Prognostic factors in 1,038 women with metastatic breast cancer

BACKGROUND

Treatment of metastatic breast cancer (MBC) remains palliative. Patients with MBC represent a heterogeneous group whose prognosis and outcome may be dependent on host factors. The purpose of the present study was dual: first, to draw up a list of factors easily available in everyday clinical practice requiring no sophisticated or costly methods and second, to provide results from a large cohort of women who underwent diagnostic and treatment at a single institution.

PATIENTS AND METHODS

From 1975 to 2005, a total of 1,038 women with MBC during their follow-up were included in this retrospective analysis. Patients were subsequently assigned to five groups according to the period of metastatic diagnosis.

RESULTS

It is shown that age at initial diagnosis, hormonal receptor status and site of metastasis are the most relevant prognostic factors for predicting survival from the time of metastastic occurrence. It is also shown that a metastasis-free interval is an easily and immediately available multifactorial prognostic index reflecting the multiparametric variability of the disease.

CONCLUSION

These fundamental observations may assist physicians in evaluating the survival potential of patients and in directing them toward the appropriate therapeutic decision.

Early versus late local recurrences after conservative treatment of breast carcinoma: differences in primary tumor characteristics and patient outcome

OBJECTIVES

To investigate whether some aspects of patient or tumor characteristics influence the timing of local recurrence (LR) in breast cancer treated conservatively, and to assess the impact of the timing of LR on patient outcome.

METHODS

A retrospective analysis was conducted on patients treated with conservative breast surgery followed by radiotherapy for breast carcinoma who developed LR. Out of 2,008 cases treated in our Institute between 1977 and 2002, 180 ipsilateral LR were observed. Of these, 46 LR were observed within 36 months after treatment, called early local recurrence (ELR), 44 developed between 37 and 60 months, called medium local recurrence (MLR), and 90 occurred after 60 months, called late local recurrence (LLR). Patient and tumor characteristics were analyzed in the 2 groups and compared.

RESULTS

Primary tumors >20 mm were more frequently found in patients with ELR (31%) than in patients with LLR (17%, p = 0.047). Grade 3 tumors were more often encountered in patients with ELR than in patients with LLR (27 versus 7%, p = 0.0002). Patients with ELR more frequently had tumors with negative estrogen receptors than patients with LLR (37% versus 6%, p < 0.0001). There was no statistically significant difference in the axillary lymph node (LN) status between patients with ELR and those with LLR (35 and 23% of positive LN, respectively, p = 0.24). Tumor size, grade, LN status, hormone receptors and the timing of LR affected the specific survival (SS) from initial surgery. On multivariate analysis, only LN status and the timing of LR retained an independent prognostic value, with an odds ratio of 6.7 for ELR. After LR, the SS was also influenced by all of the above factors, and on multivariate analysis, LN status, hormone receptors and the timing of LR were independent predictors with an odds ratio of SS of 2.50 in case of ELR (p = 0.006). The 5-year SS after LR for ELR, MLR and LLR were 55.8, 74.8 and 79.5%, respectively.

CONCLUSIONS

Unfavorable tumor characteristics such as big size, high grade, lack of hormone receptors, but not LN status, were associated with ELR. These findings suggest that patients with such aggressive tumor characteristics who do not recur early will have a lower risk of LLR than patients with more favorable factors.

EORTC guidelines for the use of erythropoietic proteins in anaemic patients with cancer: 2006 update

Anaemia is frequently diagnosed in patients with cancer, and may have a detrimental effect on quality of life (QoL). We previously conducted a systematic literature review (1996-2003) to produce evidence-based guidelines on the use of erythropoietic proteins in anaemic patients with cancer.[Bokemeyer C, Aapro MS, Courdi A, et al. EORTC guidelines for the use of erythropoietic proteins in anaemic patients with cancer. Eur J Cancer 2004;40:2201-2216.] We report here an update to these guidelines, including literature published through to November 2005. The results of this updated systematic literature review have enabled us to refine our guidelines based on the full body of data currently available. Level I evidence exists for a positive impact of erythropoietic proteins on haemoglobin (Hb) levels when administered to patients with chemotherapy-induced anaemia or anaemia of chronic disease, when used to prevent cancer anaemia, and in patients undergoing cancer surgery. The addition of further Level I studies confirms our recommendation that in cancer patients receiving chemotherapy and/or radiotherapy, treatment with erythropoietic proteins should be initiated at a Hb level of 9-11 g/dL based on anaemia-related symptoms rather than a fixed Hb concentration. Early intervention with erythropoietic proteins may be considered in asymptomatic anaemic patients with Hb levels 11.9 g/dL provided that individual factors like intensity and expected duration of chemotherapy are considered. Patients whose Hb level is below 9 g/dL should primarily be evaluated for need of transfusions potentially followed by the application of erythropoietic proteins. We do not recommend the prophylactic use of erythropoietic proteins to prevent anaemia in patients undergoing chemotherapy or radiotherapy who have normal Hb levels at the start of treatment, as the literature has not shown a benefit with this approach. The addition of further supporting studies confirms our recommendation that the target Hb concentration following treatment with erythropoietic proteins should be 12-13 g/dL. Once this level is achieved, maintenance doses should be titrated individually. There is Level I evidence that dosing of erythropoietic proteins less frequently than three times per week is efficacious when used to treat chemotherapy-induced anaemia or prevent cancer anaemia, with studies supporting the use of epoetin alfa and epoetin beta weekly and darbepoetin alfa given every week or every 3 weeks. We do not recommend the use of higher than standard initial doses of erythropoietic proteins with the aim of producing higher haematological responses, due to the limited body of evidence available. There is Level I evidence that, within reasonable limits of body weight, fixed doses of erythropoietic proteins can be used to treat patients with chemotherapy-induced anaemia. This analysis confirms that there are no baseline predictive factors of response to erythropoietic proteins that can be routinely used in clinical practice if functional iron deficiency or vitamin deficiency is ruled out; a low serum erythropoietin (EPO) level (only in haematological malignancies) appears to be the only predictive factor to be verified in Level I studies. Further studies are needed to investigate the value of hepcidin, c-reactive protein, and other measures as predictive factors. In these updated guidelines, we explored a new question of whether oral or intravenous iron supplementation increases the response rate to erythropoietic proteins. We found no evidence of increased response with the addition of oral iron supplementation, but there is Level II evidence of improved response to erythropoietic proteins with the addition of intravenous iron. However, the doses and schedules for intravenous iron supplementation are not yet well defined, and further studies in this area are warranted. The two major goals of erythropoietic protein therapy are prevention or elimination of transfusions and improvement of QoL. The total body of evidence shows that red blood cell (RBC) transfusion requirements are reduced following treatment with erythropoietic proteins. This analysis also confirms that QoL is significantly improved in patients with chemotherapy-induced anaemia and in those with anaemia of chronic disease following erythropoietic protein therapy, with more robust evidence now available that QoL was improved in studies investigating early intervention in cases of chemotherapy- or radiotherapy-induced anaemia. There is only indirect evidence that patients with chemotherapy-induced anaemia or anaemia of chronic disease initially classified as non-responders to standard doses proceed to respond to treatment following a dose increase. None of the studies addressed the question in a prospective, randomised fashion, and so the Taskforce does not recommend dose escalation as a general approach in all patients who are not responding. There is still insufficient data to determine the effect on survival following treatment with erythropoietic proteins in conjunction with chemotherapy or radiotherapy. Our analysis of survival endpoints in studies involving patients receiving radio(chemo)therapy found that most studies were inconclusive, with no clear link between the use of erythropoietic proteins and survival. Likewise, we found no clear link between erythropoietic therapy and other endpoints such as local tumour control, time to progression, and progression-free survival. There is no evidence that pure red cell aplasia occurs in cancer patients following treatment with erythropoietic proteins, and the fear of this condition developing should not lead to erythropoietic proteins being withheld in patients with cancer. There is Level I evidence that the risk of thromboembolic events and hypertension are slightly elevated in patients with chemotherapy-induced anaemia receiving erythropoietic proteins. Additional trials are warranted, especially to define the optimal doses and schedules of intravenous iron supplementation during erythropoietic therapy. While our review did not address cost benefit evaluations in detail, the consensus is that studies taking into account all real determinants of cost and benefit need to be performed prospectively.

Clinical significance of brain metastases occurrence in HER2 overexpressing metastatic breast cancer patients treated with trastuzumab

10593

Background: Recent data report that HER2 overexpressing metastatic breast cancer patients (HER+ MBC pts) treated with trastuzumab (T) have a high rate of Brain metastasis (BM). This study aimed to evaluate the prognostic significance of BM occurrence and the related clinical outcome in a specific patient population. Methods: All the HER+MBC patients treated with trastuzumab (with or without chemotherapy) between 09/1999 and 12/2004 were included in this study. Results: A total of forty three patients were enrolled into the study cohort. The median follow-up was 48 months (range, 11–166). Fifteen patients (35%) developped BM. The median interval from the the first MBC event to BM was 18 months (range, 1–65). In multivariate analysis; younger age was the only factor associated with BM occurrence (46 versus 57 years; p = 0.01). Patients with BM tend to have a longer median duration of response to T than patients without BM (16 months versus 13 months; p = 0.1). At the time of BM appearance, 6 of the 15 patients (40%) were still responding or had achieved extracranial stable disease while receiving trastuzumab. Twelve out of 15 (80%) pts received a whole-brain radiation therapy, and 8 pts continued to receive trastuzumab until extracranial disease progression. The median overall survival for patients diagnosed with BM was 10 months (range, 2–42). At three-year, there was no significant difference in overall survival rates between the two groups. The 3-YS was 63.5% and 66.7% for pts with or without BM, respectively; (p = 0.7). Conclusions: The BM occurrence in HER2+ MBC pts treated with Trastuzumab is not linked to tumour resistance, but likely related to the T inability to cross the blood-brain barrier. There is no impaired survival for these pts treated with effective and appropriate therapy.

[Table: see text]

EORTC guidelines for the use of erythropoietic proteins in anaemic patients with cancer

Anaemia is frequently diagnosed in patients with cancer, yet it is difficult to identify a single cause due to its multifactorial aetiology. We conducted a systematic literature review (1996-2003) to produce evidence-based guidelines on the use of erythropoietic proteins in anaemic patients with cancer (see ). Level I evidence exists for a positive impact of erythropoietic proteins on haemoglobin (Hb) levels when administered to patients with chemotherapy-induced anaemia or anaemia of chronic disease, when used to prevent cancer anaemia, in patients undergoing cancer surgery and following allogeneic bone marrow transplantation. The Hb level at which erythropoietic protein therapy should be initiated is difficult to determine as it varied between studies; a large number of Level I studies in patients with chemotherapy-induced anaemia or anaemia of chronic disease enrolled patients with a Hb concentration </=105 g/L, but none compared the effect of different baseline Hb levels on the response to treatment. Similarly, several studies defined the target Hb concentration as 120-130 g/L following treatment with erythropoietic proteins, but none specifically addressed the correlation between target Hb level and clinical benefit in a randomised fashion. Level I evidence shows that red blood cell (RBC) transfusion requirements are significantly reduced with erythropoietic protein therapy in patients with chemotherapy-induced anaemia or when used to prevent cancer anaemia (approximately 20% reduction compared with controls). We found indirect Level I and III evidence that patients with chemotherapy-induced anaemia or anaemia of chronic disease initially classified as non-responders to standard doses proceed to respond to treatment following a dose increase (absolute increases in response rate ranged from 8% to 18%). However, none of these studies examined the effect on response rates of a longer treatment period at the lower dose, or performed a randomised comparison of a dose increase versus an unchanged dose. There is Level I evidence to show that quality-of-life (QOL) is significantly improved in patients with chemotherapy-induced anaemia and in those with anaemia of chronic disease, particularly in patients achieving a Hb response to erythropoietic protein therapy. There are insufficient data to determine the effect on survival following treatment with erythropoietic proteins in conjunction with chemotherapy or radiotherapy. There is Level I evidence that dosing of erythropoietic proteins less frequently than three times per week (TIW) is efficacious when used to treat chemotherapy-induced anaemia or prevent cancer anaemia. There is Level III evidence that initial doses of erythropoietic proteins considered to be higher than current standard practice produce higher haematological responses in patients with chemotherapy-induced anaemia or anaemia of chronic disease. Level I evidence demonstrates that several baseline patient parameters (e.g., low endogenous erythropoietin [EPO] concentration, age <60 years, Hb concentration >/=90 g/L) impact upon the response to erythropoietic proteins when used to treat chemotherapy-induced anaemia or prevent cancer anaemia. Evidence indicates that endogenous EPO concentration impacts on response in patients with lymphoproliferative malignancies, but is not a valid parameter in patients with solid tumours. There is Level I evidence that fixed doses of erythropoietic proteins can be used at the start of therapy to treat patients with chemotherapy-induced anaemia, but maintenance doses should be titrated individually. There is no evidence that pure red cell aplasia (PRCA) occurs following treatment with erythropoietic proteins in patients with chemotherapy-induced anaemia or when used prophylactically in patients with cancer. There is Level I evidence that the risk of thromboembolic events and hypertension are slightly elevated in patients with chemotherapy-induced anaemia receiving erythropoietic proteins. Level I evidence supports the effectiveness of erythropoietic proteins to prevenroteins to prevent anaemia in non-anaemic cancer patients receiving chemotherapy or radiotherapy or in those undergoing cancer surgery. However, these are non-licensed indications and we do not currently recommend the prophylactic use of erythropoietic proteins to prevent anaemia in patients who have normal Hb values at the start of treatment. Additional trials are warranted, especially on the issues of iron replacement and cost-effectiveness of erythropoietic protein therapy, as well as on tumour response/progression and survival.

Chimiothérapie néoadjuvante dans les astrocytomes fibrillaires de grade II symptomatiques non opérables de l’adulte

We collected 6 case-reports of symptomatric non removable low grade fibrillary astrocytoma of adults treated with a procarbazine-CCNU-vincristine chemotherapy regimen. All patients had drug-resistant epilepsy but brain imaging was stable. Total gross resection was rejected because of Volume or tumor location. After 4 to 7 cycles of chemotherapy, 2 patients had partial response and one minor response on brain MRI. All of them were seizure-free. Progression free survival was not reached at 5 Years. Up-front chemotherapy for low-grade astrocytomas may be useful and has to be prospectively evaluated.

Prognostic value of S-phase fraction in 920 breast cancer patients: focus on T1N0 status

The aim of this study was to reexamine the prognostic role of tumor cell kinetics measured by S-phase fraction (SPF) and to establish its clinically relevant threshold values. SPF was determined by flow cytometry in a group of 920 consecutive breast cancer patients, all followed at our institute for 10 years (1988 to 1998). Mean age was 60.5 years (27-89 years). Median follow-up was 63 months (3-150 months). All patients had initial surgical treatment. SPF quartiles were: Q1=3.08%, median value = 5.98%, Q3=10.22%. A significant difference in overall specific survival was obtained between two populations divided by a cutoff at Q1 (p < 0.0001). A multifactorial analysis including SPF and known prognostic factors such as tumor size, node status, histological grade, ER and PR status was performed using the Cox model in a population of 719 patients: univariate analysis showed that each of these factors had significant influence on overall survival. Multivariate analysis selected three of them, ranked by decreasing order of hazard ratio (HR) value: SPF (HR: 3.88, p < 0.001), tumor size (HR: 2.49, p < 0.001) and nodal status (HR: 2.28, p < 0.001). In addition, when tumors were stratified according to SPF quartile values, there were statistically different overall survival curves in patients with small tumors (< 2 cm) and in axillary node-negative patients.

Breast Cancer in Elderly Women: is Partial Breast Irradiation a Good Alternative?

BACKGROUND

Approximately half of all breast cancer occurs after age 65. Several aspects for the treatment of early breast cancer may be influenced by patient age, including postoperative radiation therapy (RT), in order to prevent the risk of local recurrence (LR). Postoperative adjuvant RT, improving the chances of local control, is not always completed because of comorbidity-associated factors. Does an alternative exist between a 5-week radiotherapy regime and no irradiation after breast conservative surgery without burdening the overall therapeutic management?

METHODS

The authors review the literature regarding age-specific issues in the irradiation of breast cancer and the potential role of a partial breast irradiation (PBI) to prevent LR in the ipsilateral breast.

RESULTS

Phase II and III trials have been analyzed for feasibility, efficacy and toxicity. PBI may be delivered with low or high dose rate brachytherapy and intra operative, or external beam radiation therapy. PBI satisfies the control quality criteria. The majority of the teams provide PBI recurrence rates lower than 5% (0-4.4%) with a median follow-up varying between 8 and 72 months, associated with cosmetic results comparable to those achieved with conventional external beam.

CONCLUSIONS

Breast cancer in elderly women represents a medical and economical problem. The recommended conservative treatment includes RT for 50 Gy over 5 weeks. Some subgroups of patients did not receive radiotherapy because of comorbidity-associated factors or more favorable tumor biology. PBI seems to be an acceptable alternative to adjuvant RT over 5 weeks and no irradiation. The evaluation of toxicity and efficacy, especially in terms of local control, is necessary and large multicentric phase III trials comparing the two irradiation approaches are needed, including quality of life, economic considerations and longer follow-up.

Radio-prevention of micrometastases

In developed countries, the cancer incidence is about 150,000 cases per year and half of people with cancer may die from the extension of the primary tumour in secondary deposits. This disaster costs more than 2 billion euro per year. People with cancer are often treated with surgery and/or radiotherapy of localized primary tumour and chemo-prevention of occult disseminated micrometastases. Since chemotherapy essentially targets cycling tumour cells, quiescent micrometastases which may contain only one cell may escape. We previously reported that human melanoma clones with high metastatic potential and low gangliosides content appeared very radiosensitive to low-dose ionizing radiation both in culture and in immunosuppressed animals. This exquisite radiosensitivity was observed with the highly metastatic single cells which were resting at the time of irradiation. These data are consistent with the dose-response relationship for the radiotherapy of secondary deposits which appears linear with no threshold. Highly metastatic cells at an early stage of growth also appear very sensitive to chemicals and activated immune cells. We propose the medical hypothesis according to which the spread of resting micrometastases should be prevented by a single fraction of total-body irradiation delivered at a dose sufficiently low (below 0.2 Gy) to avoid normal tissue radiotoxicity. Radio-prevention may complement standard treatments for patients with metastases and may be delivered even for patients in whom no distant metastases were detected on tumour diagnosis (M0 stage).

[Concomitant bifractionated radiotherapy and chemotherapy with cisplatin and 5-fluorouracil in locally progressive, non-resectable epidermoid carcinomas of the pharynx: ten years experience at the Antoine Lacassagne center]

PURPOSE

Patients suffering from locally advanced unresectable squamous cell carcinoma of the oropharynx and hypopharynx treated with radiotherapy alone have a poor prognosis. More than 70% of patients die within 5 years mainly due to local recurrences. The aim of this study was to evaluate retrospectively the Antoine Lacassagne Cancer Center's experience in a treatment by concomitant bid radiotherapy and chemotherapy. Evaluation was based on analysis of the toxicity, the response rates, the survival, and the clinical prognostic factors.

PATIENTS AND METHODS

From 1992 to 2000, 92 consecutive patients were treated in our single institution. All of them had stage IV, unresectable squamous cell carcinoma of the pharynx and they received continuous bid radiotherapy (two daily fractions of 1.2 Gy, 5 days a week, with a 6-h minimal interval between fractions). Total radiotherapy dose was 80.4 Gy on the oropharynx and 75.6 Gy on the hypopharynx. Two or three chemotherapy courses of cisplatin (CP)-5-fluorouracil (5FU) were given during radiotherapy at 21-day intervals (third not delivered after the end of the radiotherapy). CP dose was 100 mg/m2 (day 1) and 5-FU was given as 5-day continuous infusion (750 mg/m2/day at 1st course; 430 mg/m2/day at 2nd and 3rd courses). Special attention was paid to supportive care, particularly in terms of enteral nutrition and mucositis prevention by low-level laser energy.

RESULTS

Acute toxicity was marked and included WHO grade III/IV mucositis (89%, 16% of them being grade IV), WHO grade III dermatitis (72%) and grade III/IV neutropenia (61%). This toxicity was significant but manageable with optimised supportive care, and never led to interruption of treatment for more than 1 week, although there were two toxic deaths. Complete global response rate at 6 months was 74%. Overall global survival at 1 and 2 years was 72% and 50% respectively, with a median follow-up of 17 months. Prognostic factors for overall survival were the Karnofsky index (71% survival at 3 years for patients with a Karnofsky index of 90-100% versus 30% for patients with a Karnofsky index of 80% versus 0% for patients with a Karnofsky index of 60-70%, p = 0.0001) and tumor location (55% at 3 years for oropharynx versus 37% for panpharynx versus 28% for hypopharynx, p = 0.009).

CONCLUSION

These results confirm the efficacy of concomitant bid radiotherapy and chemotherapy in advanced unresectable tumor of the pharynx. The improvement in results will essentially depend on our capacity to restore in a good nutritional status the patients before beginning this heavy treatment.

Radiobiological studies on the 65 MeV therapeutic proton beam at Nice using human tumour cells

PURPOSE

To determine the relative biological effectiveness (RBE) for initial and delayed inactivation of cells by a modulated proton beam suitable for the treatment of tumours of the eye, within the spread-out Bragg peak and in its distal declining edge.

MATERIALS AND METHODS

Human tumour SCC25 cells were irradiated with the 65 MeV proton beam at the Cyclotron Medicyc in Nice. Perspex plates of different thickness were used to simulate five positions along the beam line: 2mm corresponding to the entrance beam; 15.6 and 25 mm in the spread-out Bragg peak; 27.2 and 27.8mm for the distal edge. At each position clonogenic survival of the irradiated cells and of their progeny were determined at various dose values. 60Co gamma-rays were used as reference radiation.

RESULTS

RBE values evaluated at the survival level given by 2 Gy of gamma-rays increased with increasing depth from close to 1.0 at the proximal to about 1.2 at the distal part of the peak. Within the declining edge it reached the value of about 1.4 at 27.2 and about 2 at 27.8 mm. For the progeny of irradiated cells, the RBE value ranged from 1.0 to 1.1 within the spread-out Bragg peak and then increased up to a value of 2.0 at the last position. The dose-effect curves for the progeny always had a larger shoulder than for the irradiated progenitors, their alpha parameters being lower by a factor of about 4 and their beta parameters always being higher. The alpha/beta ratio was about 50 Gy for the progenitors and about 6 Gy for their progeny. The incidence of delayed effects increased with dose and with the depth within the beam.

CONCLUSIONS

RBE values for the inactivation of cells irradiated in the spread-out Bragg peak are compatible with the value currently assumed in clinical applications. In the distal declining edge of the beam, the RBE values increased significantly to an extent that may be of concern when the region of the treatment volume is close to sensitive tissues. The yield of delayed reproductive cell death was significant at each position along the beam line.

Results of proton therapy of uveal melanomas treated in Nice

PURPOSE

To present the first results of uveal melanomas treated with the Medicyc Cyclotron 65 MeV proton beam facility in Nice, analyzing the factors that affect the cause-specific survival (CSS), metastatic rate, and reporting the visual outcome.

METHODS AND MATERIALS

This study concerns 538 patients referred by French institutions between June 1991 and December 1996. The eye and tumor parameters were measured using ultrasonography and angiography. Since 1994, CT scans were performed in most patients to help determine the axial length and the shape of the ocular globe. Tantalum clips were inserted around the tumor by the referring ophthalmologist. There were 349 posterior pole tumors (64.9%), 130 equatorial tumors (24.1%), and 59 ciliary body tumors (11%). Two hundred four patients (37.9%) had T1 or T2 tumors, and 334 patients (62.1%) had T3 or T4 tumors. The median tumor diameter was 14.6 mm, and the median tumor height was 5.1 mm. All patients received 52 Gy (57.20 Gy Co-equivalent dose) on 4 consecutive days. The data were analyzed by December 1997.

RESULTS

The CSS was 77.4% at 78 months, the overall survival was 73.8% and the local control was 89.0%. The CSS was not influenced by the patient age or the site of the tumor. It was 81.5% for T1 and T2 tumors, versus 75% for T3 and T4 tumors (P = 0.035). It was found that the tumor diameter, rather than the height, was the most important parameter affecting outcome. The metastatic rate was 8%. It depended on the T stage, tumor diameter and thickness, but not the tumor site. Thirty-eight enucleations were performed, most of them due to tumor progression and/or glaucoma. One-third of the patients in whom visual acuity was adequately scored before and after treatment had a stable, if not improved vision, and half the patients retained useful vision after treatment.

CONCLUSION

The outcome of patients suffering from uveal melanoma and treated with high-energy protons compares favorably with other techniques of treatment. The tumor dimensions affected CSS and metastatic rate. Even though two-thirds of patients had posterior pole tumors, half of them retained useful vision.

Boron neutron capture enhancement (BNCE) of fast neutron irradiation for glioblastoma: increase of thermal neutron flux with heavy material collimation, a theoretical evaluation

Despite the fact that fast neutron irradiation of glioblastoma has shown on autopsies an ability to sterilize tumors, no therapeutic windows have been found for these particles due to their toxicity toward normal brain. Therefore, the Boron Neutron Capture Enhancement (BNCE) of fast neutron beam has been suggested. This paper addresses the problem of fast neutron beam collimation, which induces a dramatic decrease of the thermal neutron flux in the depth of the tissues when smaller irradiation fields are used. Thermoluminescent dosimeter TLD-600 and TLD-700 were used to determine the thermal neutron flux within a Plexiglas phantom irradiated under the Nice Biomedical Cyclotron p(60)+Be(32) fast neutron beam. A BNCE of 4.6% in physical dose was determined for a 10 x 10 cm2 field, and of 10.4% for a 20 x 20 cm2 one. A Dose Modification Factor of 1.19 was calculated for CAL 58 glioblastoma cells irradiated thanks to the larger field. In order to increase the thermal flux in depth while shaping the beam, heavy material collimation was studied with Monte Carlo simulations using coupled FLUKA and MCNP-4A codes. The use of 20 cm width lead blocks allowed a 2 fold thermal neutron flux increase in the depth of the phantom, while shielding the fast neutron beam with a fast neutron dose transmission of 23%. Using the DMF of 1.19, a BNCE of 40% was calculated in the beam axis. This enhancement might be sufficient to open, at least theoretically, a therapeutic window.

Epidermal growth factor receptor and labeling index are independent prognostic factors in glial tumor outcome

The aim of this study was to perform a multivariate analysis including clinical and biological prognostic factors on glial tumor outcome. Seventy-nine patients were analyzed (48 men and 31 women; mean age = 56 years, range = 16-77 years): 7 had a benign glial tumor (grades 1 and 2), 21 had an anaplastic glial tumor (grade 3), and 51 had a glioblastoma (grade 4). Median follow-up was 17.9 months for patients who survived (50 patients died). Biopsies were obtained at time of diagnosis (complete tumor resection in 62 patients and stereotaxic biopsies in 17 patients). Epidermal growth factor receptor (EGFR) was measured by a binding assay, and labeling index (LI) was measured by tritiated thymidine incorporation. EGFR varied from 4 to 73,110 fmol/mg protein (mean = 3912 fmol/mg protein; median = 374 fmol/mg protein; n = 79). LI varied between 0.1 and 16.5% (mean = 6.2%; median = 5.2%; n = 40). Log10 EGFR was significantly and positively correlated with patient age. LI was significantly different according to tumor histology. Univariate Cox analysis (end point was cancer death) showed that age (P = 0.027), log10 EGFR (P = 0.025), and LI (P = 0.0019) were significant continuous variables, the survival being shortened when the covariable increased; tumor resection (P = 0.015, relative risk = 0.45) and histology (P = 0.0009) were significant categorical factors. A multivariate Cox analysis (forward selection) including age, histology, tumor resection, log10 EGFR, and LI revealed that log10 EGFR, LI, and tumor resection were the only independent significant predictors of survival. This multivariate approach reveals that the clinical prognostic factors of glial tumors, namely age and tumor histology, disappear, to the benefit of intrinsic characteristics of the tumor, i.e., EGFR expression and LI, suggesting that coupled EGFR and LI determination could be a useful tool for better evaluation of glial tumor outcome.

Concomitant b.i.d. radiotherapy and chemotherapy with cisplatin and 5-fluorouracil in unresectable squamous-cell carcinoma of the pharynx: clinical and pharmacological data of a French multicenter phase II study

PURPOSE

The aim of this phase II study conducted on unresectable squamous cell carcinoma (USCC) of the oro- and hypopharynx was to associate twice-a-day (b.i.d.) continuous nonaccelerated radiotherapy with concomitant cisplatin (CP)-5-fluorouracil (5-FU) chemotherapy, both given at full dose. Feasibility, efficacy, survival, and pharmacokinetic-pharmacodynamic relationships were analyzed.

METHODS AND MATERIALS

Fifty-four consecutive patients with strictly USCC of oro- and/or hypopharynx received continuous b.i.d. radiotherapy (RT) (2 daily fractions of 1.2 Gy, 5 days a week, with a 6-h minimal interval between fractions). Total RT dose was 80.4 Gy on the oropharynx and 75.6 Gy on the hypopharynx. Three chemotherapy (CT) courses of CP-5-FU were given during RT at 21-day intervals (third not delivered after the end of RT). CP dose was 100 mg/m2 (day 1) and 5-FU was given as 5-day continuous infusion (day 2-day 6: 750 mg/m2/day cycle 1, 750 mg total dose/day cycle 2 and 3). Pharmacokinetics was performed for 5-FU (105 h follow-up) and CP (single sample at 16 h). Special attention was paid to supportive care.

RESULTS

Good feasibility of RT was observed (85.2% of patients with total dose > 75 Gy). Five patients received 1 CT cycle, 34: 2 cycles, and 15: 3 cycles. The most frequent and severe acute toxicities were mucositis with grade 3-4 occurring in 28% at cycle 1 and 86% at cycle 2, as well as neutropenia (43% at cycle 2). Locoregional control at 6 months was observed in 66.7% of patients. No late toxicity above grade 2 RTOG was noticed. CP dose and 5-FU AUC(0-105h) were significantly linked to grade 3-4 neutropenia (cycle 2). Cumulative total platinum (Pt) concentration and Karnofsky index were the only independent predictors of locoregional control at 6 months. Finally, total RT dose and total Pt concentration were the only independent predictors of specific survival.

CONCLUSION

This protocol showed good locoregional response with an acceptable toxicity profile. Pharmacokinetic survey is probably an effective approach to further reduce toxicity and improve efficacy. A multicentric randomized phase III study, now underway, should confirm these encouraging results.