference in the duration of response to 3M (10 months, CL 6-15) and VAC (11 months, CL 7-12), nor in survival (3M, 8 months, CL 6-12; VAC, 10 months, CL 8-12). These results indicate that 3M is as effective as, but has significantly less symptomatic toxicity than, an anthracycline containing regimen for the treatment of advanced breast cancer.

Influence of aminoglutethimide on plasma oestrogen levels in breast cancer patients on 4-hydroxyandrostenedione treatment

SummaryThe clinical and biochemical effects of combined treatment with the two aromatase inhibitors aminoglutethimide and 4-hydroxyandrostenedione were evaluated in 10 patients suffering from advanced breast cancer. All patients had become resistant to treatment with one of the drugs before having combined treatment. Seven patients progressing on 4-hydroxyandrostenedione who had aminoglutethimide added to their treatment and achieved a further suppression of plasma oestradiol by a mean of 40.0% (p<0.05). Plasma oestrone was suppressed by a mean of 40.6% (p<0.025) and plasma oestrone sulphate was suppressed by a mean of 63.6% (p<0.025). Two of the patients, neither of whom had responded to 4-hydroxyandrostenedione alone, experienced objective tumour regression when aminoglutethimide was given in concert. Three patients progressing on aminoglutethimide who had 4-hydroxyandrostenedione added showed no further suppression of their plasma oestrogen levels, and no tumour regression was observed. These findings suggest a dose-response relationship between plasma oestrogen suppression at low postmenopausal levels and objective tumour response in breast cancer.

The budgetary impact of 5-HT3 receptor antagonists in the management of chemotherapy-induced emesis

The study examined the budgetary implications of using 5-hydroxytryptamine3 receptor antagonists (5-HT3RA), granisetron or ondansetron, in the management of chemotherapy-induced emesis (CIE). A treatment model was constructed to represent a baseline of efficacy and costs for treating a cohort of patients with conventional antiemetics. Groups of patients who would be expected to receive the most benefit from 5-HT3RA were then identified and the effect upon costs of using these compounds in a consecutively larger proportion of selected patients was calculated. On the basis of illustrative costs from The Cookridge Hospital in the UK, it was concluded that the new antiemetics can be used in acute emesis with substantial clinical benefit for an increase of 3-10% to total treatment costs. However, for delayed emesis these compounds have not yet shown a clinical advantage, and the increase in total costs of 12-34% is not justified.

6 Growth factors in haemopoiesis

Summary Haemopoietic growth factors have for over two decades allowed experimentalists to grow haemopoietic bone marrow cells in vitro. With refinements in technique and the discovery of novel growth factors, all of the known haemopoietic lineages can now be grown in vitro. This has allowed a much greater understanding of the complex process of haemopoiesis from the haemopoietic stem cell to the mature, functioning end-cell. The in vivo action of these growth factors has been harder to investigate. Although recombinant technology has afforded us the much greater quantities necessary for in vivo work, problems remain with administration because of effects on other tissues. Interpretation of results is difficult because of the complex inter-relationships which exist between factors. Some of these have been defined in vitro and it appears likely that they also operate in vivo. Erythropoietin is a physiological regulator of erythropoiesis. It has been detected in vivo with levels responding appropriately to stress (i.e. elevated in anaemia) and, when administered in pharmacological doses, has been shown to correct anaemia. Granulocyte/macrophage colony-stimulating factor (GM-CSF) has been detected in vivo and may influence the production and function of granulocytes and macrophages, although how it is regulated is unknown. Granulocyte colony-stimulating factor (G-CSF) and macrophage colony-stimulating factor are more lineage-specific. Interleukin 3 (IL-3), although it has not been detected in vivo, may act on a primitive marrow precursor by expanding the population and making these cells more susceptible to other growth factors, such as GM-CSF. Interleukin 1 (IL-1) has been detected in vivo, does not appear to have any isolated action on bone marrow (except possibly radioprotection) but probably acts synergistically with other growth factors, such as G-CSF. Interleukins 2, 4, 5 and 6 have not been detected in vivo. All have effects on B-cells. In addition IL-2 is an essential factor for the in vitro growth of T-cells and may have antitumour effects in vivo. IL-5 is an eosinophil growth factor in vitro. Megakaryocytopoiesis is also affected by humoral factors. Factors, alone or in combination, may be useful to restore functional granulopoiesis when used therapeutically. Some can be used as anticancer agents, although there may be a risk of induction of haematological malignancy. Increased understanding of their physiological roles will allow a more rational use.