A randomized trial comparing preoperative chemotherapy plus surgery with surgery alone in patients with non-small-cell lung cancer

Chemotherapy in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer can no longer be regarded as resistant to chemotherapy, and there have recently been considerable improvements in the use of the older agents and advances in the identification of new drugs. Recent meta-analysis has also confirmed the view that chemotherapy can have small but modest survival benefits. Although in the treatment of stage IV disease the criteria of efficacy have concentrated on tumour response rates, more recently it has become obvious that these patients can also benefit in terms of improved symptom control.

RECENT ADVANCES

For patients with locally advanced stage III disease there have been important developments indicating the benefit of combined modality treatment with chemotherapy and thoracic irradiation. Furthermore, the use of neoadjuvant chemotherapy indicates that resection is possible in about half the patients, and on pathological examination of 15%-20% of the resected specimens there is no evidence of residual tumour. These results justify an increase in the use of systemic chemotherapy in this disease.

K-ras genotypes and prognosis in non-small-cell lung cancer

BACKGROUND

Despite major advances in the treatment of many kinds of cancer over the past 25 years, the overall 5-year survival of non-small-cell lung cancer patients has scarcely improved. Even in stage I which has the best outcome long-term survival still falls below 70%. Since intriguing data suggest that the identification of genetic markers might allow prognosis to be assessed case by case. We were prompted to evaluate K-ras gene mutations as a putative prognostic marker in this neoplasm.

MATERIALS AND METHODS

We used the polymerase chain reaction (PCR) followed by allele specific oligonucleotide (ASO) hybridization or single-strand conformation polymorphism (SSCP) assays, to detect K-ras mutations in DNA from formalin-fixed, paraffin-embedded tumor samples. K-ras mutations were examined in 192 stage I to IV non-small-cell lung cancer patients.

RESULTS

K-ras mutations were detected in 51 of 192 of the cases studied (27%). All K-ras mutations detected by PCR/ASO hybridization were also identified by SSCP. In stage I disease, the median survival was 46 months in those patients whose tumors had no K-ras mutations and 21 months in those with aspartic acid and serine mutations at K-ras codon 12; in patients with stage IIIA disease, median survival time was 16 months in the K-ras negative group and 7 months in the aspartic acid and serine mutation group. No significant differences were observed for the remaining amino acid substitutions of K-ras, nor were they observed at all in more advanced disease.

CONCLUSIONS

K-ras gene status has strong prognostic value in patients with stage IIIA non-small-cell lung cancer. The survival curve for patients with stage I and K-ras codon 12 aspartic or serine mutations is close to that of patients with stage IIIA without K-ras mutations. However, a non-small-cell lung cancer K-ras genotypic classification should be validated in larger studies.

Adjuvant and neo-adjuvant chemotherapy in non-small cell carcinoma

BACKGROUND

There have been many trials investigating the influence of chemotherapy on survival following surgery or radiotherapy in non-small cell lung cancer. Few have been large enough to detect the sort of differences likely to emerge, given the limited efficacy of chemotherapy. The technique of meta-analysis using individual patient data can allow worthwhile conclusions to be derived from the contradictory data generated by multiple small trials. This paper summarizes published data from randomized trials testing: (1) adjuvant chemotherapy following 'curative' surgery; (2) neoadjuvant chemotherapy prior to surgery in cases of borderline operability; (3) chemotherapy in inoperable, but still localized, disease where standard therapy would be radical radiotherapy.

CONCLUSION

All the indications are that combinations including cisplatin confer a small, but real, prolongation of survival. However, meta-analysis is not a substitute for individual trials large enough to detect clinically important differences in survival. Other worthwhile endpoints like symptom control, quality of life and cost cannot be addressed in a meta-analysis. Large, well designed and executed randomized trials are still urgently needed if more time and money is not going to be wasted in the search for better treatments in lung cancer.

Is there a role for chemotherapy of non-small cell lung cancer?

This paper reviews the results of individual studies and meta-analyses of chemotherapy of non-small cell lung cancer. The published results from studies of chemotherapy as part of a combined modality therapy which have been carried out in the last decade are conflicting. Some show a statistically superior survival for the group receiving chemotherapy compared with a best supportive care group, while the others show no advantage. The differences, however, are small. Meta-analysis of data from published randomized trials has been used by some authors to assess combination chemotherapy compared to supportive or palliative treatment of patients of non-resectable non-small cell lung cancer. In some of the randomized trials and meta-analyses results, a statistically significant effect on survival parameters following chemotherapy against non-small cell lung cancer is shown. The clinical significance of these observations is questionable and the results from larger ongoing trials must be awaited before chemotherapy is used routinely in the treatment of advanced NSCLC.

The role of induction therapy and surgery for stage IIIA lung cancer

In stage IIIA lung cancer, the role of induction chemotherapy or chemoradiotherapy prior to surgical resection has been studied extensively in patients identified preoperatively as having N2 disease. Both types of induction treatment have resulted in significant response and resection rates. Three trials have randomized patients to this form of treatment versus primary surgery. In all three trials the combined modality therapy has been significantly more effective, resulting in longer median survival times and estimated five year survival times. This new-found optimism for combined modality therapy including surgery is presently being compared to more standard therapy - chemoradiation for patients suffering from this stage of disease. In the future, this type of treatment will be investigated in earlier stage disease, classically treated by surgery, but often yielding less than satisfactory five year cancer free survival times.

Current status of surgical resection for lung cancer

There have been no major breakthroughs in surgical management for primary lung cancer during the past 40 years. Improved 5-year survival relates primarily to improved preoperative staging and appropriate selection of patients for resection. Perioperative morbidity and mortality, however, has been significantly reduced. Certain principles pertain to current surgical management: resection remains the best treatment for patients with localized, non-small cell primary lung cancer. Accurate preoperative diagnosis and staging: whenever possible, it is desirable to establish the diagnosis and cell type before operation. Accurate evaluation of the N status warrants wide application of invasive staging with mediastinoscopy or a variant. Indications for resection: only patients in whom a complete resection is anticipated should be selected for surgery. Such cases included T1 to T4 stages, N0 and N1 tumors, and selected N2 cases. The indication for resection in patients with hematogenous metastases are anecdotal. Intraoperative staging: accurate and deliberate intraoperative staging with evaluation of nodes using the American Thoracic Society map is highly desirable. The nature of nodal metastases exerts a critical influence on prognosis and in the selection of patients for surgical resection. At present, there is no clear indication for adjuvant therapy in surgically resected cases other than for evaluation and clinical trials.

Future directions in clinical research for lung cancer

Even since the Surgeon General's 1964 report, the mortality rate from lung cancer has continued to rise. Although there is evidence that this continued increase in mortality will slow or level in the next decade, lung cancer mortality is a major health problem destined to remain with us for at least the next generation. There have been no established advances in the early detection or prevention of lung cancer in the last 30 years and our therapies have increased the cure rate only from 5 to 13% in this 30-year interval. Biologic advances have outpaced clinical advances in recent times and many of the advances are now ripe for clinical exploitation. There are currently more exciting clinical trials for all phases of lung cancer than at any time and it will be stimulating to witness the results of the clinical trials discussed herein. Hopefully, the results of these studies will lead to a decrease in lung cancer mortality in the next century, much as it increased in the past century.

A phase 3 randomized trial of immediate combination chemotherapy vs delayed combination chemotherapy in patients with completely resected stage II and III non-small cell carcinoma of the lung

The purpose of this trial (Lung Cancer Study Group [LCSG] 853) was to perform a comparative study of immediate combination chemotherapy (cyclophosphamide, doxorubicin, cisplatin [CAP]) vs delayed combination chemotherapy (CAP) administered at the time of first systemic relapse in patients with completely resected stage II and stage III non-small cell cancer of the lung. We randomly assigned 188 patients with resected stage II or stage III non-small cell lung cancer of the lung (squamous, 53%; nonsquamous, 47%) to receive either immediate or delayed combination chemotherapy. Careful intraoperative staging was performed in all patients. Before randomization, patients were stratified according to stage--II (hilar nodes positive) vs III (mediastinal nodes positive or T3)--and histologic features (squamous vs nonsquamous). Ninety-four patients were randomized to receive immediate CAP vs 94 patients randomized to receive delayed CAP. Prognostic variables such as extent of disease, histologic features, sex, race, TN status, and Karnofsky performance status were equally distributed between randomized groups. The treatment groups differed with respect to greater than 10% weight loss. Forty-one percent of patients had stage II disease and 59% of patients had stage III disease. Median time to recurrence (19.5 months) and survival (32.7 months) did not differ between treatment groups. Immediate combination chemotherapy was associated with a 12% reduction in risk of recurrence and an 18% reduction in risk of death, although these rates were not statistically significant. Histologic features, sex, race, Karnofsky performance status, nodal status, and weight change were associated with higher risks of recurrence.

Current status of neoadjuvant therapy for non-small cell lung cancer

Any program of therapy for clinically advanced non-small cell lung cancer (NSCLC) that would increase the incidence of local tumor control and decrease the likelihood of distant metastatic disease would be of obvious benefit. The objective of neoadjuvant therapy is to eradicate the primary tumor and micrometastatic disease. In the past 10 years, many trials have been completed to evaluate neoadjuvant therapy and they have included sequential chemoradiotherapy, concurrent chemoradiotherapy, chemotherapy/surgery, and chemoradiation/surgery. These trials have predominately been phase 2 trials and have demonstrated that chemotherapy is generally well tolerated, surgery is technically feasible, and operative morbidity and mortality are not excessive. Long-term survival for patients with clinically advanced NSCLC is improved when compared with historic controls. These trials have demonstrated a greater than 50% clinical response rate and in approximately 20% of patients who have undergone resections, the tumor is sterilized. This latter group of patients demonstrate significantly improved survival. Cost-benefit ratios and quality of life have yet to be evaluated. Final determination of the effectiveness of neoadjuvant therapy for NSCLC awaits completion of phase 3 trials.

Long-term results of neoadjuvant ifosfamide, cisplatin, and etoposide combination in locally advanced non-small-cell lung cancer

Thirty-three patients with T3,N2,M0 or T4,N2,M0, non-small-cell lung cancer (NSCLC) took part in a phase 2 study in an attempt to evaluate the feasability of neoadjuvant chemotherapy followed by surgery and thoracic radiotherapy. Chemotherapy consisted of daily administration of the following treatment: etoposide, 100 mg/m2; cisplatin, 25 mg/m2; ifosfamide, 1.5 g/m2; and mesna, 1.8 g/m2 for 4 days. Three cycles were planned starting every 21 days. Responding patients underwent a thoracotomy in order to attempt a resection and then received a 45 Gy of thoracic radiotherapy. The results of response and resection rates have been published and the present final report deals with the long-term results. Chemotherapy induced a 55 percent partial response rate and a 15 percent complete response rate allowing a complete resection in 55 percent of the patients. Complete remission was histologically confirmed for the five complete responders. Although the median survival was short (10 months), six patients were long-term survivors (3-year survival rate: 19 percent). Survival was significantly influenced by the type of resection: patients for whom a complete resection was possible survived the longest with a median survival three times that of the other patients. Modalities of relapses differed according to the results of surgery: 8 of the 15 patients who did not undergo a complete surgical resection experienced a local relapse during the first 18 months of follow-up whereas in the complete resection group, central nervous system metastasis was the main site of relapse. We conclude that the neoadjuvants ifosfamide, cisplatin, and etoposide in patients with locally advanced NSCLC are feasible to use and allow a 19 percent 3-year survival rate. These results are the rationale of an ongoing randomized study comparing neoadjuvant chemotherapy followed by surgery and surgery alone. This study is designed to test whether neoadjuvant chemotherapy improves survival of patients with locally advanced NSCLC.

Management of non-small cell lung cancer with direct mediastinal involvement

The results of surgical treatment were analyzed for 102 patients with non-small cell lung cancer invading the mediastinum by direct extension (T3 and T4), but those who had N2 disease were excluded to eliminate the adverse prognostic effect of this nodal subset. The histologic type was squamous cell carcinoma in 55 patients, adenocarcinoma in 40, and large cell carcinoma in 7. There were 58 T3 tumors invading the mediastinal pleura or fat, phrenic nerve, vagus nerve, pericardium, or pulmonary vessels and 44 T4 lesions invading the aorta, vena cava, esophagus, trachea, spine, or atrium. Resection included lobectomy (33 patients), pneumonectomy (32 patients), and limited resection (6 patients). Complete resection was possible in 46 patients and incomplete or no resection was possible in 56. The interstitial implantation of radioactive sources to control residual tumor also was undertaken in 43 patients. The operative mortality was 6%. The overall survival (Kaplan-Meier) was 19% at 5 years (median survival time, 18 months). Factors found to be significantly affect survival were complete resectability and the histologic type. With complete resection, the 5-year survival was 30% (p = 0.005). The 5-year survival in patients with adenocarcinoma or large-cell carcinoma was 30%, compared with 14% in patients with squamous cell carcinoma (p = 0.002). The extent of mediastinal involvement (T3 versus T4) influenced resectability and survival, and this approached statistical significance (p = 0.055). We conclude that most patients with non-small cell carcinoma and mediastinal invasion do poorly with primary surgical treatment.

Neoadjuvant therapy: a novel and effective treatment for stage IIIb non-small cell lung cancer. Southwest Oncology Group

Neoadjuvant therapy has become an accepted treatment for stage IIIa, but not for stage IIIb, non-small cell lung cancer, which is usually considered incurable and treated nonsurgically. We determined the feasibility of neoadjuvant therapy in the setting of stage IIIb non-small cell lung cancer in a prospective multi-institutional trial. For patients to be eligible for entry into the study, they had to have pathologically documented T1-4 N2-3 disease. Treatment consisted of: (1) cisplatin (50 mg/m2) given on days 1, 8, 29, and 36 plus VP-16 (50 mg/m2) given on days 1 to 5 and 29 to 33, together with concurrent radiotherapy (4,500 cGy; 180 cGy per daily fraction); and (2) surgical resection performed 3 to 5 weeks after induction of medical therapy, if the response was stable, partial, or complete. Of the 126 total eligible patients entered into the study, 51 patients had stage IIIb tumors (24 with T4 tumors and 27 with N3 disease). This consisted of 34 men and 17 women with a median age of 57 years. Thirty-two (63%) patients (18 with T4 tumors and 14 with N3 disease) underwent resection of the primary tumor, with a 5.2% operative mortality. There was no difference in the operative time, blood loss, and length of hospital stay for the T4 versus the N3 patients. For all 51 patients, survival at 2 years was 39%. Sites of relapse in all patients were mainly distant, even though patients with N3 disease did not initially have involved N3 nodes resected.(ABSTRACT TRUNCATED AT 250 WORDS)