Phase I study of twice-weekly gemcitabine and concurrent thoracic radiation for patients with locally advanced non-small-cell lung cancer

Radiation-Induced Lung Injury (RILI)

Radiation pneumonitis (RP) and radiation fibrosis (RF) are two dose-limiting toxicities of radiotherapy (RT), especially for lung, and esophageal cancer. It occurs in 5-20% of patients and limits the maximum dose that can be delivered, reducing tumor control probability (TCP) and may lead to dyspnea, lung fibrosis, and impaired quality of life. Both physical and biological factors determine the normal tissue complication probability (NTCP) by Radiotherapy. A better understanding of the pathophysiological sequence of radiation-induced lung injury (RILI) and the intrinsic, environmental and treatment-related factors may aid in the prevention, and better management of radiation-induced lung damage. In this review, we summarize our current understanding of the pathological and molecular consequences of lung exposure to ionizing radiation, and pharmaceutical interventions that may be beneficial in the prevention or curtailment of RILI, and therefore enable a more durable therapeutic tumor response.

Dose Escalation Study of Concurrent Chemoradiotherapy With the Use of Involved-field Conformal Radiotherapy and Accelerated Hyperfractionation in Combination With Cisplatin and Vinorelbine Chemotherapy for Stage III Non-small Cell Lung Cancer: The Final Report

OBJECTIVES

A phase I study to determine a recommended dose of thoracic radiotherapy using accelerated hyperfractionation for unresectable non-small cell lung cancer was conducted.

MATERIALS AND METHODS

We used chemotherapy of a cisplatin doublet and 2 dose levels of radiation with accelerated hyperfractionation. The radiation dose levels were: a total dose of 60 Gy in 40 fractions at level 1, and 66 Gy in 44 fractions at level 2. Eligible patients with unresectable stage III non-small cell lung cancer received cisplatin and vinorelbine. Radiation therapy started on day 2 of chemotherapy and was delivered twice daily for 5 days a week.

RESULTS

Total 12 patients were enrolled, with 6 patients each at dose levels 1 and 2. Dose-limiting toxicity was noted in 2 patients at level 1; one patient had grade 3 febrile neutropenia and the other patient had grade 3 esophagitis. No dose-limiting toxicity was noted in the 6 patients at level 2. Grade 3 to 4 leukopenia, neutropenia, and anemia were noted in 11 (92%), 9 (75%), and 8 (67%) of the total 12 patients, respectively. Grade 3 anorexia and infection were noted in 2 patients (17%) at each level. Grade 3 nausea, fatigue, esophagitis, and febrile neutropenia were noted in 1 patient (8%) at each level. The response rate in the total 12 patients was 83.3%. The median progression-free survival time and the median overall survival time were 10.7 and 24.2 months, respectively.

CONCLUSIONS

Sixty-six gray in 44 fractions is the recommended dose for the following phase II study.

Cisplatin: process and future

One of the most important anticancer agents is cisplatin (CDDP). Numerous studies with a CDDP-based combination have been reported over the last 30 years. The use of CDDP in the 1980s and 1990s showed responses in advanced stage non-small-cell lung cancer (NSCLC). Over the years it was found that the side effects of this agent (particularly nephrotoxicity) were a common problem. Agents such as carboplatin, taxanes, gemcitabine, irinotecan and pemetrexed proved to be effective in NSCLC with reduced or no nephrotoxicity. The administration of these newer agents improved several side effects, but without improving efficacy. When prophylactic (adjuvant) treatment for NSCLC was introduced, CDDP was the agent selected, which indicated the value of the drug. Recently, a novel formulation of CDDP, liposomal cisplatin, which has shown very low toxicity, no nephrotoxicity and equal effectiveness was produced; its importance is its higher effectiveness than standard CDDP in lung adenocarcinoma.

Weekly paclitaxel, gemcitabine, and external irradiation followed by randomized farnesyl transferase inhibitor R115777 for locally advanced pancreatic cancer

PURPOSE

The Radiation Therapy Oncology Group (RTOG) multi-institutional Phase II study 98-12, evaluating paclitaxel and concurrent radiation (RT) for locally advanced pancreatic cancer, demonstrated a median survival of 11.3 months and a 1-year survival of 43%. The purpose of the randomized Phase II study by RTOG 0020 was to evaluate the addition of weekly low- dose gemcitabine with concurrent paclitaxel/RT and to evaluate the efficacy and safety of the farnesyl transferase inhibitor R115777 following chemoradiation.

PATIENTS AND METHODS

Patients with unresectable, nonmetastatic adenocarcinoma of the pancreas were eligible. Patients in Arm 1 received gemcitabine, 75 mg/m(2)/week, and paclitaxel, 40 mg/m(2)/week, for 6 weeks, with 50.4 Gy radiation (CXRT). Patients in Arm 2 received an identical chemoradiation regimen but then received maintenance R115777, 300 mg twice a day for 21 days every 28 days (CXRT+R115777), until disease progression or unacceptable toxicity.

RESULTS

One hundred ninety-five patients were entered into this study, and 184 were analyzable. Grade 4 nonhematologic toxicities occurred in less than 5% of CXRT patients. The most common grade 3/4 toxicity from R115777 was myelosuppression; however, grade 3/4 hepatic, metabolic, musculoskeletal, and neurologic toxicities were also reported. The median survival time was 11.5 months and 8.9 months for the CXRT and CXRT+R115777 arms, respectively.

CONCLUSIONS

The CXRT arm achieved a median survival of almost 1-year, supporting chemoradiation as an important therapeutic modality for locally advanced pancreatic cancer. Maintenance R115777 is not effective and is associated with a broad range of toxicities. These findings provide clinical evidence that inhibition of farnesylation affects many metabolic pathways, underscoring the challenge of developing an effective K-ras inhibitor.

The optimal chemotherapy for stage III non-small cell lung cancer patients

Nearly one third of non-small cell lung cancer (NSCLC) patients at diagnosis have stage III disease. Concurrent chemoradiation has emerged as the standard of care for patients with unresectable stage III NSCLC. Meta-analyses of studies comparing concurrent with sequential therapy showed that there was a relative improvement of about 20% with concurrent therapy over sequential therapy in these patients and that concurrent chemoradiation is more toxic than the sequential approach, particularly with regard to esophagitis. The incidence of pneumonitis is not significantly higher with concurrent therapy. All the phase 3 trials comparing concurrent with sequential therapy included cisplatin-based therapy. In addition, patients enrolled in these studies were required to have good performance status and some studies mandated limited weight loss. Some patients are also treated with lower doses of chemotherapy, particularly carboplatin and paclitaxel, concurrently with radiation followed by full-dose chemotherapy. Randomized studies have failed to show benefit of induction or consolidation chemotherapy. For patients who have a poor performance status or significant weight loss, a sequential approach of chemotherapy followed by radiation may be appropriate. Ongoing clinical trials are evaluating the utility of integrating some of the newer agents such as pemetrexed and cetuximab into the treatment plan for stage III patients.

Phase II study of pemetrexed and cisplatin, with chest radiotherapy followed by docetaxel in patients with stage III non-small cell lung cancer

BACKGROUND

Pemetrexed has emerged as one of the most active agents for the treatment of patients with advanced non-small cell lung cancer (NSCLC). We conducted a phase II study to assess the efficacy and feasibility of integrating pemetrexed in a concurrent therapy plan for patients with stage III NSCLC.

METHODS

Patients with stage III NSCLC with performance status 0 to 1, adequate organ function including pulmonary function, and V20 less than 40% were eligible. Patients were treated with cisplatin 75 mg/m² (first five patients 60 mg/m²) and pemetrexed 500 mg/m² every 21 days for three cycles with chest radiotherapy to 66 Gy. Patients then received three cycles of docetaxel 75 mg/m² every 21 days. Tumors were analyzed for Excision Repair Cross Complementation Group 1 and thymidylate synthase.

RESULTS

Patient characteristics (N = 28) were median age, 60; males, 68%; stage IIIB, 64%; and squamous cell, 43%. Twenty-four patients (86%) completed all three cycles of cisplatin/pemetrexed. Of the 24 patients eligible for docetaxel, 21 (87%) received it. Grade 3/4 toxicities were neutropenia (39%), febrile neutropenia (14%), esophagitis (14%), and pneumonitis (4%). Median survival was 34 months, and 1-year survival was 66%. Survival was not significantly different in squamous and other histology patients. Tumor analysis in 16 patients showed that moderate/strong expression of thymidylate synthase was significantly associated with progression-free survival and overall survival.

CONCLUSION

Integrating pemetrexed in a concurrent therapy regimen for patients with stage III NSCLC is feasible and was associated with a median survival of 34 months.

Clinical perspectives on dose escalation for non-small-cell lung cancer

Lung cancer remains the leading cause of cancer death in the United States. The standard of care for patients with locally advanced non-small-cell lung cancer is radiation plus chemotherapy. The nationally accepted standard radiation prescription dose has remained at 60-63 Gy for more than 30 years, with local failure rates reaching 85% and median survival rates of approximately 17 months. With smaller treatment volumes and the increased conformality of radiation delivery, the administration of higher radiation doses to the target while minimizing dose to critical structures is feasible. Clinical outcome is improved while minimizing toxicity. Recent prospective trials escalating doses to 74 Gy with concurrent chemotherapy have demonstrated promise with improved survival rates and acceptable toxicity rates.

High frequency of radiation pneumonitis in patients with locally advanced non-small cell lung cancer treated with concurrent radiotherapy and gemcitabine after induction with gemcitabine and carboplatin

INTRODUCTION

The combination of chemotherapy and thoracic radiation is the standard treatment for locally advanced non-small cell lung cancer (NSCLC). However, most favorable chemotherapy regimen, timing of full-dose chemotherapy, and optimal combination of chemotherapy with radiation remain to be determined. Our primary objective was to evaluate the efficacy and safety of gemcitabine concurrent with radiotherapy after induction chemotherapy with gemcitabine plus carboplatin for locally advanced NSCLC.

PATIENTS AND METHODS

Patients with histologically proven NSCLC stage IIIA and -B received carboplatin (area under the curve of 2.5) and gemcitabine (800 mg/m) on days 1 and 8, every 21 days for two cycles, followed by conventional fractioned thoracic radiotherapy and concomitant weekly gemcitabine 200 mg/m, and finally, consolidation chemotherapy.

RESULTS

Inclusion was discontinued because of high-grade 3 to 5 radiation-pneumonitis events (6 of 19 patients, 31.6%), including one treatment-related death associated with radiation pneumonitis. Median follow-up was 11.9 months. Most common grades 3/4 hematological side effects comprised anemia, neutropenia 3 of 19 patients, each (15.8%), and thrombocytopenia (4 of 19, 21.1%) during induction. Partial response was observed in 10 patients (52.6%) following induction chemotherapy. After concurrent chemo-radiotherapy, overall response was 68.4%. Four patients (21.1%) underwent surgical resection. Median progression-free survival and overall survival were 12 +/- 1 month (95% confidence interval [CI], 9.8-14.1) and 21 +/- 3.5 months (95% CI, 14-27.9 months), respectively.

CONCLUSION

Concurrent radiotherapy with gemcitabine after induction with gemcitabine and carboplatin showed a high-response rate; however, it is associated with excessive pulmonary toxicity. Adjustments in gemcitabine dosage during radiotherapy or changes in radiotherapy planning could reduce toxicity.

On the path to seeking novel radiosensitizers

Radiation therapy is a highly effective cancer treatment modality, and extensive investigations have been undertaken over the years to augment its efficacy in the clinic. This review summarizes the current understanding of the biologic bases underpinning many of the clinically used radiosensitizers. In addition, this review illustrates how the advent of innovative, high-throughput technologies with integration of different disciplines could be harnessed for an expeditious discovery process for novel radiosensitizers, providing an exciting future for such pursuits in radiation biology and oncology.

Randomized phase II trial of induction chemotherapy followed by concurrent chemotherapy and dose-escalated thoracic conformal radiotherapy (74 Gy) in stage III non-small-cell lung cancer: CALGB 30105

PURPOSE

To evaluate 74 Gy thoracic radiation therapy (TRT) with induction and concurrent chemotherapy in stage IIIA/B non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Patients with stage IIIA/B NSCLC were randomly assigned to induction chemotherapy with either carboplatin (area under the curve [AUC], 6; days 1 and 22) with paclitaxel (225 mg/m(2); days 1 and 22; arm A) or carboplatin (AUC, 5; days 1 and 22) with gemcitabine (1,000 mg/m(2); days 1, 8, 22, and 29; arm B). On day 43, arm A received weekly carboplatin (AUC, 2) and paclitaxel (45 mg/m(2)) while arm B received biweekly gemcitabine (35 mg/m(2)) both delivered concurrently with 74 Gy of TRT utilizing three-dimensional treatment planning. The primary end point was survival at 18 months.

RESULTS

Forty-three and 26 patients were accrued to arms A and B, respectively. Arm B was closed prematurely due to a high rate of grade 4 to 5 pulmonary toxicity. The overall response rate was 66.6% (95% CI, 50.5% to 80.4%) and 69.2% (95% CI, 48.2% to 85.7%) on arm A and B, respectively. The median survival time (MST) and 1-year survival rate was 24.3 months (95% CI, 12.3 to 36.4) and 66.7% (95% CI, 50.3 to 78.7) and 12.5 months (95% CI, 9.4 to 27.6) and 50.0% (95% CI, 29.9 to 67.2) for arms A and B, respectively. The primary toxicities included esophagitis, pulmonary, and fatigue.

CONCLUSION

Arm A reached the primary end point with an estimated MST longer than 18 months and will be compared with a standard dose of TRT in a planned randomized phase III trial in the United States cooperative groups.

A phase I study of gemcitabine plus palliative radiation therapy for advanced lung cancer

PURPOSE

To determine the maximum-tolerated dose (MTD) and antitumor activity of twice-weekly gemcitabine when combined with palliative-dose thoracic radiation therapy (RT) in patients with recurrent or progressive lung cancer.

METHODS

Patients were enrolled in a dose-escalating study of gemcitabine with a starting dose level of 40 mg/m(2) given as 30-minute infusions twice weekly concurrent with RT. The RT dose was 30 Gy in 10 fractions, 5 fractions per week.

RESULTS

A total of 18 patients were enrolled on three dose levels: 40, 50, and 65 mg/m(2). Four patients came off study early due to rapid progression of disease and therefore were not evaluated. The MTD of gemcitabine was found to be 50 mg/m(2). Dose-limiting toxicities were grade-4 esophagitis in one patient and grade-4 neutropenia in another patient. Overall response included 1 partial response (PR). Local response included six PR, four minor response (MR), three stable disease (SD), and one progressive disease (PD).

CONCLUSION

The MTD of gemcitabine with concominant palliative thoracic radiation therapy is 50 mg/m(2) twice weekly. The DLTs observed were grade-4 esophagitis and grade-4 myelotoxicity at 65 mg/m(2).

Radiotherapy Does Not Influence the Severe Pulmonary Toxicity Observed With the Administration of Gemcitabine and Bleomycin in Patients With Advanced-Stage Hodgkin's Lymphoma Treated With the BAGCOPP Regimen: A Report by the German Hodgkin's Lymphoma Study Group

PURPOSE

To evaluate the effect of radiotherapy on the severe pulmonary toxicity observed in the pilot study of BAGCOPP (bleomycin, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone, and gemcitabine) for advanced-stage Hodgkin's lymphoma.

METHODS AND MATERIALS

Patients with Stage III or IV Hodgkin's lymphoma or Stage IIB with risk factors participated in this single-arm, multicenter pilot study.

RESULTS

Twenty-seven patients were enrolled on the study before its premature closure as a result of the development of serious pulmonary toxicity in 8 patients. The pulmonary toxicity occurred either during or immediately after the BAGCOPP chemotherapy course. Pulmonary toxicity contributed to one early fatality but resolved in the other 7 patients after cessation of gemcitabine and bleomycin, allowing continuation of therapy. Fifteen patients received consolidative radiotherapy, including 4 who previously had pulmonary toxicity. There were no reported cases of radiation pneumonitis and no exacerbation of pulmonary symptoms in the 4 patients who had had previous pulmonary toxicity.

CONCLUSIONS

The severe pulmonary toxicity observed in this study has been attributed to an interaction between gemcitabine and bleomycin. Gemcitabine (when administered without bleomycin) remains of interest in Hodgkin's lymphoma and is being incorporated into a new German Hodgkin's Lymphoma Study Group protocol that also includes consolidative radiotherapy. This study supports the concept of the integration of radiotherapy in gemcitabine-containing regimens in Hodgkin's lymphoma if there is an interval of at least 4 weeks between the two modalities and with a schedule whereby radiotherapy follows the chemotherapy.

Chimioradiothérapie exclusive des cancers bronchiques non à petites cellules localement évolués

Chemoradiation is one of the major therapeutic options in thoracic oncology: besides surgery, the best treatment for early-stage tumors, and chemotherapy, not only used in metastatic tumors, but also in a neoadjuvant and adjuvant setting, chemoradiation is the standard strategy for unresectable locally advanced non-small cell lung cancer. Its current modalities include three-dimensional conformal techniques, allowing dose escalation and sequential and concurrent combination with new generation cytotoxic agents to occur. Phase III trials are currently evaluating the benefit from induction and consolidation chemotherapy in this setting. New techniques of radiation may also increase the efficacy and the feasibility of radiation. This constant progress makes chemoradiation one of the most promising combined treatments in thoracic oncology.

Induction cisplatin-gemcitabine-paclitaxel plus concurrent radiotherapy and gemcitabine in the multimodality treatment of unresectable stage IIIB non-small cell lung cancer

BACKGROUND

To evaluate feasibility and safety of induction three-drugs combination chemotherapy and concurrent radio-chemotherapy in stage IIIB NSCLC.

PATIENTS AND METHODS

Patients with stage IIIB NSCLC were treated with three courses of induction chemotherapy, cisplatin 50 mg/m(2), paclitaxel 125 mg/m(2) and gemcitabine 1000 mg/m(2) on days 1,8 of every 21 day cycle. Patients without distant progressive disease were then treated with radiotherapy and concurrent weekly gemcitabine (250 mg/m(2)). Toxicity and response of radio-chemotherapy treatment have been assessed.

RESULTS

Between Jan 01 and Nov 02, 46 patients were enrolled. Grade 3+ hematological and non-hematological toxicity during the induction phase were 41.3% and 13.1%, respectively. In 38 patients a Clinical Response or Stable Disease was recorded and these patients underwent to concurrent radio-chemotherapy. Grade 3+ hematological and non-hematological toxicities were 8.2% in this group. Further response was observed in 66% of patients. Overall median survival time was 17.8 months, with a 3-year survival rates of 23%.

CONCLUSION

Three-drugs induction chemotherapy and concurrent radio-chemotherapy with weekly gemcitabine in locally advanced stage IIIB NSCLC is feasible and safe.

Fatal pneumonitis associated with intensity-modulated radiation therapy for mesothelioma

PURPOSE

To describe the initial experience at Dana-Farber Cancer Institute/Brigham and Women's Hospital with intensity-modulated radiation therapy (IMRT) as adjuvant therapy after extrapleural pneumonectomy (EPP) and adjuvant chemotherapy.

METHODS AND MATERIALS

The medical records of patients treated with IMRT after EPP and adjuvant chemotherapy were retrospectively reviewed. IMRT was given to a dose of 54 Gy to the clinical target volume in 1.8 Gy daily fractions. Treatment was delivered with a dynamic multileaf collimator using a sliding window technique. Eleven of 13 patients received heated intraoperative cisplatin chemotherapy (225 mg/m(2)). Two patients received neoadjuvant intravenous cisplatin/pemetrexed, and 10 patients received adjuvant cisplatin/pemetrexed chemotherapy after EPP but before radiation therapy. All patients received at least 2 cycles of intravenous chemotherapy. The contralateral lung was limited to a V20 (volume of lung receiving 20 Gy or more) of 20% and a mean lung dose (MLD) of 15 Gy. All patients underwent fluorodeoxyglucose positron emission tomography (FDG-PET) for staging, and any FDG-avid areas in the hemithorax were given a simultaneous boost of radiotherapy to 60 Gy. Statistical comparisons were done using two-sided t test.

RESULTS

Thirteen patients were treated with IMRT from December 2004 to September 2005. Six patients developed fatal pneumonitis after treatment. The median time from completion of IMRT to the onset of radiation pneumonitis was 30 days (range 5-57 days). Thirty percent of patients (4 of 13) developed acute Grade 3 nausea and vomiting. One patient developed acute Grade 3 thrombocytopenia. The median V20, MLD, and V5 (volume of lung receiving 5 Gy or more) for the patients who developed pneumonitis was 17.6% (range, 15.3-22.3%), 15.2 Gy (range, 13.3-17 Gy), and 98.6% (range, 81-100%), respectively, as compared with 10.9% (range, 5.5-24.7%) (p = 0.08), 12.9 Gy (range, 8.7-16.9 Gy) (p = 0.07), and 90% (range, 66-98.3%) (p = 0.20), respectively, for the patients who did not develop pneumonitis.

CONCLUSIONS

Intensity-modulated RT treatment for mesothelioma after EPP and adjuvant chemotherapy resulted in a high rate of fatal pneumonitis when standard dose parameters were used. We therefore recommend caution in the utilization of this technique. Our data suggest that with IMRT, metrics such as V5 and MLD should be considered in addition to V20 to determine tolerance levels in future patients.

Chemo-radiotherapy in non-small cell lung cancer: the role of gemcitabine

Gemcitabine (2'-2'-difluorodeoxycytidine) is a well-known cytotoxic drug and a potent radio-enhancer. We herein report the in vitro evidence of its activity, and the clinical experiences when this drug is administered concurrently with radiation. The phase I-II trials are analyzed, focusing on the recent ability to deliver irradiation with low incidence of side effects.

Radiation pneumonitis and pulmonary fibrosis in non-small-cell lung cancer: pulmonary function, prediction, and prevention

Although radiotherapy improves locoregional control and survival in patients with non-small-cell lung cancer, radiation pneumonitis is a common treatment-related toxicity. Many pulmonary function tests are not significantly altered by pulmonary toxicity of irradiation, but reductions in D(L(CO)), the diffusing capacity of carbon monoxide, are more commonly associated with pneumonitis. Several patient-specific factors (e.g. age, smoking history, tumor location, performance score, gender) and treatment-specific factors (e.g. chemotherapy regimen and dose) have been proposed as potential predictors of the risk of radiation pneumonitis, but these have not been consistently demonstrated across different studies. The risk of radiation pneumonitis also seems to increase as the cumulative dose of radiation to normal lung tissue increases, as measured by dose-volume histograms. However, controversy persists about which dosimetric parameter optimally predicts the risk of radiation pneumonitis, and whether the volume of lung or the dose of radiation is more important. Radiation oncologists ought to consider these dosimetric factors when designing radiation treatment plans for all patients who receive thoracic radiotherapy. Newer radiotherapy techniques and technologies may reduce the exposure of normal lung to irradiation. Several medications have also been evaluated for their ability to reduce radiation pneumonitis in animals and humans, including corticosteroids, amifostine, ACE inhibitors or angiotensin II type 1 receptor blockers, pentoxifylline, melatonin, carvedilol, and manganese superoxide dismutase-plasmid/liposome. Additional research is warranted to determine the efficacy of these medications and identify nonpharmacologic strategies to predict and prevent radiation pneumonitis.

Phase I/IIa Study of Cisplatin and Gemcitabine As Induction Chemotherapy Followed by Concurrent Chemoradiotherapy With Gemcitabine and Paclitaxel for Locally Advanced Non–Small-Cell Lung Cancer

Purpose

This is a phase I/IIa study to assess tolerance of gemcitabine and paclitaxel with radiotherapy in locally advanced non–small-cell lung cancer after induction chemotherapy.

Patients and Methods

Fifty-seven patients with stage III non–small-cell lung cancer were treated with cisplatin 80 mg/m2 on days 1 and 22 and gemcitabine 1,250 mg/m2 on days 1, 8, 22, and 28. Chemoradiotherapy began on day 43 as follows: cohort 1 (n = 9), gemcitabine 300 mg/m2 and paclitaxel 35 mg/m2 weekly (except week 9); cohort 2 (n = 9), gemcitabine 150 mg/m2 and paclitaxel 35 mg/m2 weekly (except week 9); cohort 3 (n = 10) and the 25 phase IIa patients, gemcitabine 300 mg/m2 and paclitaxel 135 mg/m2 every 21 days. Patients were treated with three-dimensional thoracic radiotherapy concurrently to 60 Gy.

Results

Weekly chemotherapy resulted in grade 4 esophageal and grade 3 or higher pulmonary toxicities. Reduction in dose density (cohort 3) led to a tolerable toxicity profile and was chosen as the phase IIa regimen. The response rate to induction was 49%, with stable disease in 40% of the patients. The response rate after consolidation therapy was 75% (94% for weekly chemotherapy v 82% for every 3 weeks). Median survival was 23 months, and 3-year survival was 45% for eligible patients. Local relapse occurred in 20% of the patients. Performance status of more than 1 predicted for poor outcome, but baseline pulmonary function did not. Dosimetric parameters including V15, V20, V30 (percent lung volume receiving ≥ 15, ≥ 20, and ≥ 30 Gy, respectively), and mean lung dose correlated with pulmonary toxicity.

Conclusion

Additional investigation with the 3-week schedule is warranted in patients with a good performance status based on the safety profile and preliminary efficacy data observed in this study.

A Phase I Study of Moderate-dose Radiation Therapy and Weekly Gemcitabine in Patients with Locally Advanced Non-small Cell Lung Cancer Not Suitable for Radical Chemoradiation Therapy

AIMS

To describe the toxicity and response seen in patients receiving moderate-dose radiation therapy with concurrent weekly low-dose gemcitabine in the management of locally advanced non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Eighteen patients with confirmed NSCLC were enrolled over a 17-month period from August 2000 until January 2002. All had localised disease but were considered unsuitable for curative therapy. Radiation therapy was given to a dose of 30 Gy in 15 fractions over 3 weeks. Gemcitabine was given weekly before and within 3 h of fractions 1, 6 and 11. The study was designed as a dose-escalation study, commencing at 100 mg/m2 and increasing at levels of 50 mg/m2, until the maximum tolerated dose (MTD) was reached.

RESULTS

The MTD was regarded as being 150 mg/m2. The major acute toxicity observed was oesophagitis. Skin reactions were also reported. The overall response rate in all patients was 88%, with 44% achieving a complete response.

CONCLUSION

The combination of gemcitabine and moderate-dose radiation therapy is feasible, and offers low toxicity and excellent response rates in patients with localised NSCLC not suitable for high-dose therapy.

Concurrent chemoradiotherapy with low dose weekly gemcitabine in stage III non-small cell lung cancer

Background

Combined chemoradiotherapy (CRT) is the treatment of choice for stage III NSCLC. Gemcitabine (G) is a novel deoxycitidine analogue that has been proven to be a potent radiosensitizer. Twenty-two consecutive patients were treated with concurrent CRT to demonstrate the tolerability and efficacy of low dose G given weekly as radiosensitizer in stage III NSCLC.

Methods

Patients with KPS ≥70, adequate bone marrow reserve, with no prior radiotherapy (RT) and surgery were included. Eighteen patients had received prior induction chemotherapy (CT). G (75 mg/m²/week) was infused over 1 hour for 6 weeks. Thoracic RT was given two hours later over 6 weeks at 1.8 Gy/day fractions (total dose of 61.2 Gy). Pulmonary toxicity was evaluated with computed tomography scans in 6 weeks.

Results

Median age was 60 years (range, 48–75), median follow-up was 15 months (range, 2–40). Sixty-eight percent of patients were male and median KPS score was 90. Conformal 3D-RT planning was used in 64% of patients. G was given for a median of 5 weeks (range 1–9). Twelve patients (54.6%) received all planned CT. G was stopped because of intolerance in 6 and death in 2 patients. Seven patients (31.8%) had radiation pneumonitis. Twenty patients were evaluated for overall response, 1 patient (4.5%) had clinical CR, 81.8% had PR while 9.5% had SD. Median overall survival (OS) was 14 ± 5 months (95% CI 3–25). One- and 2-year OS rates were 55% and 38%. Sixteen patients died of disease-related events (6 with progression of primary tumor, 8 due to metastatic disease), 2 patients died of other causes. One- and 2-year progression-free survival and local control rates were 56%, 27% and 79%, 51%, respectively.

Conclusion

G might be used as radiosensitizer for patients with stage III NSCLC who could not receive full doses CT with concurrent RT.

Phase I study of concomitant chemoradiotherapy with paclitaxel, fluorouracil, gemcitabine, and twice-daily radiation in patients with poor-prognosis cancer of the head and neck

PURPOSE

We previously demonstrated high locoregional control, in patients with poor-prognosis head and neck cancer (HNC), using paclitaxel, 5-fluorouracil, hydroxyurea, and concomitant hyperfractionated radiotherapy. In the present phase I trial, gemcitabine, a novel antimetabolite with strong radiation-enhancing activity, replaces hydroxyurea. We sought to determine the recommended phase II dose and clinical efficacy in poor-prognosis HNC patients.

EXPERIMENTAL DESIGN

Seventy-two patients enrolled. Eligibility criteria included recurrent or second primary HNC, metastases or expected 2-year survival <20%. Chemoradiotherapy consisted of 5-fluorouracil, 600 mg/m(2)/d, for 5 days; paclitaxel, 100 mg/m(2) on Day 1; and concurrent 1.5 Gy twice-daily radiation for 5 days. Gemcitabine was dose escalated, 50-300 mg/m(2) on day 1. Cycles repeated every 14 days until the completion of chemoradiation. Dose-limiting toxicities (DLTs) included: neutropenic fever; grade > or =4 neutropenia or thrombocytopenia for >4 days; grade > or =4 mucositis or dermatitis for >7 days; or grade 3 toxicity necessitating chemotherapy dose reductions. Non-DLT dose reductions in 5-fluorouracil and/or paclitaxel were allowed.

RESULTS

Seventy-nine percent of assessable patients experienced a clinical response. Five-year actuarial survival is 33.0%, and locoregional control is 61.4%. The recommended phase II dose of gemcitabine in this regimen is 100 mg/m(2) during cycles 1-5 (1 of 7 patients with DLT) or 200 mg/m(2) delivered only during cycles 3-5 (3 of 19 with DLT). Grades 3 and 4 mucositis (56 and 21%, respectively) and dermatitis (25 and 21%, respectively) were common.

CONCLUSIONS

Gemcitabine, 5-fluorouracil, paclitaxel, and twice-daily radiation, delivered on alternating weeks, is active in patients with poor-prognosis HNC, although severe mucositis limits the clinical applicability of this regimen. Refinements in radiotherapy, including intensity-modulated radiation therapy, may improve the tolerance for this regimen.

Increased expression of pro-inflammatory cytokines as a cause of lung toxicity after combined treatment with gemcitabine and thoracic irradiation

BACKGROUND AND PURPOSE

Preclinical evidence suggesting gemcitabine potentiates the anti-tumor effects of irradiation has resulted in clinical trials to evaluate the treatment efficacy of gemcitabine and concurrent thoracic irradiation in non-small-cell lung cancer (NSCLC). Although these studies demonstrated favorable tumor response, this combined treatment modality was accompanied by severe treatment-related toxicities predominantly of the lung. In an attempt to elucidate the determinants of lung toxicity for gemcitabine, we analyzed the expression of the pro-inflammatory cytokines TNF-alpha, IL-1alpha and IL-6 in the lung tissue of mice treated with gemcitabine and concurrent thoracic irradiation.

MATERIALS AND METHODS

Four study groups were defined: C57BL/6J mice that received neither irradiation nor gemcitabine (NT-group), those that received gemcitabine (120 mg/kg intraperitoneal, i.p.) but no irradiation (GEM-group), those that underwent thoracic irradiation (12 Gy) without gemcitabine (XRT-group), and those that received both gemcitabine (120 mg/kg i.p., 2 h before irradiation) and thoracic irradiation (GEM/XRT-group). The mice were sacrificed at 1 h, 1 and 3 days, 1, 2 and 4 weeks post-treatment (p.t.). The mRNA expression of TNF-alpha, IL-1alpha and IL-6 in the lung tissue was quantified by competitive RT-PCR. The cellular origin of the cytokine expression was identified by immunohistochemistry. The cytokine expression was correlated with histopathological alterations.

RESULTS

The TNF-alpha, IL-1alpha and IL-6 expression in the lung tissue of the GEM/XRT mice was clearly higher at all assessment time points compared to the NT mice (statistically significant at 1 h, 1 and 3 days, 1, 2 and 4 weeks p.t.), XRT mice (statistically significant at 1 week p.t.) or GEM mice (statistically significant at 1 h, 1 and 2 weeks p.t.). Maximal treatment-induced cytokine expression in the lung tissue of the GEM/XRT mice occurred already at 1 week p.t. (TNF-alpha: 30.9 +/- 5.3/IL-1alpha: 28.3 +/- 5.0/IL-6: 4.9 +/- 0.1 times basal level), and coincides with pathohistologically discernable interstitial pneumonitis. The elevated levels of TNF-alpha and IL-1alpha have been found to correlate with immunohistochemical staining of the bronchiolar epithelium and predominantly of inflammatory cells.

CONCLUSIONS

Our data provide evidence that the increased expression of pro-inflammatory cytokines and the induction of a cytokine-triggered inflammatory response may be a determinant of the observed elevated lung toxicity after concurrent treatment with gemcitabine and thoracic irradiation.

Concurrent low-dose cisplatin and thoracic radiotherapy in patients with inoperable stage III non-small cell lung cancer: a phase II trial with special reference to the hemoglobin level as prognostic parameter

PURPOSE

To evaluate the efficacy of concurrent radiochemotherapy in patients with stage III non-small cell lung cancer (NSCLC), and to examine the effect of hemoglobin levels on survival of those patients. The negative impact of anemia on survival has been noticed for other cancer sites including the head and neck, and the uterine cervix, but it has been rarely described in NSCLC cancer patients treated with radiotherapy.

METHODS

From April 1995 through March 2002, 56 patients with inoperable stage III non-small lung cancer were treated with radiotherapy consisting of 60 Gy (50 Gy+10 Gy boost) given in 30 fractions of 2 Gy daily, 5 days a week, over a period of 6 weeks, and concurrent low-dose daily chemotherapy (CHT) consisting of 6 mg/m(2) of cisplatin given Mondays-Fridays during weeks 1-2 and 5-6. All patients had stage III disease and ages ranged from 39 to 81 years old (median 63.9 years).

RESULTS

The 2-year and 3-year survival rates were 34% and 16%, respectively. Patients with a pretreatment hemoglobin level superior or equal to 11.6 g/dl had a 2-year survival rate of 52% as compared to 15.5% for patients with a pretreatment hemoglobin level inferior to 11.6 g/dl (p=0.0075). Patients with higher KI (>70%) showed better survival rates than those with lower KI. Surprisingly, patients in stage IIIA did not survive significantly longer than those in stage IIIB. Hematological toxicity (grade > or =2) prevailed (25%), followed by esophageal (5.4%) and bronchopulmonary (2%) toxicity. Only three patients experienced acute grade 3 hematological toxicity. Because of acute toxic effects, irradiation was interrupted in 8 patients (14.3%) for 7-13 days (median 7.5 days). Late high-grade (> or =3) toxicity was not found. No grade 4 toxicity or treatment-related deaths were observed during this study.

CONCLUSION

Our data show that concurrent radiotherapy with daily low dose cisplatin is well tolerated, and shows survival rates comparable to more aggressive treatment regimens. A combination of this chemotherapy with accelerated hyperfractionated radiotherapy might improve the results in the future. Furthermore, we could show that the hemoglobin levels prior to therapy have an influence on the prognosis, where lower levels were associated with worse outcome. Further trials should consider supplementation with erythropoietin.

Gemcitabine-induced severe pulmonary toxicity

Gemcitabine is a relatively new deoxycytidine analog (2',2'-difluorodeoxycytidine) with structural similarities to cytosine arabinoside (Ara-C). Activity of gemcitabine is demonstrated in the treatment of many solid tumors, like pancreas, ovarian and nonsmall cell lung cancer (NSCLC). Although gemcitabine is considered as a drug with a good safety profile, cases of gemcitabine-induced severe pulmonary toxicity (GISPT) were reported as for Ara-C. We performed a systematic review of reported cases on the GISPT. Twenty-nine clinical trials especially interesting NSCLC patients (21) and 21 reported cases recording 40 patients were analyzed. The incidence of the GISPT varies from 0 to 5%. The clinical presentation is a subacute clinical syndrome and is frequently nonspecific. The predominant radiographic pattern on chest X-ray are reticulo-nodular interstitial infiltrates. It was postulated that the physio-pathological mechanism of the GISPT was an inflammatory reaction of the alveolar capillary wall cytokine-mediated, which created an abnormal permeability of its membrane. After the differential diagnosis were ruled out, the discontinuation of the drug and the early initiation of steroids and diuretics are the most frequently performed treatments. Under these conditions, the outcome was favorable in a delay of few days generally for a majority of patients but 20% of patients died. Some risk factors, as a previous pulmonary disease or a previous thoracic irradiation, for the occurrence of the GISPT were proposed. GISPT is rare but sometimes fatal. Its a necessity to increase awareness about it to enhanced an early and suitable management of patients developing such a toxicity after gemcitabine administration.

A prospective study on lung toxicity in patients treated with gemcitabine and carboplatin: clinical, radiological and functional assessment

BACKGROUND

Small series and retrospective studies have suggested that treatment with gemcitabine may be associated with pulmonary toxicity. However, a prospective evaluation of cancer patients treated with gemcitabine-based chemotherapy without neoplastic involvement of the thorax and without administration of radiotherapy has not been performed.

PATIENTS AND METHODS

To investigate this issue, 41 consecutive patients receiving gemcitabine and carboplatin underwent prospective evaluation of lung function, which included pulmonary symptoms, pulmonary function tests, arterial blood gases and radiographic studies. Assessment was performed before and after completion of chemotherapy in all patients. Patients with a substantial decline in diffusion capacity for carbon monoxide (DLCO), defined as a drop of > or = 20%, were reassessed 2 months later.

RESULTS

After chemotherapy, there were no significant changes in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, alveolar volume or total lung capacity. In contrast, there was a significant decline in DLCO (73 +/- 22 versus 67 +/- 24% predicted; P = 0.017) and in carbon monoxide transfer coefficient (KCO) (89 +/- 24 versus 80 +/- 24% predicted; P = 0.004). Arterial blood gases did not change following treatment. Ten of the 41 patients (24%) exhibited a substantial decline in DLCO, which, however, recovered within 2 months (DLCO at baseline, immediately after therapy and at 2 months after completion of treatment, 84 +/- 14, 58 +/- 16 and 77 +/- 17% predicted, respectively; P < 0.001; baseline DLCO versus DLCO at 2 months, P > 0.05). Four of the 41 patients (10%) experienced dyspnea, which was self-limiting, with the exception of one patient who developed interstitial lung fibrosis. Among the various risk factors examined, older age, female gender and lower baseline DLCO were associated with more profound changes in DLCO post-treatment.

CONCLUSIONS

This prospective analysis showed that the combination of gemcitabine and carboplatin induces a significant, but reversible, decrease in diffusion capacity, which is mostly asymptomatic. Thus, this regimen is safe as regards clinically significant lung toxicity.

Promising combination therapies with gemcitabine

Because treatment regimens for breast cancer commonly include gemcitabine, we evaluated two promising combinations in preclinical studies: gemcitabine (Gemzar; Eli Lilly and Company, Indianapolis, IN) with either ionizing radiation or docetaxel (Taxotere; Aventis Pharmaceuticals, Inc, Parsippany, NJ). In breast cancer cell lines that expressed either wild-type p53 (MCF-7) or mutant p53 (MCF-7/Adr), sensitivity to the cytotoxic effects of gemcitabine during a 24-hour incubation was similar (IC(50) values 80 and 60 nmol/L in MCF-7 and MCF-7/Adr, respectively). Both cell lines were well radiosensitized by gemcitabine at the corresponding IC(50), with radiation enhancement ratios of 1.6 to 1.7. Although the MCF-7 cells accumulated nearly twice as much gemcitabine triphosphate compared with the MCF-7/Adr cells, a similar reduction in 2'-deoxyadenosine 5'-triphosphate pools was observed. While the number of dying cells, as measured by sub-G1 DNA content or S-phase cells unable to replicate DNA, differed between the wild-type p53 or mutant p53-expressing cell lines, neither parameter correlated with radiosensitization. Docetaxel was a more potent cytotoxic agent than gemcitabine in MCF-7 cells (IC(50) = 1 nmol/L). Strong synergistic cytotoxicity was observed in cells treated with gemcitabine (24 hours) followed by docetaxel (24 hours) or the reverse sequence. However, simultaneous addition of the two drugs was antagonistic. To determine whether synergy with radiation or docetaxel was mediated by increased DNA damage, DNA double-strand breaks (double-strand breaks) were measured by immunostaining for phosphorylated H2AX. Ionizing radiation produced more double-strand breaks than gemcitabine alone, while no significant double-strand breaks formed with docetaxel alone. The addition of docetaxel or ionizing radiation to gemcitabine-treated cells did not increase H2AX foci formation. These results show that the combination of gemcitabine with ionizing radiation or docetaxel produces strong, schedule-dependent synergy in breast cancer cells that is not mediated through increasing DNA double-strand breaks.

Radiation and third-generation chemotherapy

All of the third-generation chemotherapeutic agents reviewed in this article are independently active against NSCLC, although the agents differ significantly in their cellular and molecular mechanisms of cytotoxicity. All have also been shown to potentiate radiation effects, and thus are promising in exerting further cytotoxicity when used in combination chemoradiation therapy for locally advanced NSCLC. Although the toxicity to normal tissue varies among these agents when used alone, phase I/II clinical results consistently demonstrated higher risk and severity of esophagitis and pneumonitis when these agents were administered concurrently with thoracic radiation. These results were consistent with the radiosensitization properties of all these agents. Nonetheless, most chemoradiation combinations have been made feasible through careful phase I studies that establish safe doses of these agents given concurrently with radiation. Indeed, phase I outcomes consistently have demonstrated the need for dose reduction compared with doses applied in the stage IV, metastatic disease setting (see Tables 1 and 2). There have been many different dose schedules in phase I/II studies for stage III NSCLC, and most have yielded improved response rates with these agents. For all these agents discussed, multiagent chemoradiation increased toxicity when compared with single agent chemoradiation, particularly in the risk of neutropenia, and the tumor response rates were no better than single-agent chemoradiation. Most studies have not reached an adequate interval for survival endpoint to assess the impact on survival using multiagent chemoradiation. A few earlier studies using paclitaxel chemoradiation, in fact, showed that the significant improvement in tumor response rate resulted in only a small gain in survival outcome. Despite much preclinical research conducted with these agents, the optimal sequence and dose of drug and the optimal schedule for combining the two modalities remain unknown. Optimal sequencing of the chemoradiation regimens may improve distant disease control and primary tumor control, as was seen in studies that administered both full-dose induction chemotherapy and concurrent chemoradiation at reduced drug dose and in studies that administered consolidative, full-dose chemotherapy after chemoradiation. Strategically altering the treatment schedule may also enhance the radiosensitizing effects while keeping toxicity low, such as was seen in the pulsed low-dose paclitaxel chemoradiation reported by Chen et al . This pulsed low-dose schedule resulted in superior tumor response (100%) and durable primary tumor control while keeping the toxicity low. Other methods to minimize normal tissue injury and to deliver higher radiation doses, such as conformal three-dimensional radiotherapy that excludes nontarget tissues from the radiation field, are under investigation. Marks and colleagues were able to deliver radiation to 80 Gy using accelerated hyperfractionation radiation after induction chemotherapy. Intensity-modulated radiotherapy is expected to revolutionize the targeting of tumor and exclusion of normal tissues from the high-dose radiation volume in the future. Integrating biologic response modifiers, radioprotectors, and molecular targeting strategies also are being investigated. It remains unclear which agent among the third-generation drugs performs better for combination chemoradiation. The CALGB 9431 study reported by Vokes et al provided some preliminary information, in that it was a randomized phase II study of a three-arm comparison of cisplatin-containing, two-drug combination chemoradiation with one of the third-generation agents. Although direct statistical comparison between the treatment arms was not valid for a phase II setting, such an analysis did indeed reveal similar overall response rates for these three arms. Chemoradiation using third-generation chemotherapeutic agents has improved local tumor response rates, with enhanced radiation toxicity such as esophagitis and pneumonitis. The challenge of targeting distant disease control for locally advanced NSCLC continues.

Radiosensitization of vinorelbine and gemcitabine in NCI-H460 non–small-cell lung cancer cells

PURPOSE

Results from recent clinical studies of gemcitabine and vinorelbine have encouraged the use of this combination concurrently with radiotherapy in the treatment of non-small-cell lung cancer, although preclinical data are limited. The present study aimed to quantify the in vitro interaction and radiosensitizing effect of gemcitabine and vinorelbine individually and in combination.

METHODS AND MATERIALS

Cytotoxicity was measured by exposing NCI-H460 cells to gemcitabine and/or vinorelbine simultaneously or sequentially, followed by irradiation at 0-10 Gy. Clonogenic cell survival assays were performed. Flow cytometry was used to measure the effects of both drug and radiation on cell cycle distribution. Apoptosis was assessed by morphologic criteria, by sub-G1 changes using flow cytometry assay, and by Annexin-V binding assay.

RESULTS

Both drugs showed single-agent activity against NCI-H460 cells and targeted different phases of the cell cycle. When both drugs were used in combination, they showed schedule-dependent interaction. An antagonistic effect was observed with simultaneous exposure to the two drugs. The optimum combination schedule was sequential exposure to vinorelbine followed by gemcitabine 24 h later. Both drugs showed radiosensitization effects. The radiosensitization effect of gemcitabine was evident when radiation was given immediately after 4-h incubation. However, the radiosensitization effect of vinorelbine was time dependent and observed with radiation given at 24 h postincubation. Apoptosis induced by gemcitabine increased gradually, reaching 20% at 72 h posttreatment. In contrast, apoptotic cell death was an early feature in vinorelbine-treated cells, reaching approximately 40% at 24 h.

CONCLUSIONS

The individual cytotoxic effects of gemcitabine and vinorelbine on NCI-H460 cells are phase specific, and the combined effect of gemcitabine and vinorelbine is sequence dependent. The radiosensitizing effects of both drugs seem to be related to enhanced apoptosis.

Phase I/II study of daily carboplatin, 5-fluorouracil and concurrent radiation therapy for locally advanced non-small-cell lung cancer

A study was undertaken to determine the maximum tolerated dose, the dose-limiting toxicities and the response rate of carboplatin and 5-fluorouracil administered daily with concurrent thoracic radiation therapy in patients with locally advanced non-small-cell lung cancer. In a phase I/II clinical trial, patients with histologically documented, unresectable stage IIIA or IIIB non-small-cell lung cancer (NSCLC) were enrolled. Carboplatin (20-40 mg m(-2) 2-h infusion, daily) and 5-fluorouracil (200 mg m(-2) 24-h continuous infusion, daily) were administered concurrently with radiotherapy on days 1-33. Radiotherapy, with a total dose of 60 Gy, was delivered in 30 fractions on days 1-40. In the phase I portion, the daily dose of carboplatin was escalated from 20 to 40 mg m(-2). Once the maximum tolerated dose (MTD) and recommended dose (RD) of carboplatin was determined, the study entered the phase II portion. In the phase I portion, the daily MTD and RD of carboplatin were 40 and 35 mg m(-2), respectively. The dose-limiting toxicity was neutropenia. In the following phase II study, 30 patients were entered and the objective response rate was 76.7% (95% CI, 62-92%) and the local control rate was 85.7%. The median survival time was 19.8 months, with a survival rate of 70% at 1 year, 36.7% at 2 years. The major toxicities of treatment were neutropenia (>or=grade 3, 87.9%) and thrombocytopenia (>or=grade 3, 23.3%). This combined therapy for locally advanced non-small-cell lung cancer is promising and shows acceptable toxicity.

Gemcitabine as a Radiosensitizer for Nonresectable Feline Oral Squamous Cell Carcinoma

Eight cats with locally advanced, oral squamous cell carcinoma (SCC) were treated with a combination of gemcitabine and palliative radiotherapy. Low-dose gemcitabine was administered twice weekly (25 mg/m2) in conjunction with megavoltage radiation in 6 Gray (Gy) fractions for a total dose of 36 Gy. Responses included two complete and four partial responses, and two cats had no response to therapy. Median duration of remission was 42.5 days (range, 11 to 85 days). Median survival time was 111.5 days (range, 11 to 234 days). This data suggests that a combination of low-dose gemcitabine and palliative radiation therapy may be tolerable for cats with oral SCC and may cause a therapeutic benefit.

Hyperfractionated radiotherapy and paclitaxel for locally advanced/unresectable pancreatic cancer

PURPOSE

To determine prospectively the maximal tolerated dose and potential antitumor activity of weekly paclitaxel with concurrent hyperfractionated radiotherapy in patients with locally advanced and/or unresectable pancreatic cancer.

METHODS AND MATERIALS

We embarked on Phase I-II study of hyperfractionated radiotherapy using a concomitant in-field boost to a total dose of 63.80 Gy in 6 weeks at 1.1 Gy/fraction. Paclitaxel was administered weekly on Days 1, 8, 15, 22, 29, and 36 as a 3-h infusion. Paclitaxel doses were escalated from 20 mg/m(2)/wk to 70 mg/m(2)/wk. Twenty patients were studied, 14 women and 6 men (mean age 64 years). Some patients presented with one or more symptoms. Obstructive jaundice was the main presenting symptom in 10 patients and epigastric pain in 14. All patients had unresectable histologically proven adenocarcinoma of the pancreas (15 head, 4 body, and 1 tail). Reasons for unresectability were involvement of the portal vein, and/or superior mesenteric artery (n = 14), paraaortic nodes (n = 8), and medically inoperable (n = 1). Fourteen patients underwent a biliary bypass procedure before treatment (four endoscopic stenting, five choledochojejunostomy, and five cholecystojejunostomy). The follow-up period ranged from 14 to 66 months (median 44).

RESULTS

The dose-limiting toxicity was observed at 70 mg/m(2)/wk. Grade IV Radiation Therapy Oncology Group late GI toxicity was seen in 1 patient in the form of duodenal stricture and hemorrhage. Grade II gastrointestinal adverse effects occurred in 13 patients and Grade 3 in 1 patient. No neurologic morbidity was encountered. Eight patients required cytokine support for Grade 2 and 3 neutropenia. The treatment course was delivered within the planned time in 80% of the patients. Complete relief of pain occurred in 10 of 14 patients. The CA 19-9 level was either stable or decreasing in 12 of 15 patients. Of 17 assessable patients, stable disease was seen in 10, regression in 2, a partial response in 3, and a complete response in 2.

CONCLUSION

The use of hyperfractionated radiotherapy to a dose of 63.80 Gy with concomitant weekly paclitaxel is tolerated. The maximal tolerated dose of paclitaxel for this study was 60 mg/m(2)/wk. The preliminary objective responses denote activity of the regimen. We recommend testing this regimen in larger scale studies.

The Emerging Role of Gemcitabine in Combination with Radiation in Locally Advanced, Unresectable Non–Small-Cell Lung Cancer

The median survival for patients with locally advanced non-small-cell lung cancer (NSCLC) remains 18 months, at best, in cooperative group efforts. Integrating new agents into the standard combined modality treatment paradigm is a daunting challenge. Gemcitabine has activity in advanced NSCLC and is a potent radiosensitizer, but preclinical trials did not delineate an optimal dose or schedule, and early attempts to graft full-dose gemcitabine (1000 mg/m2/week) onto standard radical thoracic radiation therapy (RT) were marked by significant grade 4 and 5 toxicity. More recent trials, however, have shown that attenuated doses of 150-300 mg/m2/week during radiation (XRT) are safer and potentially efficacious. Higher doses produce dose-limiting esophageal and pulmonary toxicities. Using a twice-weekly schedule, the maximum tolerated dose is 35 mg/m2. The use of 3 dimensional conformal RT may enable significant dose escalations while substantially reducing esophageal exposure and minimizing toxicity. The cooperative oncology groups are just beginning to evaluate gemcitabine in this setting. Cancer and Leukemia Group B, in a randomized phase II study, assessed combination gemcitabine and cisplatin in both the induction and radiosensitizing setting. During the induction phase, gemcitabine was given 1250 mg/m2 on days 1 and 8 every 3 weeks for 2 cycles in combination with cisplatin 80 mg/m2 every 3 weeks, and then reduced to 600 mg/m2 days 1 and 8 every 3 weeks during XRT. The overall response rate was 63% with median survival of 18.3 months and 1-year and 3-year survival rates of 68% and 28%, respectively. Radiation Therapy Oncology Group is currently spearheading a phase I study of concurrent radiation and weekly gemcitabine in combination with either weekly carboplatin or paclitaxel. Ongoing efforts will also evaluate the role of gemcitabine either alone or in combination with docetaxel in the consolidation setting after definitive chemoradiation has been completed. Whether gemcitabine in combination with radiation, with or without other agents, will ultimately prove superior to standard chemoradiation regimens remains to be determined.

Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

PURPOSE

To determine cross-resistance to anti-tumor treatments in 2',2'difluorodeoxycytidine (dFdC, gemcitabine)-resistant human tumor cells.

METHODS AND MATERIALS

Human lung carcinoma cells SW-1573 (SWp) were made resistant to dFdC (SWg). Sensitivity to cisplatin (cDDP), paclitaxel, 5-fluorouracil (5-FU), methotrexate (MTX), cytarabine (ara-C), and dFdC was measured by a proliferation assay. Radiosensitivity and radioenhancement by dFdC of this cell panel and the human ovarian carcinoma cell line A2780 and its dFdC-resistant variant AG6000 were determined by clonogenic assay. Bivariate flowcytometry was performed to study cell cycle changes.

RESULTS

In the SWg, a complete deoxycytidine kinase (dCK) deficiency was found on mRNA and protein level. This was accompanied by a 10-fold decrease in dCK activity which resulted in the >1000-fold resistance to dFdC. Sensitivity to other anti-tumor drugs was not altered, except for ara-C (>100-fold resistance). Radiosensitivity was not altered in the dFdC-resistant cell lines SWg and AG6000. High concentrations (50-100 microM dFdC) induced radioenhancement in the dFdC-resistant cell lines similar to the radioenhancement obtained at lower concentrations (10 nM dFdC) in the parental lines. An early S-phase arrest was found in all cell lines after dFdC treatment where radioenhancement was achieved.

CONCLUSIONS

In the dFdC-resistant lung tumor cell line SWg, the deficiency in dCK is related to the resistance to dFdC and ara-C. No cross-resistance was observed to other anti-tumor drugs used for the treatment in lung cancer. Sensitivity to ionizing radiation was not altered in two different dFdC-resistant cell lines. Resistance to dFdC does not eliminate the ability of dFdC to sensitize cells to radiation.

Gemcitabine in non-small cell lung cancer

Gemcitabine is considered to be one of the most active drugs in the treatment of non-small cell lung cancer (NSCLC). When used as a single agent, gemcitabine yielded response rates consistently > 20%, with a uniformly good tolerance profile. Preclinical data indicated synergism between gemcitabine and platinum compounds, such as cisplatin or carboplatin. The gemcitabine-cisplatin combination is considered one of the reference regimens for advanced NSCLC and the recommended schedule is gemcitabine 1000 - 1250 mg/m(2) on days 1 - 8 and cisplatin 70 - 80 mg/m(2) on days 1 or 2. In order to avoid many of the non-haematological toxicities associated with cisplatin, several trials evaluated the gemcitabine-carboplatin combination. Previous trials using the 28-day schedule showed unacceptable haematological toxicity. Recent studies demonstrated the activity and feasibility of gemcitabine-carboplatin combination using a 21-day schedule, with carboplatin administered on day 1 and gemcitabine on days 1 and 8. Gemcitabine can be combined with one of the other new agents, such as the taxanes or vinorelbine, to create novel non-platinum-doublets. Although encouraging, the available data are still conflicting and non-platinum-based combinations are not indicated outside clinical trials. Three-drug combinations increased toxicity and failed to demonstrate any advantage over standard doublets in advanced NSCLC. Gemcitabine is active and well tolerated in elderly patients and represents a reasonable therapeutic option. Although no Phase III trials have been conducted to compare gemcitabine to the best supportive care or docetaxel in pretreated NSCLC, gemcitabine alone or in combination with vinorelbine or one of the taxanes can be considered a valid option for second-line treatment in patients who had a previous response or who achieved stable disease with a platinum-containing regimen. Gemcitabine is considered the most radiopotentiating agent available amongst the newer agents we have in terms of activity and toxicity, but the routine use of gemcitabine in combination with radical thoracic radiotherapy, although promising, is not yet recommended. Further testing of gemcitabine-based combinations with concurrent radiation is underway.

Combined-Modality Therapy for Inoperable non—small-Cell Lung Cancer Using Gemcitabine

Combined-modality therapy with chemotherapy and radiation appears to be the most efficacious therapeutic modality for patients with locally advanced non-small-cell lung cancer. Most of the trials exploring this approach have utilized older agents such as cisplatin, vinblastine, and etoposide. Recent data suggest that gemcitabine may be superior to these agents therapeutically, with the ability to produce similar or improved outcomes and a milder overall toxicity profile. Moreover, gemcitabine is able to sensitize tumor cells to radiation-induced apoptosis as well as lead to induction of cells in the radioresistant S phase of the cell cycle. These results have suggested that gemcitabine should be tested in concurrent chemoradiotherapy regimens. Significant toxicities seen in the initial trials have led to a number of trials modifying the regimen so that efficacy might be maintained without adverse effects. These modifications have included lowered gemcitabine doses and reduced radiation field sizes. The results of these newer studies suggest that this approach can be highly efficacious, with 1-year survival rates > 50% and response rates as high as 88%.