The effect of dose of thoracic irradiation on recurrence in patients with limited stage small cell lung cancer. Initial results of a Canadian Multicenter Randomized Trial

[Prevention, Diagnosis, Therapy, and Follow-up of Lung Cancer - Interdisciplinary Guideline of the German Respiratory Society and the German Cancer Society - Abridged Version]

The current S3 Lung Cancer Guidelines are edited with fundamental changes to the previous edition based on the dynamic influx of information to this field:The recommendations include de novo a mandatory case presentation for all patients with lung cancer in a multidisciplinary tumor board before initiation of treatment, furthermore CT-Screening for asymptomatic patients at risk (after federal approval), recommendations for incidental lung nodule management , molecular testing of all NSCLC independent of subtypes, EGFR-mutations in resectable early stage lung cancer in relapsed or recurrent disease, adjuvant TKI-therapy in the presence of common EGFR-mutations, adjuvant consolidation treatment with checkpoint inhibitors in resected lung cancer with PD-L1 ≥ 50%, obligatory evaluation of PD-L1-status, consolidation treatment with checkpoint inhibition after radiochemotherapy in patients with PD-L1-pos. tumor, adjuvant consolidation treatment with checkpoint inhibition in patients withPD-L1 ≥ 50% stage IIIA and treatment options in PD-L1 ≥ 50% tumors independent of PD-L1status and targeted therapy and treatment option immune chemotherapy in first line SCLC patients.Based on the current dynamic status of information in this field and the turnaround time required to implement new options, a transformation to a "living guideline" was proposed.

Limited-Stage Small-Cell Lung Cancer Treated with Early Chemo-Radiotherapy: The Impact of Effective Chemotherapy

Aims and Background

Small cell lung cancer is characterized by an aggressive clinical course and a high sensitivity to both chemotherapy and radiotherapy. We present the Florence University experience in concurrent early radio-chemotherapy in patients affected by limited-stage small cell lung cancer, with particular emphasis on treatment safety, disease outcome and prognostic factors.

Methods and Study Design

Fifty-seven patients were treated between June 2000 and February 2005. All patients underwent platinum-based chemotherapy, administered intravenously following two different regimens, for at least three cycles. Eighteen patients (31.6%) received epirubicin and ifosfamide in 3-week cycles alternating with etoposide and cisplatin, administered on day 1 to 3; 39 patients (68.4%) received etoposide and cisplatin. A total of 6 cycles were planned. Radiotherapy was administered concurrently to the first cycle of etoposide and cisplatin.

Results

Clinical stage (P = 0.036) and number of chemotherapy courses (P = 0.009) emerged as the only significant death predictors at univariate analysis. Number of chemotherapy courses persisted as a significant death predictor also at multivariate regression analysis, with a reduced death risk for 5–6 chemotherapy cycles in comparison to 3–4 cycles (hazard ratio, 0.44). At a mean follow up of 38.5 months (standard deviation, 3.24 years; range, 6–164 months), considering the best overall tumor response achieved at any time during the whole treatment period, we obtained 32 complete responses (56.1%), 23 partial responses (40.3%) and 2 stable diseases.

Conclusions

Our analysis showed that concurrent early radio-chemotherapy in limited-stage small cell lung cancer treatment represents a safe and effective approach in patients. We confirmed the relevant impact on overall survival of effective chemotherapy delivery.

Therapeutic procedure in small cell lung cancer

Small cell lung cancer (SCLC) represents 12.95% of all lung cancer diagnoses and continues to be a major clinical problem, with an aggressive clinical course and short disease-free duration after 1st line therapy. Treatment of SCLC remains challenging because of its rapid growth and development of drug resistance during the course of the disease. Chemotherapy remains the current optimal treatment and radical thoracic radiotherapy representing the best treatment option for fit patients with LD. Platinum-based chemotherapy is the treatment of choice in patients with good performance status, and the effect of cisplatin is important for concurrent chemoradiotherapy in LD cause of his radiosensitivity. Patients with progress disease after first-line chemotherapy have poor prognosis. Second-line therapy may produce a modest clinical benefit. A number of targeted agents have been investigated in LD and ED, mostly in unselected populations, with disappointing results. Prophylactic cranial irradiation (PCI) is recommended only for patients who had full response to first line chemotherapy, as target of improving overall survival and decreasing possibilities of brain metastases. New factors for target therapy are the hope for the management of this systematic disease. If we identify these targets for treatment of SCLC and overcome drug-resistance mechanisms, we will create new chemo-radiotherapy schedules for future.

A pooled analysis of limited-stage small-cell lung cancer patients treated with induction chemotherapy followed by concurrent platinum-based chemotherapy and 70 Gy daily radiotherapy: CALGB 30904

INTRODUCTION

Standard therapy for limited-stage small-cell lung cancer (L-SCLC) is concurrent chemotherapy and radiotherapy (RT) followed by prophylactic cranial radiotherapy. Although many consider the standard RT regimen to be 45 Gy in 1.5 Gy twice-daily fractions, this has failed to gain widespread acceptance. We pooled data of patients assigned to receive daily RT of 70 Gy from three, consecutive prospective Cancer and Leukemia Group B L-SCLC cancer trials and report the results here.

METHODS

All patients from consecutive Cancer and Leukemia Group B L-SCLC trials (39808, 30002, and 30206) using high-dosage daily RT with concurrent chemotherapy were included, and analyzed for toxicity, disease control, and survival. Overall survival (OS) and progression-free survival (PFS) were modeled using Cox proportional hazards models. Prognostic variables for OS-rate and PFS-rate were assessed using logistic regression model.

RESULTS

Two hundred patients were included. The median follow-up was 78 months. Grade 3 or greater esophagitis was 23%. The median OS for pooled population was 19.9 months (95% confidence interval [CI]: 16.7-22.3), and 5-year OS rate was 20% (95% CI: 16-27%). The 2-year PFS was 26% (95% CI: 21-32%). Multivariate analysis found younger age (p = 0.02; hazard ratio [HR]: 1.023; 95% CI: 21-32), and female sex (p = 0.02; HR:0.69; 95% CI: 0.50-0.94) independently associated with improved overall survival.

CONCLUSION

Two-Gy daily RT to a total dosage of 70 Gy was well tolerated with similar survival to 45 Gy (1.5 Gy twice-daily). This experience may aid practitioners decide whether high-dosage daily RT with platinum-based chemotherapy is appropriate outside of a clinical trial.

Intensity-modulated stereotactic radiotherapy for the treatment of medically inoperable patients with NSCLC stage I

The standard treatment for stage I non-small cell lung cancer (NSCLC) is lobectomy. However, a considerable number of patients are not eligible for standard lung surgery due to poor pulmonary function or comorbidities. We evaluated the efficacy and tolerability of intensity-modulated stereotactic radiotherapy (IMSRT) with moderate hypofractionation for these patients. Twelve patients were selected for IMSRT. 4D-CT planning was performed by gating CT-scanning positioning. The applied doses ranged between 10x4.5 Gy (80% ID) (N=1), 12x4.5 Gy (95% ID) (N=1) and 10x5.5 Gy (95% ID) (N=10). Long-term follow-up was performed including spirometry and CT for evaluation of local, locoregional and distant control. Even in patients with poor pulmonary function IMRST was safe and well tolerated. No severe acute adverse effects were observed. Estimated local control at 2 years was 90%. Moreover, IMSRT does not induce a significant deterioration of pulmonary function. IMRST is safe and feasible even for patients with very poor pulmonary function. The applied dose provides a high local control rate, although the biological equivalent dose (BED) is lower compared to the average of other SRT regimens. Therefore, IMRST may be an efficient alternative for all NSCLC stage I patients with contraindications to standard lobectomy especially in patients with small tumors in high-risk localisations.

The effect of bioequivalent radiation dose on survival of patients with limited-stage small-cell lung cancer

Background

To investigate the biological radiation dose-response for patients of limited-stage small-cell lung cancer (LS-SCLC) treated with high radiation dose.

Methods

Two hundred and five patients of LS-SCLC treated with sequential chemotherapy and thoracic radiotherapy with involved-field between 1997 and 2006 were reviewed retrospectively. Biologically effective dose (BED) was calculated for dose homogenization and was corrected with the factor of overall radiation time. Patients were divided into low BED group (n = 70) and high BED group (n = 135) with a cut-off of BED 57 Gy (equivalent to 60 Gy in 30 fractions over 40 days). Outcomes of the two groups were compared.

Results

Median follow-up was 20.7 months for all analyzable patients and 50.8 months for surviving patients. Considering all patients, median survival was 22.9 months (95% confidence interval, 20.6-25.2 months); 2- and 5-year survival rates were 47.2% and 22.3%, respectively. Patients in high BED group had a significantly better local control (p = 0.024), progression-free survival (p = 0.006) and overall survival (p = 0.005), with a trend toward improved distant-metastasis free survival (p = 0.196). Multivariable Cox regression demonstrated that age (p = 0.003), KPS (p = 0.009), weight loss (p = 0.023), and BED (p = 0.004) were significant predictors of overall survival.

Conclusions

Our data showed that a high BED was significantly associated with favourable outcomes in the Chinese LS-SCLC population, indicating that a positive BED-response relationship still existed even in a relatively high radiation dose range.

Accelerated hyperfractionated radiotherapy and concomitant chemotherapy in small cell lung cancer limited-disease. Dose response, feasibility and outcome for patients treated in western Sweden, 1998-2004

Addition of thoracic radiation therapy (TRT) to chemotherapy (CHT) can increase overall survival in patients with small cell lung cancer limited-disease (SCLC-LD). Accelerated fractionation and early concurrent platinum-based CHT, in combination with prophylactic cranial irradiation, represent up-front treatment for this group of patients. Optimised and tailored local and systemic treatment is important. These concepts were applied when a new regional treatment programme was designed at Sahlgrenska University Hospital in 1997. The planned treatment consisted of six courses of CHT (carboplatin/etoposide) + TRT +/- prophylactic cranial irradiation (PCI). Standard TRT was prescribed at 1.5 Gy BID to a total of 60 Gy during 4 weeks, starting concomitantly with the second or third course of CHT. However, patients with large tumour burdens, poor general condition and/or poor lung function received 45 Gy, 1.5 Gy BID, during 3 weeks. PCI in 15 fractions to a total dose of 30 Gy was administered to all patients with complete remission (CR) and "good" partial remission (PR) at response evaluation. Eighty consecutive patients were treated between January 1998 and December 2004. Forty-six patients were given 60 Gy and 34 patients 45 Gy. Acute toxicity occurred as esophagitis grade III (RTOG/EORTC) in 16% and as pneumonitis grade I-II in 10%. There were no differences in toxicity between the two groups. Three- and five-year overall survival was 25% and 16%, respectively. Medica survival was 20.8 months with no significant difference between the two groups. In conclusion, TRT with a total dose of 60 to 45 Gy is feasible with comparable toxicity and no difference in local control or survival. Distant metastasis is the main cause of death in this disease; the future challenge is thus further improvement of the systemic therapy combines with optimised local TRT.

A phase II study of paclitaxel + etoposide + cisplatin + concurrent radiation therapy for previously untreated limited stage small cell lung cancer (E2596): a trial of the Eastern Cooperative Oncology Group

INTRODUCTION

To determine the 1-year survival, response rate, and toxicity for patients with limited stage small cell lung cancer treated with the combination of cisplatin plus etoposide plus paclitaxel with delayed concurrent (starting with cycle 3) high dose thoracic radiotherapy.

PATIENTS AND METHODS

Patients with previously untreated limited stage small cell lung cancer, Easter Cooperative Oncology Group performance status of 0-2 and adequate organ function were eligible. Cycles 1 and 2 of chemotherapy consisted of paclitaxel 170 mg/m intravenous day 1, etoposide 80 mg/m intravenous days 1 to 3, and cisplatin 60 mg/m intravenous day 1 followed by filgrastim 5 microg/kg subcutaneously days 4 to 13. Cycles 3 and 4 of chemotherapy consisted of a reduced dose of paclitaxel 135 mg/m intravenous day 1, and the same dose of etoposide and cisplatin with concurrent thoracic radiation therapy 1.8 Gy in 35 fractions (total 63 Gy) administered over 7 weeks.

RESULTS

Sixty-three patients were entered, 61 patients were eligible. The most common grade 4 toxicity seen was granulocytopenia (62%). Nonhematologic toxicities included febrile neutropenia in 19% of patients, grade 3 and 4 esophagitis in 32% of patients, and grade 3 peripheral neuropathy in 14% of patients. Two patients suffered lethal toxicities. The overall response rate was 79%. The 1-year survival rate was 64%. The median overall survival was 15.7 months, and the median progression-free survival was 8.6 months.

CONCLUSIONS

The combination of cisplatin plus etoposide plus paclitaxel chemotherapy and concurrent delayed thoracic radiotherapy as administered in this trial provide no apparent advantage with respect to response, local control, or survival compared with historical controls.

Limited-Stage Extrapulmonary Small Cell Carcinoma: Outcomes After Modern Chemotherapy and Radiotherapy

BACKGROUND

The purpose of this study was to determine the clinical outcomes and patterns of failure of limited-stage extrapulmonary small cell carcinoma (EPSCC) treated with modern chemotherapy and radiation (RT).

METHODS

We retrospectively identified 18 patients with limited-stage EPSCC treated definitively with three-dimensional conformal RT or intensity modulated radiation therapy and chemotherapy. Patients were treated between November 1987 and May 2006. Primary sites of disease included head and neck (n = 7), genitourinary (n = 7), gynecologic (n = 3), and gastrointestinal (n = 1). Chemotherapy consisted of combined platinum and etoposide in 88% of patients. The median number of chemotherapy cycles was 4 (range 3-6), and the median RT dose was 62 Gy (range 32.4-85 Gy). No patient received prophylactic cranial radiation.

RESULTS

With a median follow-up for all patients of 14 months (range 4-42 months), the median overall survival was 17 months, and median disease-free survival was 6 months. Eleven percent (2 of 18) of patients had a locoregional failure, and 78% (14 of 18) had a distant failure. One of these patients had a brain failure. There were no significant differences between the overall survival for patients with gynecologic, head and neck, and genitourinary disease.

CONCLUSIONS

Despite modern chemotherapy and RT, patients with limited-stage EPSCC do poorly. Consistent with previous findings the majority of the first failures are distant. Brain failures in this series were uncommon despite no prophylactic cranial radiation. These findings support the need for further studies in an attempt to improve systemic therapies for this disease.

Phase I study of hypofractionated dose-escalated thoracic radiotherapy for limited-stage small-cell lung cancer

PURPOSE

To determine the maximal tolerated dose of hypofractionated thoracic radiotherapy with concurrent chemotherapy for limited-stage small-cell lung cancer patients.

METHODS AND MATERIALS

Three radiotherapy regimens were used. Radiotherapy was given in two phases: patients initially received 20 Gy in 10 fractions to gross tumor plus uninvolved mediastinal nodes, followed by a boost to gross disease of 30, 38, or 42 Gy in 15 fractions. Radiotherapy was planned with conformal techniques. All patients received four cycles of cisplatin (25 mg/m2) and etoposide (100 mg/m2) chemotherapy. Radiotherapy commenced with Day 1 of Cycle 2 of chemotherapy. All complete/near-complete responders were offered prophylactic cranial irradiation. The maximal tolerated dose of radiotherapy was based on the dose that caused unacceptably high rates of radiotherapy-related toxicity.

RESULTS

Thirteen patients were accrued. All patients who commenced radiotherapy received all prescribed chemo- and radiotherapy. There were no treatment-related deaths. There was one Grade 3 acute nonhematologic toxicity in the 50-Gy group. Of the 6 patients given 58 Gy, 3 experienced acute Grade 3 esophagitis. With a median follow-up of 7 months, median overall survival was 9.5 months.

CONCLUSIONS

The maximal tolerated dose of thoracic radiotherapy with concurrent chemotherapy on this trial was 50 Gy in 25 daily fractions.

The Role of Radiation Therapy in Thoracic Tumors

Radiation plays an important role in the treatment of thoracic tumors. During the last 10 years there have been several major advances in thoracic RT including the incorporation of concurrent chemotherapy and the application of con-formal radiation-delivery techniques (eg, stereotactic RT, three-dimensional conformal RT, and intensity-modulated RT) that allow radiation dose escalation. Radiation as a local measure remains the definitive treatment of medically inoperable or surgically unresectable disease in NSCLC and part of a multimodality regimen for locally advanced NSCLC, limited stage SCLC, esophageal cancer, thymoma, and mesothelioma.

Thoracic radiation therapy for limited-stage small-cell lung cancer: unanswered questions

The role of thoracic radiation therapy (RT; TRT) is now established in the management of limited-stage small-cell lung cancer (SCLC). There is increasing evidence in the literature in favor of early concurrent chemoradiation therapy, and a gold standard of care for patients with a good performance status is twice-daily TRT (45 Gy in 3 weeks) with concurrent cisplatin/etoposide. Five-year survival rates > 20% can be expected with this combined-modality approach. Although current clinical trials are exploring the efficacy of new chemotherapeutic strategies for the disease, essential questions related to the optimization of TRT remain unanswered. In particular, the optimal RT dose, fractionation, and treatment volume have not been defined. This review highlights the need for well-designed multinational trials aimed at the optimization and standardization of RT for limited-stage SCLC. These trials should integrate translational research studies to investigate the molecular basis of RT resistance and to develop biomarker profiles of prognosis.

Thoracic Radiotherapy for Limited-stage Small-cell Lung Cancer: Controversies and Future developments

Thoracic radiotherapy has an established role in the management of limited-disease small-cell lung cancer (LD SCLC). However, essential questions relating to the optimisation of thoracic radiotherapy remain unanswered, including volume of irradiation, optimal total dose, fractionation, timing and sequencing of radiation. This review highlights the need for well-designed multi-national trials aimed at the optimisation and standardisation of radiotherapy for LD SCLC.

Combined Chemoradiotherapy in Small Cell Lung Cancer

Combined chemoradiotherapy is the established standard of care for limited stage small cell lung cancer; it provides cure in 15% to 25% of patients. Early concurrent therapy imparts a 5% long-term survival benefit compared with sequential therapy. Hyperfractionated delivery of radiotherapy may provide a small incremental benefit when compared with standard fractionation. Radiotherapy dose escalation and reduced radiotherapy volumes are feasible; however, survival benefit has not been confirmed. Cisplatin and etoposide remain the preferred chemotherapy agents. New chemotherapeutic agents and novel treatment approaches are under intense investigation.

Recent advances in management of small-cell lung cancer

Small-cell lung cancer (SCLC) is a smoking-related disease with a poor prognosis. While SCLC is usually initially sensitive to chemotherapy and radiotherapy, responses are rarely long lasting. Frustratingly, most patients ultimately relapse, often with increasingly treatment resistant disease. Many strategies have been developed in an attempt to improve treatment outcomes, which have plateaued since the introduction of combination chemotherapy in the 1980s. These include trials of maintenance therapy, and dose intensification, the latter by means of increasing dose density, growth factor support and high dose chemotherapy with autologous stem cell rescue. None have been shown to improve patient survival. On the other hand, the integration of concurrent thoracic radiation and prophylactic cranial irradiation has improved the survival outcomes in patients with limited disease. In extensive disease, irinotecan combined with cisplatin has shown promise in improving survival over conventional platinum/etoposide chemotherapy schedules and a confirmatory study is awaited. The future of SCLC treatment may however lie with molecularly targeted therapies, such as antiangiogenesis agents and signal transduction inhibitors, which are being studied at present.

Radiation dose intensification in limited-stage small-cell lung cancer

Multiple studies have confirmed the value of radiation therapy in limited-stage small-cell lung cancer. The appropriate dose of radiation and the optimal fractionation scheme, however, remain controversial. This article will examine the history of radiation therapy in the management of small-cell lung cancer. It will review the rationale for the various approaches to radiation dose intensification, and review the results of important trials investigating the issue of radiation dose in the management of this disease. Survival outcomes and toxicity of various approaches to radiation dose intensification, including dose escalation and hyperfractionation, will be assessed. The implications of advancements in technology will be examined, and the optimal design of future trials will be discussed.

Radiation dose escalation in limited-stage small-cell lung cancer

PURPOSE

To review the treatment outcomes of limited-stage small-cell lung cancer (LS-SCLC) patients treated with > or =50 Gy of radiation at Massachusetts General Hospital (MGH) between 1987 and 2000 and to assess for evidence of a continuation of a radiation dose response.

METHODS AND MATERIALS

The MGH cancer registry was searched for SCLC patients treated with radiotherapy between 1987 and 2000. Records of LS-SCLC patients treated with curative intent and radiation doses > or =50 Gy at MGH were reviewed. Surgical patients were excluded.

RESULTS

Eighty-four LS-SCLC patients were treated with radiotherapy at MGH between 1987 and 2000. Of the 84 patients, 54 (64%) met the inclusion criteria; 30 patients (56%) in this study died, and 4 (7%) were lost to follow-up. The median follow-up of the surviving patients was 42 months. The median overall survival was 29 months. The 2- and 5-year survival rate was 64% and 47%, respectively. The local control rate at 3 years was 78%.

CONCLUSION

The overall survival, local control, and disease-free survival rates for LS-SCLC patients treated with > or =50 Gy of radiation compare favorably with historical data. These findings suggest a continuation of the radiation dose-response curve in LS-SCLC. This further supports the need for appropriately powered, Phase III, prospective randomized trials in radiation dose escalation or radiation dose intensification for LS-SCLC.

Thoracic radiotherapy for limited-stage small cell lung cancer: issues of timing, volumes, dose, and fractionation

Although meta-analysis of randomized trials comparing chemotherapy alone versus chemotherapy plus thoracic irradiation demonstrated that thoracic radiotherapy reduced mortality by 14%, this analysis probably underestimates the effect of optimally delivered thoracic irradiation integrated with appropriate chemotherapy. However, there remains much debate as to the optimal timing of the radiotherapy and the radiotherapy volume, dose, and fractionation. Theoretically, early use of radiotherapy should reduce the probability of chemotherapy and radiation resistance, accelerated repopulation, and metastatic events. Deferred or sequential radiotherapy potentially allows smaller radiotherapy fields. Of the seven randomized controlled trials examining timing, only those with early chemoradiation have 5-year survival rates in excess of 20%. The "chemoradiation package" can be defined as the time from the start of chemotherapy until the completion of radiotherapy. The best median survival and long-term survival rates have been observed in trials with a chemoradiation package time of less than 6 weeks. Protocols combining chemotherapy and radiotherapy must respect radiobiologic principles concerning the time factor derived from radiotherapy fractionation studies.

Long-term results of induction chemotherapy followed by concurrent chemotherapy and thoracic irradiation in limited small cell lung cancer

BACKGROUND

Small cell lung cancer (SCLC) is a chemoresponsive tumor but overall survival remains poor even in limited disease (LD). With the aim of eradicating chemoresistant tumor cells and reducing toxicity, we investigated in this phase II trial the feasibility and outcome of a sequential approach of induction chemotherapy (CT) followed, in responding patients with LD-SCLC, by intensified platinum-based CT and concurrent thoracic irradiation (TI).

MATERIALS AND METHODS

We treated 55 consecutive LD-SCLC patients with three 21-day cycles of cyclophosphamide, epiadriamycin and vincristine (CEV) as induction CT. In 44 (80%) patients there was an objective response and they received treatment intensification consisting of TI and concomitant CT with carboplatin and etoposide plus recombinant granulocite colony stimulating factor. Twenty-five (57%) patients were submitted to twice-daily thoracic irradiation (TDTI; 1.5 Gy per fraction, to a total dose of 45 Gy) and 19 (43%) to once-daily thoracic irradiation (ODTI; 2 Gy per fraction, to a total dose of 50 Gy).

RESULTS

Median follow up was 75 months (range, 42-102). Of 44 patients submitted to intensification with TI plus CT, 32 (73%) had a complete and 12 (27%) a partial response. Median overall survival of all 55 patients was 17 months with actuarial survival probabilities of 2 and 5 years, 32 and 25%, respectively. Analysis of patient sub-groups showed a 5-month median survival in non-responders, 19 in TDTI and 17 in ODTI patients, respectively. Two and 5 year survival probabilities were 0% in non-responders, 40 and 35% in TDTI and 39 and 21% in ODTI patients, respectively. At present, 13 of 44 responders are still alive, of which nine (20%) have been progression-free from 45 to 93 months (median 60). Treatment failure was registered in 31 (70%) of 44 patients who received both induction and intensification treatment. One-half of patients had intrathoracic recurrence, eight of which only local and the remaining seven local and distant. Fourteen (32%) patients had brain metastases. Grade 3-4 neutropenia occurred in 24 (55%) patients with no differences between treatment groups. Grade 3 esophagitis was registered in four (9%) patients: in 3/25 (12%) and 1/19 (5%) of those who received TDTI and ODTI, respectively (P=not significant). Acute radiation pneumonitis occurred in three (12%) patients submitted to TDTI. No clinically debilitating pulmonary fibrosis, permanent esophageal stricture or toxic death was observed.

CONCLUSIONS

In LD-SCLC patients late concurrent CT plus TI is feasible and effective. Our long-term results are similar to the best reported in the literature. Despite the high incidence of complete response obtained, however, one-half of the patients had intrathoracic relapse and one-third brain metastases.

Long-term Results of a Phase I/II Study of High-Dose Thoracic Radiotherapy With Concomitant Cisplatin and Etoposide in Limited Stage Small-Cell Lung Cancer

This report presents the results from a Mayo Clinic initiated phase I/II study exploring a potentially more aggressive local and systemic approach for treatment of limited-stage small-cell lung cancer (LSSCLC). Five patients with LSSCLC received three cycles of induction cyclophosphamide, etoposide, and infusion cisplatin chemotherapy. This was followed by accelerated hyperfractionated thoracic radiotherapy (AHFTRT) consisting of 30 Gy given as 1.5-Gy fractions twice daily with a 2-week break and then the AHFTRT was repeated. The AHFTRT was given concomitantly with daily oral etoposide and daily intravenous cisplatin. Prophylactic cranial radiation was delivered with the AHFTRT. After completion of the AHFTRT, patients received 4 cycles of oral etoposide maintenance chemotherapy. Follow-up of patients was continued until death or a minimum of 42 months. Three patients had severe toxic responses. No patients completed the entire protocol because of toxicity or progression during treatment. Three patients completed the majority of the protocol except for the four cycles of maintenance etoposide. Four of five patients achieved a complete response. There were two recurrences within the irradiated field, and distant metastases developed in four patients. Acute nonlymphocytic leukemia developed in one patient, who died 2 months later. No patient completed the entire protocol, because of toxicity or progression; therefore, this protocol cannot be recommended for the treatment of LSSCLC.

Chest radiotherapy in limited-stage small cell lung cancer: facts, questions, prospects

OBJECTIVE AND STUDY DESIGN

Limited-disease small cell lung cancer (LD-SCLC) is initially very sensitive to both radiotherapy and chemotherapy. However, the 5-year survival is generally only 10-15%, with most patients failing with therapy refractory relapses, both locally and in distant sites. The addition of chest irradiation to chemotherapy increases the absolute survival by approximately 5%. We reviewed the many controversies regarding optimal timing and irradiation technique.

RESULTS

No strong data support total radiation doses over 50 Gy. According to one phase III trial and several retrospective studies, increasing the volume of the radiation fields to the pre-chemotherapy tumour volume instead of the post-chemotherapy volume does not improve local control.

CONCLUSIONS

The total time in which the entire combined-modality treatment is delivered may be important. From seven randomized trials, it can be concluded that the timing of the radiotherapy as such is not very important. Some phase III trials support the use of accelerated chest radiation together with cisplatin-etoposide chemotherapy, delivered from the first day of treatment, although no firm conclusions can be drawn from the available data. The best results are reported in studies in which the time from the start of treatment to the end of the radiotherapy was less than 30 days. This has to be taken into consideration when treatment modalities incorporating new chemotherapeutic agents and radiotherapy are considered.

Small-Cell Lung Cancer at the Millennium: Radiotherapy Innovations Improve Survival While New Chemotherapy Treatments Remain Unproven

Because of the systemic nature of small-cell lung cancer, one could predict that treatment advances would mainly come from innovations of chemotherapy. Although combination chemotherapy is better than monotherapy, a clearly superior multidrug regimen has not emerged. Investigations of more intensive chemotherapy with increased drug diversity and delivery have not prospered, and advantages of regimens including new agents have not yet been demonstrated in controlled trials. As we enter the new millennium, twenty-five years have passed since the publication of studies describing the combined used of cyclophosphamide, doxorubicin, and vincristine for small-cell lung cancer. It has been almost 20 years since the publication of the combination of etoposide and cisplatin became the widely accepted standard for the treatment of small-cell lung cancer. Today, both treatment regimens continue to be widely used as standard therapy. Ironically, proven advances in this systemic disease have been associated with innovations of local therapy. Data from limited-stage small-cell lung cancer clinical trials published during the 1990s demonstrated that a number of radiotherapy interventions had significant survival benefits. These radiotherapy interventions include addition of thoracic irradiation to chemotherapy, early delivery of thoracic irradiation concurrently with chemotherapy, more intense thoracic irradiation, and prophylactic cranial irradiation. As we await improved systemic therapy in the next millennium, the prognosis for extensive-stage disease remains guarded, and adherence to optimal radiotherapy detail remains crucial for routine management of limited-stage patients.

[Discussion on the role of radiotherapy in non-small cell lung cancer apropos of 137 non-metastatic cases]

PURPOSE

Retrospective analysis of 137 patients with limited stage small cell lung carcinoma who received radiotherapy between 1978 and 1990 and literature review.

MATERIALS AND METHODS

The population was divided into two groups according to the total dose of radiation delivered to the thorax: 45 Gy (1.8 Gy by fraction) or the equivalent irradiation dose administered by hypofractionation (group 1, 29 patients) and 65 Gy (1,8 Gy by fraction) or the equivalent irradiation dose administered by hypofractionation (group 2, 96 patients).

RESULTS

The actuarial survival rate was 20% at 2 years and 9% at 5 years. It was 25% at 2 years and 17% at 5 years for 12 patients with surgical resection. For patients who did not undergo surgical resection, it was 20% at 2 years and 9% at 5 years for 96 patients belonging to group 2, while it was 14% at 2 years and 3.5% at 5 years for group 1. Deaths due to local relapse reached 48% in the group treated with 45 Gy and 33% in the group treated with 65 Gy (NS). For the 33 patients who were more than 70 years old at the time of treatment, the actuarial survival rate was 18% at 2 years and 6% at 5 years with death from other causes twice as high as that of patients who were less than 70 years old at the time of treatment. For the 59 patients who were less than 70 years old at the time of treatment, in whom supraclavicular node, pleural effusion or superior vena cava syndrome were not depicted and who were treated with the highest dose (4% of the total number of patients), the actuarial survival rate was 20% at 2 years and 14% at 5 years. Literature analysis shows that treatment of limited small cell lung cancer with chemotherapy and thoracic irradiation increased the overall survival rate from 16.5% to 23% at 2 years and the local control from 23% to 48%, in comparison with chemotherapy alone.

CONCLUSION

Although these results are modest, they seem to be improved with more effective chemotherapy, especially with the association of radiotherapy and concomitant chemotherapy.

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.

Thoracic and cranial radiotherapy for limited-stage small cell lung cancer

Chemotherapy remains the mainstay of treatment for small cell lung cancer (SCLC). For patients with limited-stage disease, the addition of thoracic radiotherapy confers a moderate improvement in local control and a modest survival benefit, but these improvements come at the cost of increased toxic reactions. The optimal method for integrating chemotherapy and thoracic radiotherapy is unresolved. Concurrent and alternating strategies are appealing because they allow uninterrupted delivery of chemotherapy, but they have not been proven to be superior to conventional sequential approaches. Based on limited data, delivery of thoracic radiation early in the treatment course may be preferable to delivery later in the course. There is evidence of a radiation dose-response effect for SCLC, and, in standard regimens, thoracic radiation doses in the range of 50 to 60 Gy are recommended. The use of limited radiation fields (to postchemotherapy tumor volumes) appears reasonable. Results for alternative thoracic radiation fractionation schedules such as accelerated hyperfractionation are promising and worthy of further investigation. The role of prophylactic cranial irradiation (PCI) is controversial and should be individualized. It should be considered for the favorable subgroup of patients with limited-stage disease who achieve a complete response to chemotherapy and thoracic radiotherapy. If given, we recommend a total dose of 30 to 36 Gy in 2-Gy fractions; PCI should not be delivered concomitantly with chemotherapy.

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)

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.

Twice daily thoracic irradiation for limited small cell lung cancer

Thoracic failure is a significant obstacle to the cure of limited stage small-cell lung cancer (LSCLC) patients treated with combined modality therapy. In 1985 we initiated a prospective trial to evaluate the impact of twice daily thoracic irradiation without concomitant chemotherapy on control of intrathoracic tumor in LSCLC. Twenty-nine patients treated in this fashion were compared with 36 patients treated from 1979-1982 with once daily thoracic irradiation and concomitant chemotherapy. Both groups received the same induction chemotherapy; cyclophosphamide, Adriamycin, and vincristine (CAV) alternating with cisplatin and etoposide. For consolidation, the twice daily patients received thoracic irradiation, 45 Gy in 1.5 Gy fractions given twice daily, and the once daily patients received thoracic irradiation, 45 Gy in 2.5 Gy fractions given once daily with concomitant cyclophosphamide and vincristine. After completion of radiotherapy both groups received maintenance chemotherapy. The complete response (CR) rate after thoracic irradiation was higher for twice daily patients (86% (25/29) compared to the once daily patients [61% (22/36), p = 0.02]. However, this advantage was offset by the shorter duration of thoracic control among CR patients treated with twice daily thoracic irradiation compared to once daily thoracic irradiation (32% vs 67% at 2 years, p less than 0.05). In view of the enhanced initial response of LSCLC to twice daily thoracic irradiation, this basic radiotherapeutic approach seems appropriate, but new strategies using higher doses of twice daily thoracic irradiation or concomitant chemotherapy appear to be necessary to enhance long-term thoracic control.

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.

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)

Pitfalls in the use of high energy X rays to treat tumors in the lung

The problem of central axis dose reduction for high energy photon beams of small cross-sectional area traversing normal lung tissue is well known. An additional problem, which may be not as well appreciated, is the loss of electronic equilibrium on the periphery of high energy photon beams, resulting in an increase in the penumbra occurring in lung. We have compared profiles of x-ray beams ranging in energy from 4 MV to 18 MV. The profiles were measured at 10-cm depth in unit-density and lung-density (0.26) phantoms. At the highest energy the 20% to 80% physical penumbra width was measured to be 7.5 mm in the unit-density material, whereas in the lung phantom the width was 18 mm. At 4 MV the situation was reversed; that is, the penumbra was slightly smaller in the lung phantom. Most computer programs for radiation therapy treatment planning do not take into account this change in beam profile when calculating dose in the lung. As a result, unanticipated underdosing inside the field and greater dose outside the field can occur when high-energy X rays are used.