Alternating radiotherapy and chemotherapy schedules in small cell lung cancer, limited disease

A meta-analysis of the timing of chest irradiation in the combined modality treatment of limited-stage small cell lung cancer

The objective of this study was to determine whether initial combined chemoradiation results in superior 1-, 2-, and 3-year survivals in the treatment of limited-stage small cell lung cancer versus sequential or split-course therapy. Using a prospective meta-analysis protocol outlining study inclusion criteria, literature search strategy, and statistical procedures, data from all available randomized controlled trials addressing the above-noted objective were pooled using a fixed effects model (Peto). Results were expressed as summary odds ratios (ORp), and statistical tests for data heterogeneity were performed prior to calculation of ORps. Odds ratios greater than 1.0 favored the experimental arm versus control (i.e., early chest irradiation). If statistical heterogeneity was demonstrated, sensitivity analyses were performed by previously described methods to evaluate possible sources of heterogeneity across the included studies. Pooling data from eight randomized controlled trials enrolling over 1,500 patients showed that early integration of chest radiotherapy with systemic chemotherapy increases overall survival by 34%-216%, depending on the end point of interest. Etoposide (E) plus cisplatin (P) in conjunction with chest irradiation appears to offer the greatest increase in survival versus delayed or split-course radiation therapy and non-EP-containing drug schedules. The available randomized trial data support early concurrent chest radiotherapy and systemic chemotherapy in the form of E and P in the management of limited-stage small cell lung cancer.

Alternating radiotherapy and chemotherapy in limited disease small cell lung cancer

In a pilot study of 29 patients treated for localized small cell lung cancer, three new approaches were introduced, i.e. an increased initial drug dose, an early alternation of chemotherapy and thoracic radiotherapy and initial accelerated and hyperfractionated irradiation. The results were interesting. However, a high rate of fatal toxicity (21%) was observed.

[Pneumonitis after radiotherapy of bronchial carcinoma: incidence and influencing factors]

BACKGROUND

The most important side effect in radiotherapy of lung cancer is pneumonitis. The incidence of pneumonitis was evaluated in a retrospective study in the patient collective of the University of Heidelberg. Therapy related and therapy independent factors have been evaluated.

PATIENTS AND METHODS

In 348 of 392 cases with lung cancer who were treated by local irradiation between January 1989 and January 1992 the patient's records were evaluable for response and toxicity. All patients were treated by megavolt equipment with a conventional fractionation in most cases. Standard target volumes were irradiated including the lymphatic drainage. From a dose of above 30 Gy a technique sparing the spinal cord was chosen. Retrospectively pneumonitis was classified into 4 grades starting from slight symptoms to respiratory insufficiency requiring O2. Grade I and II were summarized to slight, grade III and IV to severe pneumonitis.

RESULTS

Regarding the treatment prior to irradiation patients with primary irradiation were affected in 26.5% (17% slight, 9.5% severe), with postoperative irradiation in 14% (9.3% slight, 4.7% severe), with radiochemotherapy of small cell lung cancer (SCLC) in 15.4% (12% slight, 3.4% severe) by this side effect. These differences were not significant (p = 0.32). The median onset of pneumonitis was 31 days after end of irradiation (severe 23 days, slight 44 days, p = 0.026). By a univariate analysis the total dose at the prescription point was the most important factor (30 to 50.5 Gy 11%, 52 to 59 Gy 15%, 60 to 74 Gy 26%, p = 0.007). High single doses (2.5 Gy) were only applied within a study of radiochemotherapy with a randomised sequential and alternating schedule. So that the increased rate of pneumonitis (42%) is not clearly separable from other influencing variables. A correlation between the applied techniques and the irradiated volume (measured by planimetric methods) was not demonstrable. Regarding the independent factors a high age, female sex and a low FeV1 were unfavourable. However, age and sex corrected FeV1 was not predictive.

CONCLUSIONS

The observed incidence is within the range of literature. By a clinical point of view the total dose is an obvious factor. Also single doses above 2 Gy have to be seen critically (a total dose of 50 Gy). The results confirm the fact that patients with a low FeV1 are not suitable to a high dose irradiation of the chest. In this connection old patients and women also should be seen as patients at risk.

Indications, Results and Techniques of Radiotherapy in the Treatment of Small-Cell Lung Cancer

Aims and background

To define the role of radiotherapy in the treatment of small-cell lung cancer (SCLC) on the basis of clinical data reported in the medical literature.

Methods

Published reports are critically reviewed, with particular attention to randomized trials.

Results

Thoracic radiotherapy has an important role in improving local control and 3-year survival in limited-stage SCLC; radiation should be delivered early in the course of the chemotherapy program, avoiding large volumes and total doses exceeding 40-50 Gy. Thoracic radiotherapy probably has no role in resected patients treated with adjuvant chemotherapy and may even be detrimental in patients with extensive SCLC. Prophylactic cranial irradiation has been shown to reduce the risk of brain relapse, but it is not associated with a consistent increase in survival or cure rate: its use in clinical practice is therefore not advised.

Conclusions

Survival rates approaching 50% at 2 years are now possible in limited SCLC with the integrated effort of the surgeon, the medical oncologist and the radiation oncologist; their strict cooperation appears to be of the utmost importance in the earliest phase of treatment planning.

Adding a reverser (verapamil) to combined chemotherapy overrides resistance in small cell lung cancer xenografts

Small cell lung carcinomas (SCLC) are characterised by chemosensitivity to diverse antitumoral compounds. However, responses are transitory and relapses are commonly observed. We examined the ability of verapamil, a reverser of P-glycoprotein (Pgp)-related resistance, to improve the efficacy of CyCAV combined chemotherapy (Cy, cyclophosphamide (CPA); C, cisplatin (CDDP); A, doxorubicin (ADM);V, etoposide (VP16)), as currently administered to SCLC patients at Institut Gustave-Roussy, France, and adapted to the treatment of nude mice implanted with these tumours. Although Pgp encoded by the MDR1 (multidrug resistance) gene is not the only mechanism for multidrug resistance (MDR), and not all drugs included in this regimen are recognised by Pgp, we anticipated a therapeutic benefit. Four different SCLC lines, expressing the MDR1 gene and recently grafted into nude mice, were used. SCLC-75, SCLC-6 and SCLC-41 originated from untreated patients, and SCLC-74T was derived from a patient treated with a combination of ADM, CPA and VP16. SCLC-41% and SCLC-6T tumours were used after having undergone, respectively, five and nine cycles of in vivo passage and CyCAV treatment of the tumour-bearing nude mice, to reinforce their chemoresistance. The efficacy of the CyCAV regimen, associated with or without verapamil (given 24 h before CyCAV on days 1-5), was tested on the growth of these SCLC. Verapamil (25 mg/kg) improved the antitumour effect of CyCAV in mice bearing SCLC-6T, SCLC-41T and SCLC-75 tumours, although toxicity was observed. Verapamil modestly delayed the plasma clearance of ADM. Two daily injections of 10 mg/kg of verapamil, administered at a 3 h interval, proved to be effective, whereas the same total dose administered as a bolus was not. These results indicate that the association of some reversers of MDR, including drugs possibly interacting with Pgp, might potentiate SCLC combined chemotherapy.

Early alternating chemotherapy and radiotherapy schedule in limited disease stage small cell lung cancer

44 patients with limited small cell lung cancer were treated with six cycles of chemotherapy (cisplatinum 60 mg/m2 day 1, doxorubicin 40 mg/m2 day 1, etoposide 100 mg/m2 days 1-3) alternating with three courses of mediastinal irradiation, the first one starting 7 days after the first day of chemotherapy. A total dose of 55 Gy was delivered. Prophylactic cranial irradiation (30 Gy after the third cycle of chemotherapy) was left to the physician's discretion. 4 patients had radical surgery before combined modality treatment. 29 patients finished the scheduled program. The complete response rate (bronchoscopically confirmed) was 25.6% after two cycles of chemotherapy and 41% at the end of treatment. Median survival time was 17.2 months, with an estimated survival of 32% at 2 years. Main toxicity was haematological with one early toxic death and six premature interruptions of treatment. We conclude that this treatment modality is feasible and efficacious. Prospective studies comparing chemotherapy with alternating or concurrent early radiotherapy schedules in limited disease small cell lung cancer are needed to determine the best treatment modality.

Long term results of a phase I/II study of aggressive chemotherapy and sequential upper and lower hemibody radiation for patients with extensive stage small cell lung cancer

BACKGROUND

A Phase I/II study of an aggressive six-drug chemotherapy regimen followed by the use of sequential hemibody radiation therapy as a possible non-cross-resistant systemic treatment was undertaken for patients with extensive stage small cell lung cancer.

METHODS

The 20 enrolled patients received 7 cycles of cyclophosphamide-based chemotherapy. The first cycle consisted of cyclophosphamide, doxorubicin, etoposide, vincristine, and lomustine. Subsequent cycles used a regimen of doxorubicin alternating with cisplatin. Thoracic radiation was delivered in a split-course fashion during the first week of chemotherapy cycles 5 and 6 (2000 cGy in five fractions during each week). Prophylactic cranial radiation was delivered in a split-course fashion during the first week of chemotherapy cycles 2 and 3 (1700 cGy in 5 fractions during each week). After the 7 cycles, patients received 600 cGy upper hemibody radiation followed by 800 cGy lower hemibody radiation.

RESULTS

Nineteen of 20 patients were evaluable for toxicity and response to treatment. Hematologic toxicity accounted for treatment delays or decreased doses in 16 of 19 patients. Thirteen patients completed the initial 7 cycles; progressive disease was the only reason for discontinuing treatment. Two patients had fatal hematologic complications after lower hemibody radiation. Three patients had severe or greater peripheral neurologic toxicity, two had severe central neurologic toxicity, and one had severe cardiac toxicity. Of 19 patients, 9 achieved a complete response; median survival was 11.5 months. Five-year progression free survival and 5-year overall survival were 27% and 16%, respectively.

CONCLUSIONS

This aggressive regimen is feasible for patients with extensive stage small cell lung cancer; however, hematologic-related mortality after lower hemibody radiation suggests that future investigations should be initiated at lower initial doses of lower hemibody radiation. Long term survival of the patients suggests that sequential hemibody radiation treatment warrants further investigation.

Dealing with initial chemotherapy doses: a new basis for treatment optimisation in limited small-cell lung cancer

Treatment of patients with small-cell lung cancer (SCLC) remains disappointing despite initially high complete response rates. The dramatic initial chemosensitivity of tumor cells is rapidly thwarted by the early emergence of chemoresistant clonogenic cells, regardless of front line treatments. Although a dose-response relationship is well established its effect on survival is inconclusive. From 1980 to 1988, 202 patients with limited SCLC were included in four consecutive trials using an alternating schedule of thoracic radiotherapy and chemotherapy. Despite an increase in chemotherapy and/or the total radiation dose, no significant difference was observed between the four trials in terms of response, disease-free or overall survival. However, a retrospective analysis performed on a total of 131 consecutive patients led us to postulate that a moderate increase in the initial dose, i.e. first course, of cisplatin and cyclophosphamide, could improve overall survival. From 1988 to 1991, 105 consecutive patients were included in a large randomized trial to address this question. The difference in treatment options only concerned the initial doses of cisplatin (80 vs. 100 mg/m2) and cyclophosphamide (900 vs. 1200 mg/m2). According to the triangular test used in this study the trial was closed after inclusion of 105 patients, 32 months after the start of the study because, at that time, overall survival was significantly better in the higher-dose group (p = 0.001). This debatable concept of dose-intensity having an impact on survival offers new possibilities for the management of SCLC. The contribution of hematopoietic support may help to validate this concept.

Radiotherapy of lung cancer

Radiotherapy is the most common nonsurgical treatment for patients with lung cancer. Its value in controlling specific cancer related symptoms is undisputed and can be achieved with unsophisticated and undemanding schedules. However, these treatment regimens cannot be expected to produce durable local control or significant impact on survival. Their use cannot be generally accepted for all inoperable patients. The use of high-dose radiotherapy with curative intent has been brought into disrepute by often inappropriate patient selection and subsequently poor results. In a number of small pilot studies, survival comparable to surgical series can be achieved in operable patients. Safe delivery of high-dose radiotherapy to intrathoracic tumours represents a formidable technical challenge. The sophisticated treatment planning which is necessary and consistent diagnostic evaluation is often lacking in practice when the value of local therapy is perceived as minimal. Recent developments in radiation technology, tumour biology and understanding of normal tissue responses bring an opportunity to design new and more effective treatment schedules. New developments in systemic therapy far from making thoracic irradiation obsolete, demand higher rates of durable local control. The interrelationships between toxicities to normal tissues and potential advantage in antitumour activity bring further challenges in design of optimal combined modality schedules. The challenge facing the Radiation Oncologist interested in thoracic malignancies is how to balance the multiple and often conflicting possibilities and formulate novel schedules that can be evaluated in practice. A further challenge is how to facilitate the introduction of these resource-intensive strategies into the real world of shrinking resources and increasing waiting lists. The potential gains may be individually small but with the numerical importance of lung cancer may have a global impact.

The role of radiation oncology in small cell lung cancer

Small cell lung cancer comprises a histologic subgroup of bronchogenic carcinomas distinguished particularly by a responsiveness to cytotoxic agents, and equally by a strong tendency to disseminate, both to mediastinal and distant sites. At one time considered suitable only for short-term palliation by radiation therapy, this disease is now managed by both systemic and regional approaches, typically with close integration of radiotherapy and chemotherapy. Thoracic irradiation produces modest improvements in both survival and local control in small cell lung cancer, when the clinical extent is limited to the chest. The optimal parameters of dose, treatment volume, fractionation, and temporal integration with chemotherapy are not yet defined. When the disease is more extensive radiotherapy plays a useful palliative role. New biological insights are being brought to the clinic, and have stimulated new therapeutic initiatives in the treatment of this disease. Modified radiotherapy fractionation schemes and sophisticated integration of chemotherapy and radiation therapy have resulted in further advances. In addition to improved response rates and median survivals, combined modality approaches suggest, in addition, the possibility of cured subset in cases of disease confined to the chest. The adverse effects of thoracic irradiation are manageable and the more serious can be prevented with careful attention to volume and technique. Radiotherapy offers relief of many symptoms and cost-effective palliation of metastatic lesions in most body sites. Considered as a significant problem in oncology, and apart from efforts at primary prevention, major progress in this disease is most likely to result from research focussed on the limited disease subset, which, unfortunately, consists of no more than half the incident cases. These patients have a median survival of 12-18 months, and are sufficiently numerous that it is possible to detect meaningful treatment progress in clinical trials of a reasonable size. Nevertheless, the marked advances of two decades ago, when chemotherapy first came into widespread use, are not seen today. Progress is now more likely to be seen in modest improvements in survival or tumor control rates when control and experimental regimens are compared statistically in large trials or in meta-analyses. While the evidence supports the use of thoracic radiotherapy the ideal drug combination is unknown, and there is a real need for new agents of substantially greater activity than those available today. While more rational combinations of agents may be possible, it seems likely that the limits of tolerance are being reached.(ABSTRACT TRUNCATED AT 400 WORDS)

Toxicity of thoracic radiotherapy on pulmonary function in lung cancer

Physiological changes in pulmonary function (PF) as a result of radiation therapy (RT) or radiation therapy plus chemotherapy (RT + CT) for unresectable lung cancer were evaluated in an ongoing prospective study and an attempt was also made to define a guideline which can be used to minimize adverse effect of RT on pulmonary function before RT is given. The study design consisted of: (a) standard overall pulmonary function test (PFT); (b) regional PFT, i.e. a quantitative analysis of regional distribution of ventilation, perfusion and volume using 13N and a positron camera before RT; and (c) follow-up studies of standard PFT every 6 months for 3 years after RT or RT + CT. Predicted post-RT PF prior to RT was calculated by a formula: predicted FEV1 after RT = FEV1 before RT x (1 - an average of the percent of ventilation and perfusion contributed by lung tissue within the RT treatment volume). A total of 267 patients with unresectable, but still potentially curable lung cancer by RT were entered into this study, and 135 patients who were free of recurrence underwent repeat studies. Loss of PF as a result of RT is closely related to the degree of PF reserve prior to RT. Patients with FEV1 > 50% of the predicted showed a statistically significant decrease in FEV1, FVC, MBC, peak expiratory flow rate and DLCO, i.e. a 22% loss of the initial value. Airway resistance was increased by 31%. Two-thirds of this group of patients showed a decrease in PF as predicted by the above formula. For patients with limited PF reserve defined by FEV1 < 50% of the predicted, the pattern of PF loss after RT was quite different. An improvement in PF although it was < or = 10%, contrary to the prediction, was noted in 50% of patients, and another 37% of patients showed a small decrease in PF (< or = 10% of the initial value). Only 13% of patients showed a loss of pulmonary function as predicted by regional PF data. Patients with a significant shift (> 10%) of ventilation and/or perfusion to the uninvolved side of the lung by centrally located primary tumor or involved lymph nodes showed an increase in PF in 60% of patients after RT, and another 20% of patients showed a minor decrease in PF (< 10% of the initial value). Only 20% of these patients showed a decrease in pulmonary function as predicted by regional PF data. Guidelines for minimizing adverse effect of RT on PF, which are based on the initial PF reserve and regional PF data, are presented.

Patterns of failure following loco-regional radiotherapy in the treatment of limited stage small cell lung cancer

PURPOSE

The probability of treatment resistant cells developing in a tumor, such as small cell lung cancer (SCLC) which has a rapid cell cycle time, is a function of the number of tumor cells present and of time. Theoretically, the development of resistance to chemotherapy and radiotherapy should be minimized by using all treatment modalities early in the treatment program.

METHODS AND MATERIALS

The importance of the timing of loco-regional radiotherapy was assessed in a multi-institution randomized study. Three hundred and eight patients with limited small cell lung cancer (LSCLC) were given three cycles of cyclophosphamide, doxorubicin and vincristine alternating with three cycles of etoposide and cisplatin. In addition, patients were randomized to receive locoregional radiotherapy: 40 Gy in 15 fractions in 3 weeks with treatment planning techniques to limit the spinal cord dose to be < or = 35 Gy either with the first cycle (early) or with the sixth cycle of chemotherapy (late). Responding patients received prophylactic brain irradiation (25 Gy in 10 fractions in 2 weeks) after completion of locoregional radiotherapy and chemotherapy.

RESULTS

96% of the 155 eligible patients allocated to the "early" arm and 87% of the 153 allocated to the "late" arm received locoregional radiotherapy; 26 patients did not receive locoregional radiotherapy. The mean field sizes were similar in both arms. The mean radiation doses were significantly less in the "early" arm (p = 0.0319 Wilcoxon rank sum test). Any differences in the frequency of toxicities were minor. All patients have been followed for at least 2 years and the median follow up is 4 years. 64% had a complete response in the "early" arm compared with 56% in the "late" arm (p = 0.137). Survival was measured from the start of chemotherapy. There was a significant improvement in survival in the "early" arm; median survival was 21.2 months compared with 16.0 months in the "late" arm (p = .008 log rank test). Survival at 2, 3, and 4 years was 40%, 32%, and 25%, respectively, for the "early" arm and 33%, 22%, and 15% for the "late" arm. There were 232 (75%) recurrences among those patients whose disease recurred. The proportion who had local recurrence within the radiation field was 41% and 39% for "early" and "late" treatment arms respectively. The proportion of brain metastases in the "late" arm (28%) was significantly higher than in the "early" arm (18%) p = .0425 Fishers' exact test.

CONCLUSION

We conclude that early administration of locoregional radiotherapy in a combined modality treatment is superior to late consolidative locoregional radiotherapy in limited small cell lung cancer.

Consolidative thoracic radiotherapy and prophylactic cranial irradiation in limited disease small cell lung cancer

Between 1983 and 1990, 128 patients with limited disease small cell lung cancer (SCLC) received consolidative thoracic irradiation after reaching a complete (CR) or partial response (PR) to combination chemotherapy. Patients in CR (n = 85) received 35-36 Gy in 12-14 fractions and patients in PR (n = 43) 24-30 Gy in 3-6 fractions. Until 1989, prophylactic cranial irradiation (PCI) was given to patients in CR. There was no significant difference in survival between the CR and PR group. However, patients with residual tumor detected by radiology or bronchoscopy or cyto-/histology had significantly longer survival than those with residual tumor demonstrated by more than one of the above methods of investigation. Overall, local progression was observed in 22% and distant dissemination in 63% of patients. The rate of brain metastases was significantly lower in patients treated with methotrexate and nitrosurea containing schedules and PCI, compared to those who were treated with other schedules (irrespective of PCI).

Limited disease small cell lung cancer: alternating combination of doxorubicin, etoposide, ifosfamide and hyperfractionated radiotherapy. Final results of a multicentric pilot study for the Groupe Lyonnias d'Oncologie Thoracique (GLOT)

In order to evaluate the effect on prolonging survival of alternating chemotherapy and radiotherapy schedules in patients with limited disease small cell lung cancer, 89 patients were included in a multi-institutional pilot study between January 1986 and May 1989. Treatment consisted of induction chemotherapy using the combination of doxorubicin, etoposide and ifosfamide (AVI) for four consecutive courses, followed by two cycles of the VI chemotherapy alternating with three hyperfractionated radiotherapy courses and then followed by two additional courses of AVI. Objective response to the four cycles of AVI combination was observed in 65 patients (75%). Thirteen out of 30 patients (44%) who were in partial response (PR) after induction chemotherapy were converted into complete response (CR) after the three alternating courses of chemotherapy and radiotherapy. The principal side effect related to combined modality treatment was acute radiation pneumonitis (21.5% cases) reversible except one which resulted in toxic death, and a second with chronic lung fibrosis with permanent WHO Grade 2 dyspnea (14%). Local relapse was observed in 47% of the patients who were considered in CR at the end of the treatment program and cerebral metastases were the first site of detectable relapse in 25% cases. The 3-year actuarial disease-free survival of the 89 patients is 5%, and the median actuarial survival is 14 months. This study shows that the promising survival rates seen in our previously published interim analysis were not maintained. Reasons for this might include the choice of a non cisplatinum containing induction chemotherapy, the late introduction of thoracic irradiation and/or to the use of non-restrictive criteria for selecting patients.

A randomized trial of delayed thoracic radiotherapy in complete responder patients with small-cell lung cancer. Petites Cellules Group

In small-cell lung cancer, the optimal combination of chemotherapy and radiotherapy is not clearly established. To assess the value of delayed thoracic radiotherapy, we performed a randomized clinical trial in 53 complete responder patients after eight courses of chemotherapy. Twenty-seven patients received a mean of 46.5 Gy-equivalent of radiotherapy and 26 patients received no treatment until relapse. No patient dropped out of the study. Median survival time from radiotherapy randomization was 316 days in the radiotherapy group and 496 days in the no radiotherapy group. No difference was observed in survival between the two groups (p = 0.66, log-rank test) perhaps because of the small sample size. In fact, this delayed thoracic radiotherapy seemed to worsen the outcome of complete responders with small-cell lung cancer and should be avoided.

Small-cell lung cancer: an overview of issues in therapy

As one of the few chemo- and radiosensitive neoplasms among the common epithelial solid tumors of adults, small-cell lung cancer has long tantalized clinical investigators. Although for the last 15-20 years therapy has yielded high remission rates, including substantial complete remission rates, results have not improved very much over nearly two decades of intensive therapeutic research, and long-term disease-free survival remains an elusive goal for the large majority of patients. At this point the number of promising untested hypotheses in therapy is quite small, and major advances will probably have to await either the serendipitous discovery of much more active drugs than we now possess, or else the purposeful development of new approaches based on insights into the nature of the transformed state and the biology of SCLC itself.

Response of a multidrug-resistant human small-cell lung cancer xenograft to chemotherapy

Small-cell lung carcinomas (SCLC) are highly responsive to various chemotherapies. However only a minority of patients benefit from long survival. SCLC patients treated at the Institut Gustave Roussy received a combined chemotherapy (CCAV) including cisplatin, cyclophosphamide (Cpa), Adriamycin (doxorubicin; Adm) and vepeside (VP16). We report here the intrinsic sensitivity of a small-cell lung carcinoma, designated SCLC-6, grafted in nude mice. This xenografted tumour was derived from an untreated patient. The CCAV regimen given to the patient donor of the tumour sample resulted in a complete response followed by recurrence and death, 8 months after the initial cure. The expression of P-glycoprotein encoded by the MDR1 gene was detected with the C219 antibody on the membrane of SCLC-6 tumour cells. When given to SCLC-6-tumour-bearing nude mice, CCAV induced a strong inhibition of tumour growth (84% of growth inhibition, 20 days after start of the treatment), but no cure. Intensification of CCAV doses did not improve the response. The efficacy of individual agents of the CCAV, given at maximal tolerated doses was analysed. Only cisplatin (10 mg/kg) and Cpa (3 x 50 mg/kg) inhibited SCLC-6 growth (79% and 100% inhibition respectively), VP16 (3 x 24 mg/kg) was poorly efficient (42%) and Adm (10 mg/kg) not at all. Two-drug combinations such as cisplatin plus VP16 or cisplatin plus Cpa inhibited tumour growth (81% and 70%, respectively). Curiously, the efficacy of Cpa, given in combination with cisplatin was less than that of Cpa alone. Repeated treatments with CCAV administered to mice at each in vivo passage of the tumour induced a loss of chemosensitivity, which was observed until the ninth passage. An improvement of the therapeutic response was obtained by adding a headline reverser of multi-drug resistance, verapamil (25 mg/kg), to CCAV (81% versus 63% inhibition). MDR1-related resistance appeared to play a role in the failure of SCLC-6 chemotherapy; frequent recurrences after treatment with cisplatin and Cpa, two drugs that are not recognized by the P-glycoprotein, indicated that other modes of resistance were simultaneously active.

Prophylactic cranial irradiation: advantages and disadvantages

Anaplastic small cell carcinoma of the lung is a disease that responds to multiagent systemic therapy. Unfortunately, a high incidence of central nervous system (CNS) relapse has been observed by many investigators. Cranial irradiation has been successfully used in acute lymphoblastic leukemia to reduce CNS relapse and improve survival. A similar application of prophylactic cranial irradiation in patients undergoing therapy for small cell anaplastic carcinoma of the lung has been noted to decrease CNS relapse from approximately 25% to approximately 5%. However, CNS toxicity has been noted to occur with CNS prophylaxis. We can reduce the incidence of CNS toxicity by using modern treatment schedules and avoiding the use of doxorubicin with irradiation. Prophylactic cranial irradiation delivered to those patients who obtain a complete remission in response to induction chemotherapy can reduce the incidence of CNS relapse and can usually be delivered with minimal CNS toxicity. Unfortunately, long-term disease control with systemic agents is poor. Until more effective systemic agents are developed, the role of prophylactic cranial irradiation is one of palliation rather than improving survival.

Alternating chemo-radiotherapy with cisplatin and 5-fluorouracil plus bleomycin by continuous infusion for locally advanced undifferentiated carcinoma nasopharyngeal type

More than 80% of undifferentiated carcinoma nasopharyngeal type patients with N3 disease (AJC-UICC 1987) will die with or from distant metastases within 3 years after the first symptom. From February 1986 to November 1987 30 consecutive patients with very advanced local disease were entered in a programme with chemotherapy-radiotherapy (CT-RT) alternation after a thorough work-up to eliminate the possibility of distant metastases.

PROTOCOL

two cycles of cisplatin 100 mg/m2 day 1, bleomycin 15 mg intravenously day 1 and 16 mg/m2 per day by continuous infusion days 1-5; 5-fluorouracil (5-FU) 650 mg/m2 per day by continuous infusion days 1-5 4 weeks apart. This was followed by two series of high-energy radiotherapy, 35 Gy/3.5 weeks, with a third chemotherapy cycle in between. 27 men and 3 women were treated, the median age was 37 years (range 17-71) and the mean WHO performance status was 1 (range 0-3). TNM classification: 15 T4, 9 T3, 6 T2, 28 N3 and 2 N2c. 18 patients had nodes larger than 8 cm and 24 had bulky bilateral cervical nodes. Toxicity for this protocol was moderate, nausea and vomiting being the main side-effects. Results after two CT cycles were 3 complete responses (CR; 10%), 22 partial responses (PR; 73%), 2 disease stabilizations, 2 progressions, and 1 patient inevaluable. Of the 30 patients, 27 patients completed the CT-RT protocol, 2 patients died before radiotherapy and 1 refused treatment after 2 days on protocol. 25 patients were in CR 3 months after the end of radiotherapy. As of August 1991, with a median follow-up of 55 months (range 43-63), there are 17 patients alive, 2 of them with active disease and 15 are NED (2 after salvage therapy).

A Medical Research Council phase II trial of alternating chemotherapy and radiotherapy in small-cell lung cancer. The Medical Research Council Lung Cancer Working Party

In a non-randomised study in six centres in the UK, 24 patients with previously untreated small-cell lung cancer of limited extent were treated with a regimen of alternating chemotherapy and radiotherapy to assess response, toxicity, and the feasibility of applying such a regimen on a multicentre basis in the UK. The intention was to give six courses of chemotherapy on five consecutive days at 4-week intervals: etoposide 75 mg m-2 on days 1, 2, and 3; doxorubicin 40 mg m-2 on day 1; cisplatin 100 mg m-2 on day 2; and cyclophosphamide 300 mg m-2 on days 2, 3, 4 and 5. A dose of 20 Gy thoracic radiotherapy was to be given following the 2nd and the 3rd courses, and one of 15 Gy following the 4th course. After 12 patients had been admitted, the cisplatin dosage was reduced to 80 mg m-2 because of unacceptable toxicity. Two patients were withdrawn during treatment on review of their histology because their diagnosis was found to be incorrect. Only one patient of the 12 treated with cisplatin 100 mg m-2 was able to complete treatment, compared with five of the eligible ten given the lower dosage. Among the 22 patients with confirmed small-cell disease, a complete response was reported in 14 (64%) and a partial response in a further three (total response rate 77%). Myelosuppression was the commonest serious adverse effect. It occurred in 19 of the 24 patients and gave rise to septicaemia in five, four of whom were receiving the higher cisplatin dose. Sixteen patients required blood transfusion and ten platelet transfusion. Vomiting, oesophagitis, and peripheral neuropathy occurred in 12, four and four patients, respectively, and radiation pneumonitis developed in two. Treatment was considered a contributory cause of death in four. The working party concluded that the alternating regimen was feasible in only a small proportion of centres in the UK, and decided not to embark on a multicentre randomised trial comparing alternating with conventional scheduling.

Late consolidative radiation therapy in the treatment of limited-stage small cell lung cancer

Two hundred twenty-three patients were enrolled on this randomized Phase III trial testing the value of late consolidative involved-field radiation therapy in the treatment of limited-stage small cell lung cancer (SCLC). Patients were treated with induction chemotherapy consisting of alternating cycles of procarbazine, vincristine, lomustine, and cyclophosphamide (POCC) and etoposide, doxorubicin, and methotrexate (VAM) for 6 to 9 months. Responding patients were then randomized at 6 or 9 months to chemotherapy alone or to involved-field radiation therapy. All partial and complete responders received prophylactic cranial irradiation. Of the 180 eligible and evaluable patients, 80 (44%) achieved a complete response and 39 (22%) achieved a partial response (overall rate of response, 66%). Actuarial median survival time was 11.6 months, with 16% of patients surviving 2 years and 11% surviving 5 years. Forty-eight patients were randomized to chemotherapy alone (24 patients) versus chemotherapy plus involved-field radiation therapy (24 patients). There were no significant differences in time to progression or survival between those patients receiving or not receiving involved-field radiation therapy. The thorax was the site of first relapse in 58% of patients randomized to chemotherapy alone versus 29% in patients randomized to chemotherapy plus involved-field radiation therapy (P equals 0.042). The major acute toxicity was reversible myelosuppression, and the major late toxicity was chronic central nervous system dysfunction. The authors conclude that the addition of late consolidative radiation therapy to induction chemotherapy in the treatment of limited-stage SCLC is well tolerated and improves local control, but does not improve time to progression or rates of survival.

Limited small cell lung cancer: the effect of radiotherapy on local control following response to chemotherapy

The survival and rate of chest infield relapse was examined in 48 patients with limited disease small cell lung cancer (LSCLC) who had achieved complete (CR) or partial response (PR) following three courses of chemotherapy. During 1985-1986 chemotherapy consisted of carboplatin and etoposide and during 1986-1987, of etoposide, carboplatin, cyclophosphamide, and vincristine (ECCO). After three courses of chemotherapy, chest irradiation (50 Gy in 25 fractions over 5 weeks) was given to encompass the original tumor volume. Complete responders were also given prophylactic cranial irradiation, 30 Gy in 10 fractions over 2 weeks. Overall median survival of all patients receiving chest irradiation was 17 months from commencement of radiotherapy. The infield relapse-free survival at 24 months was 49% (95% confidence interval: 32-66%). Patients who had only achieved a PR at the time of irradiation were more likely to relapse in the chest than complete responders (p = 0.09). We conclude that local relapse remains a major cause of failure in patients with LSCLC in spite of sequential high dose radiotherapy given to patients who have responded to chemotherapy.

Rationale for different chemotherapeutic and radiation therapy strategies in cancer management

The two primary therapeutic strategies in cancer have been to give either chemotherapy and radiation therapy together or give a complete course of one treatment modality before starting the second. Clinical studies show that toxicity has been one of the major deterrents to substantial improvements in cancer management when the two modalities are administered together. On the other hand, the prolonged time necessary to administer all of one modality followed by the other makes it likely that repopulation of the tumor during sequential treatment will diminish therapeutic effectiveness. A third strategy of giving chemotherapy and radiation therapy has been developed. This new regimen was designed to give chemotherapy initially, maintain the chemotherapy schedule to avoid any reduction in its effectiveness, and add radiation therapy as early as possible in between courses of chemotherapy to minimize the development of cross resistance. One of the primary objectives of alternating chemotherapy and radiation therapy is to increase the therapeutic index by reducing toxicity without a significant reduction in therapeutic effectiveness. Recent clinical, experimental, and theoretic results with radiation therapy and chemotherapy for cancer management emphasize the necessity of giving both modalities with the greatest intensity possible in the initial phase of induction therapy. Cancer treatment scheduling determines the toxicity and thereby limits the dose intensity that can be tolerated. Scheduling may also govern the antitumor effect directly; however, normal host tissue makes the determination of the direct effects on the tumor difficult, if not impossible, in clinical studies. Well-defined experimental solid-tumor systems provide the means for determining directly the relationship between toxicity and antitumor effects in relation to tumor burden and total therapeutic dose. In addition, its relationship to dose intensity and scheduling can be determined by the using more sophisticated research techniques, such as response surface methods. Well-defined clinical protocols to determine how to interact chemotherapy with radiation therapy more effectively hold considerable potential for rapid improvement in treatment of radiosensitive and chemosensitive cancers.

Intercalated radio-chemotherapy in small cell lung cancer: toxicity and implications for future regimens

Thirty-six patients with small cell lung cancer have been treated using chemotherapy comprising carboplatin, ifosphamide and etoposide. A total of six cycles of chemotherapy were given. In 15 patients with limited disease intercalated radio-chemotherapy was used in which two 5-day courses of hyperfractionated radiotherapy were given to the thorax after the first and second cycles of chemotherapy. Each course of thoracic radiotherapy delivered 15 Gy in 15 fractions over 5 days. Oesophagitis occurred in 7 patients (40%), in 5 of whom this was severe (WHO grade 3). Radiological pneumonitis developed in 6 patients (40%) with subsequent fibrosis in 2 patients. These effects are greater than would be expected with this dose of radiation alone and reflect marked enhancement of normal tissue toxicity.

Alternating radiotherapy and chemotherapy schedules in limited small cell lung cancer: analysis of local chest recurrences

An analysis of the chest recurrences was conducted in 72 consecutive patients with limited small cell lung cancer treated in two successive phase II trials alternating six induction chemotherapy courses and three series of thoracic radiotherapy, followed by maintenance chemotherapy. The total radiation dose was 45 Gy (3 series of 15 Gy) in the first trial, and 55 (20, 20 and 15 Gy) in the second. The effect of the irradiated volume was investigated by comparing the local relapse rates in the group of patients treated by radiation fields encompassing the initial tumor volume to another group in which the initial target volume was not fully covered by radiation fields. The definition of these two groups was performed retrospectively by examination of radiological, fiberoptic bronchoscopy initial findings, technical radiation charts and check films. The local recurrence rate were 33 and 36% in each group (no significant difference). This finding could suggest that tumor shrinkage after chemotherapy might allow the use of "reduced" radiation volumes. However, the limited number of patients does not permit a definite conclusion. The effect of radiation dose was investigated by comparing the local control rates in the two consecutive trials which delivered 45 and 55 Gy, respectively. No difference in long-term local control was found: the addition of 10 Gy in the second trial only seemed to delay the appearance of local recurrences by 6 months. Twenty percent of patients died from a local relapse without evidence of distant metastases.(ABSTRACT TRUNCATED AT 250 WORDS)

Single-dose and fractionated irradiation of four human lung cancer cell lines in vitro

Four established human lung cancer cell lines were exposed to single-dose irradiation. The survival curves of 2 small cell lung carcinomas (SCLC) were characterized by a limited capacity for repair with small and moderate shoulders with extrapolation numbers (n) of 1.05 and 1.60 respectively. Two non-small cell lung carcinoma (NSCLC) cell lines, one squamous cell (SQCLC) and one large cell (LCLC) had large shoulders with n-values of 73 and 15 respectively. The radiosensitivity when measured as D0 did not, however, differ as much from cell line to cell line, with values from 1.22 to 1.65. The surviving fraction after 2 Gy (SF2) was 0.24 and 0.42 respectively in the SCLC cell lines and 0.90 and 0.88 respectively in the NSCLC cell lines. Fractionated irradiation delivered according to 3 different schedules was also investigated. All the schedules delivered a total dose of 10 Gy in 5 days and were applied in 1, 2, and 5 Gy dose fractions respectively. Survival followed the pattern found after single-dose irradiation; it was lowest in the SCLC cell line with the lowest SF and highest in the two NSCLC cell lines. In the SCLC cell lines all schedules were approximately equally efficient. In the LCLC and in the SQCLC cell lines, the 5 Gy schedule killed more cells than the 1 and 2 Gy schedules. The results indicate that the size of the shoulder of the survival curve is essential when choosing the most tumoricidal fractionation schedule.

Alternating chemotherapy and radiotherapy combination for bulky stage I and II intermediate and high grade non-Hodgkin lymphoma: an update

In 1980, based on experimental and clinical data, a protocol was developed at the Institut Gustave-Roussy (IGR), alternating eight monthly courses of chemotherapy (CHVP) and two, then three, radiotherapy sequences (15 Gy in 6 fractions and 10 days to the initially involved areas), for early stage unfavourable histology non-Hodgkin lymphomas (NHL). The results are updated for 55 selected patients presenting with bulky stage I and II NHL, intermediate and high grade according to the Working Formulation. Five-year overall survival rate was 69% and freedom from progression was 68%. Early haematologic and digestive tolerance was satisfactory, probably because a 10-15-day interval was respected between chemotherapy and radiotherapy and vice versa. No late toxicity was detected in 39 patients who presented with head and neck localizations; xerostomia was found to be only mild and transient. All patients given mediastinal irradiation experienced radiological mediastinitis, but functional impairment was usually moderate. One of the 4 patients who received 3 x 15 Gy radiotherapy courses to part of the abdomen, died of small bowel obstruction and perforation. The study demonstrated the feasibility of an alternated schedule of chemotherapy and radiotherapy, with satisfactory results in terms of long-term survival. However, the few late complications which were detected after irradiation of the abdomen or of the thorax led to an alteration of the initial scheme when these volumes are to be treated.

Thoracic radiotherapy variables: influence on local control in small cell lung cancer limited disease

In limited small cell lung cancer (LSCLC), the high local failure rate of chemotherapy by itself (60-100%) and with the addition of external beam radiotherapy (approximately 30%) has led to investigation of methods to improve local control. To that end, we integrated Platinum 60 mg/m2, d. 1, 22 and Etoposide 120 mg/m2, d. 4, 6, & 8; 25, 27 & 29 with concurrent twice-daily 150 cGy (total dose: 4500 cGy). Of 32 consecutively referred patients, 4 with variant histology, 31 were evaluable for toxicity, response, and survival. Two of 4 variant histology patients responded, and 27 of 27 pure small cell responded, p = 0.005. CT scans were inaccurate at forecasting survival. Of 17/32 patients considered "positive," 59% of these were survivors; of those considered "negative," 47% were survivors, p = N.S. Radiation portals were volumetrically conservative; the supraclavicular fossa was included infrequently and the contralateral hilum not at all. Local failure occurred in only 1/27 patients (4%). All four variant patients failed locally, p = 0.001. With a median follow-up of 43 months, the actuarial disease-free survival remains nearly 50%. Variant histology is more predictive of local control than the physical factors of dose or volume.

Alternating radiotherapy and chemotherapy in 173 consecutive patients with limited small cell lung carcinoma. GROP and the French Cancer Center's Lung Group

One-hundred seventy-three patients with limited small cell lung cancer were included in three consecutive protocols alternating radiotherapy and chemotherapy. The alternating schedule consisted of six courses of chemotherapy (doxorubicin, VP16213, cyclophosphamide, and methotrexate in the first protocol; methotrexate being replaced by cisplatinum in the other two protocols) and three series of thoracic radiotherapy delivering a total dose of 45, 55, and 65 Gy in each consecutive protocol. Radiotherapy was started after the second course of chemotherapy. A 1-week gap was respected between each course of chemotherapy and each series of radiotherapy. Seventy percent of patients were in complete remission at the end of the induction treatment. The actuarial 5-year local control was 60% and the 5-year overall survival was 18%. Sixty percent of patients developed distant metastases. The death rate unrelated to cancer was 10%. These results show that alternating radiotherapy and chemotherapy schedules are reproducible, and provide a consistent long-term local control and a long-term survival rate exceeding 15% in limited disease.

The value of adjunctive radiotherapy when chemotherapy is the major curative method

Chemotherapy is the main treatment in many human malignancies including non-Hodgkin lymphomas and some solid tumors such as those of embryonal origin and small cell lung carcinomas. The high responsiveness to chemotherapy of these tumors has led some groups to treatment policies limited to chemotherapy alone. A long follow-up has shown a high incidence of recurrence in the sites that were initially macroscopically involved. Some randomized trials evaluating the adjunction of radiotherapy to chemotherapy have shown that a failure in local control can be associated with a decreased overall survival. The survival benefit of combined chemotherapy and radiotherapy is generally moderate and is best evaluated by randomized trials entering a large number of patients. The adjunction of radiotherapy to chemotherapy can lead to an increased rate of acute and late toxicity that may overshadow a therapeutic benefit. Critical points of the combined approach are: types of drugs, radiotherapy parameters, radiotherapy-chemotherapy doses, and timing. In this review, two clinical models, one with a low potential of cure, limited small cell lung cancer, and one with a medium potential of cure, non-Hodgkin lymphoma, are reviewed emphasizing information obtained from randomized trials. The modalities of combining radiotherapy and chemotherapy, particularly the timing, are analyzed to define optimal schedules for a definite therapeutic gain.

Clinical and serologic markers of stage and prognosis in small cell lung cancer. A multivariate analysis

The respective pretreatment prognostic impacts of the following markers were evaluated in 125 patients with small cell lung cancer (SCLC): lactic dehydrogenase (LDH), serum thymidine kinase (S-TK), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and tissue polypeptide antigen (TPA). More traditional clinical and serologic markers were also evaluated. Univariate analysis showed that all of the biochemical markers mentioned above, the Karnofsky index (KI) and the patient's sex were related to both the stage of disease (limited/extensive disease: LD/ED) and to survival. The strongest marker for the clinical stage was S-TK, whereas TPA showed the strongest relationship with survival. Multivariate analyses produced a model consisting of S-TK, CEA, NSE, and the patient's sex for determining the clinical stage. To compare the prognostic capacity of easily determined biochemical and simple clinical variables to the more resource-demanding variable of the clinical stage, three multivariate analyses in relation to survival were performed: (1) biochemical markers and simple clinical variables; (2) LD/ED and simple clinical variables; and (3) all available variables. The model obtained from the first analysis included TPA, KI, age, and the patient's sex; the model from the second analyses included LD/ED, patient's age, and KI; and the model from the third analysis, TPA, KI, age, sex, and LD/ED. Indices based on these three multivariate models were calculated for each patient and the prognostic capacity of these indices was compared. Pretreatment serum marker levels also had the capacity to predict both the grade and the duration of the response to therapy.

Radiotherapy by multiple fractions per day (MFD) in head and neck cancer: acute reactions of skin and mucosa

The feasibility of several unusual fractionation schedules in the radiotherapy of head and neck tumors was assessed, especially the acute reactions of skin and mucosa. All schedules were based on the principle of multiple fractions per day (MFD) leading to highly concentrated treatment series, alternating with rest periods. The fraction sizes used were between 1.6-2 Gy, overall treatment time was about 6 weeks, and total dose ranged from 60 to 67.2 Gy. The most important parameter that was modified was the size of the dose given in one treatment series. The first schedule consisted of two unequal radiation series: 48 Gy/12 days, followed by a second series of 19.2 Gy/4 days after a 3- to 4-week interval. All subsequent treatment schedules were divided in equal series: the first in 2 times 30 Gy, the second in 3 times 22.4 Gy, and the third in 4 times 16 Gy. Comparison of acute reactions in skin and mucosa after these irradiations to different dose levels has made it possible to obtain a precise idea of the time course in the development of radiation induced damage and of the dose-effect relationship. Such dose-response curves will be extremely useful in further studies on the dose-modifying effects of sensitizers and cytostatic drugs. Conclusions of this study: 1. In human oral mucosa, the threshold dose for the development of confluent mucositis (patches of 0.5 cm) after fractionated irradiation appears to be around 20 Gy. 2. Intervals of 12 days allow full repair of mucosa damage after a dose of about 20 Gy and repeating the irradiation leads to an identical reaction after second, third or fourth treatments, demonstrating that no cumulative effect exists for acute damage. This phenomenon could be exploited to reduce the acute side effects in radiotherapy. 3. The reactions observed in skin are less pronounced than those of mucosa, possibly due to the dose distribution of high energy photons. The changes are, however, slower to develop and intervals of 2 weeks are insufficient for the skin to fully recover from the radiation damage. Subsequent treatment series led to a cumulative reaction pattern. 4. Finally, a number of treatments were associated with misonidazole, an anoxic cell sensitizer, which did not appear to modify significantly the radiation reactions in either skin or mucosa.

Local failure in patients treated with radiotherapy and multidrug chemotherapy for small cell lung cancer

Fifty-three patients with small cell carcinoma of the lung were treated with chemotherapy and radiotherapy, 40 Gy in the chest tumour. Intrathoracic failure occurred in 89% of the cases with extensive disease and in 60% of those with limited disease. Since 86% of all failures were localized within the target volume, one can conclude that in most cases the radiation dose was too low for eradication of the tumour. The treatment technique resulted in dose inhomogeneities of more than +/- 5% in 45% of the cases. The high local failure rate might indicate the need of improved radiotherapy, in the first place higher radiation dose. However, 82% of the patients with limited disease and local failure and 50% of those without local failure also developed distant metastases. This might indicate that the curative potential of improved thoracic radiotherapy probably is limited. Besides, lethal treatment toxicity affected particularly patients in whom local cure had been achieved, indicating the difficulty of increasing the treatment intensity without increasing the lethal toxicity in potentially curable cases.