Small cell lung cancer 1973-1983: early progress and recent obstacles

Chemotherapy with or without radiation therapy in limited small-cell carcinoma of the lung

We conducted a prospective, randomized study to clarify the role of radiotherapy of the primary tumor in limited small-cell cancer of the lung. After stratification for sex and for performance score based on the ability to ambulate, patients were randomly assigned to receive initial radiotherapy plus chemotherapy, delayed radiotherapy plus chemotherapy, or chemotherapy alone. The chemotherapy consisted of cyclophosphamide, etoposide (VP-16-213), and vincristine, with doxorubicin subsequently replacing etoposide in alternate cycles 7 through 18. Chemotherapy was given every three weeks for 18 months. The radiotherapy comprised 4000 rad in four weeks, followed by a 1000-rad "boost" directed against residual disease. All patients received prophylactic whole-brain radiation. The patients enrolled totaled 426, and 399 were evaluable. There was a statistically significant difference in the frequency of complete responses in favor of the two radiotherapy regimens (P = 0.0013). Failure-free survival was also longer with these two regimens (P less than 0.001), as was the interval before treatment failure in the chest (P less than 0.001) and overall survival (P = 0.0099). As expected, toxic effects--chiefly neutropenia--were also increased. The addition of radiotherapy of the primary tumor to combination chemotherapy improved both complete-response rates and survival, with increased but acceptable toxicity.

Cyclic alternating polychemotherapy with or without upper and lower half-body irradiation in small cell anaplastic lung cancer. A randomized study

Ninety-six patients with small cell anaplastic lung carcinoma were given monthly chemotherapy with vincristine-doxorubicin-cyclophosphamide alternating with CCNU-methotrexate-etoposide for 18 months or until evidence of progressive disease. Forty-four patients were randomized to chemotherapy alone and 52 patients to chemotherapy plus 600 cGy of both upper and lower half-body irradiation given day 60 and 100, respectively. In 78 evaluable patients surviving more than 100 days the overall response rate was identical in the two arms of the study, 68% vs. 66%. However, time to progression was significantly shorter in the irradiated patients (P = 0.05). Only 25% of the irradiated patients tolerated greater than or equal to 75% of the scheduled dose of chemotherapy, against 91% of the non-irradiated patients (P = 0.0001). Thus, half-body irradiation was associated with a shorter time to progression and a decreased ability to give maintenance chemotherapy at proposed doses.

Small cell carcinoma of the lung. A progress report of 15 years' experience

To assess the results of therapeutic advances in the treatment of small cell carcinoma of the lung (SCCL) achieved during the past 15-year period at a single large institution, 508 patients treated between 1968 and 1982 were divided into two groups: 157 patients (66 in the category of limited-stage disease and 91 in the extensive-stage disease category) treated with low-dose small-volume radiotherapy (RT) (time dose fractionation [TDF] 49-66) and with cyclophosphamide alone or a COPP program during the first period of 7 years (1968-1974); 351 patients (180 in limited and 171 in extensive stage) treated with multidrug chemotherapy (CT) and high-dose large-volume RT (TDF 73-89) during the second period of 8 years (1975-1982). For patients with limited-stage cancer, 5-year actuarial survivals were 3% versus 7% for the periods 1968-1974 versus 1975-1982, respectively, P less than 0.01. For patients with extensive-stage cancer, the median survival time (MST) and 2-year actuarial survivals were 5 months and 2% versus 7 months and 4% for the periods 1968-1974 versus 1975-1982, respectively. To evaluate the outcome of a contemporary approach, i.e., CT alone, with RT reserved for locoregional failure, 180 patients with limited-stage cancer who were treated (1975-1982) were further analyzed for MST, 2- and 5-year actuarial survival figures, and local-tumor control rates according to the therapeutic approaches employed: CT + RT (112); CT alone (36); RT alone (17); and surgery (S) +/- CT +/- RT (15). Although the 36 patients in CT alone seems a small number, 17 of the 36 patients were enrolled in this approach in 1981-1982, reflecting a shift of emphasis from RT to CT. The MST and 2-year actuarial survival figures were 11 months and 0% versus 13 months and 21% for CT alone versus CT + RT respectively, P less than 0.05. CT + RT achieved a 5-year cure rate of 8%. S +/- CT +/- RT or RT alone also achieved 5-year cure rates of 8% and 10.5%, respectively, in selected subsets of patients. Local relapse rates were 80% (29/36) versus 25% (28/112) for CT alone versus CT + RT. These data emphasize the importance of thoracic RT given at the early phase of treatment to improve long-term survival for patients with limited-stage SCCL.

Acute nonlymphocytic leukemia after treatment of small cell lung cancer

From 1977 to 1982, 377 patients with small cell lung cancer were treated at Vanderbilt University Medical Center. All patients received combination chemotherapy consisting of cyclophosphamide, doxorubicin, and vincristine (CAV) with or without methotrexate, etoposide, and/or hexamethylmelamine. Thoracic and/or prophylactic cranial irradiation was administered to 159 (42 percent) and 192 (51 percent) patients, respectively. Acute nonlymphocytic leukemia was observed in two patients at 22 and 81 months from the start of therapy. The relative risk of leukemia was 154 (95 percent confidence limit, 38 to 293). A Kaplan-Meier estimate of the cumulative probability of leukemia was 1.9 +/- 1.4 percent seven years after the start of treatment. The relative risk of leukemia is significantly increased in this group of patients (p less than 0.0001). Acute nonlymphocytic leukemia is a long-term complication of small cell lung cancer therapy.

Atypical endocrine tumors of the lung: a histologic, ultrastructural, and clinical study of 19 cases

Lung cancers are divided by light microscopic criteria into several categories, but only two categories are recognized clinically--small cell and non-small cell carcinomas. Transmission electron microscopy has revealed unexpected complexity within each category, blurring the distinctions between them. The present study was undertaken to determine the incidence of dense-core, neuroendocrine-type granules in lung tumors diagnosed by light microscopy as non-small cell carcinomas, i.e., atypical endocrine tumors, and the clinical significance of their identification. Of 205 consecutive primary and metastatic lung cancers, 19 (9 per cent) diagnosed as non-small cell carcinomas by light microscopy were seen to contain neuroendocrine-type granules by electron microscopy and thus were reclassified as atypical endocrine tumors of the lung. Staining with silver stains, periodic acid-Schiff (PAS), PAS with diastase digestion, and mucicarmine was positive in 18, 15, 14, and eight of the 19 cases, respectively. Electron microscopy revealed glandular differentiation in 12 cases and tonofilaments in eight cases, although none of the tumors met the criteria for identification as squamous cell carcinomas. Clinically, the cancers appeared to resemble non-small cell carcinoma more closely than small cell carcinoma. Median survival (12 months) and response to combination chemotherapy (22 per cent) were in the range reported for non-small cell carcinoma. There were no complete responses, despite the use in some cases of regimens active against small cell carcinoma. However, one patient, the only one to date so treated, had a dramatic response to streptozotocin/5-fluorouracil, suggesting that, as in metastatic carcinoid, this combination may have value in the treatment of atypical endocrine tumors of the lung.

A 10-year experience with combined modality therapy for stage III small cell lung carcinoma

During the past 10 years, 240 patients with Stage III small cell lung carcinoma (SCLC) were treated with one of five chemotherapy programs plus thoracic irradiation. In addition, prophylactic cranial irradiation was administered concurrently with thoracic irradiation to 194 patients receiving CAML-HC, VCAM, or MOCA. Seventy-two patients had disease confined to the chest (Stage IIIM0), 30 patients had disease in the chest plus ipsilateral supraclavicular nodal involvement (Stage IIIM0SCN+), and 138 patients had distant metastatic disease (Stage IIIM1); the median survivals were 15.2 months, 12.6 months, and 8.4 months, respectively. The overall complete response rate was 30% and the overall response rate (complete and partial) was 76%. The overall response rates by stage were 86% for Stage IIIM0, 90% for Stage IIIM0SCN+, and 67% for Stage IIIM1. Eight patients (3%) were alive and free of disease at 24 months. Due to continued disease relapse in this group (four of eight patients), long-term survivors should not be identified for a minimum of 3.5 years from the time of initial therapy. Prophylactic cranial irradiation (PCI) effectively reduced the incidence of central nervous system (CNS) relapse in patients with a complete response to therapy (44% relapse without PCI versus 13% relapse with PCI, P less than 0.01). More effective chemotherapy is required for the successful treatment and improved long-term survival of patients with SCLC.

CNS relapse despite prophylactic cranial irradiation (PCI) in small cell lung cancer (SCLC)

CNS relapse after PCI may reflect either suboptimal radiation dose schedules or reseeding from other sites of active disease. A retrospective study has been undertaken to investigate these alternative mechanisms of treatment failure. Between August 1981 and December 1983, 30 patients with SCLC treated by induction chemotherapy, followed by high-dose cyclophosphamide (7 Gm/m2), were selected for PCI on the basis of clinical, radiological, and bronchoscopic CR. Pretreatment CT brain scans were normal in all patients, and 20 Gy mid-plane dose in 5 daily fractions were delivered by lateral fields to whole brain using megavoltage X rays and localizing check films. Progressive focal neurological signs of cranial metastases developed in 7/30 (23%) patients 3-11 months after PCI, confirmed on CT scanning in 4 patients. Relapse at other sites, predominantly the thorax, occurred in all seven patients at intervals of 1-6 months prior to CNS relapse. Published clinical data of tumor volume doubling times in SCLC predict longer CNS relapse-free intervals after PCI than those observed in our patients if reseeding was responsible for relapse. This suggests that incomplete eradication of intracranial disease is the main cause of CNS relapse after PCI. Higher equivalent radiation doses may improve the results of PCI.

Small cell lung cancer: a problem of tumor heterogeneity

Small cell undifferentiated carcinoma represents a subtype of lung cancer that possesses biologic and clinical characteristics that make it significantly distinct from other forms. A major impact on the natural history of this disease has been accomplished during the past 15 years, including the potential for cure by non-surgical treatment modalities. Further progress in the management of this disorder has been impaired by a number of factors that appear to be inherent to the biology of the tumor and its clinical features. Analysis of initial clinical trials and more detailed examination of this tumor in vitro have permitted the elucidation of many barriers to curative outcome presently being evaluated at the laboratory and clinical levels. These include clear biologic and morphologic heterogeneity; problems with chemotherapy responsiveness including drug resistance; the potential for combining chemotherapy and radiation modalities; the re-examination of the role of surgical intervention in selected patients; and the need to deal with central nervous system dissemination of tumor cells. Further advances in this disease will be dependent on the successful integration of laboratory and clinical disciplines.

Long-term survival in limited-stage small cell lung carcinoma. Experience in Rochester, New York from 1975 to 1981

All patients with limited-stage small cell lung carcinoma (SCLC) diagnosed between January 1975 and 1981 in Rochester, New York, were collected. One hundred one patients were evaluable. By reviewing an entire community's experience with long follow-up, we were able to describe the response rates and survival in a large unselected population and compare them to results from concurrent cooperative group studies. Median survival for the entire group was 51 weeks, with only 18% alive at 130 weeks. There was no evidence for improvement in response or survival during the 6 years of study. Treatment results in the community as a whole were no different from that seen with cooperative group studies. A group who had initial surgery followed by adjuvant therapy had a significantly better survival and more long-term survivors than those not receiving surgery, but rare long-term survivors were seen with all treatment categories. Except for this small surgical subgroup, no other characteristics could be identified which were predictably associated with long-term disease-free survival. The overall poor survival of patient with localized SCLC suggests a need for the development of novel initial approaches to therapy.

Chemotherapy versus chemotherapy plus irradiation in limited small cell lung cancer. Results of a controlled trial with 5 years follow-up

One hundred and forty-five patients with limited stage small cell lung cancer were included in a randomized trial to evaluate the effect of chemotherapy with or without chest irradiation. Seventy-six patients were allotted chemotherapy alone while 69 patients received the same chemotherapy plus radiotherapy, 40 Gy in split-course, administered in weeks 6 and 10 after the initiation of chemotherapy. The chemotherapy consisted of lomustine, cyclophosphamide, vincristine and methotrexate. Patients treated with chemotherapy alone survived for a median of 52 weeks compared to 44 weeks in patients receiving the combined regimen (P = 0.055). After exclusion of five early deaths and one patient refusing the irradiation plus 14 completely resected patients, the remaining 65 patients receiving chemotherapy alone and the 60 patients treated with chemotherapy plus radiotherapy were included in a new analysis. The difference in survival duration which could be ascribed to treatment with or without chest irradiation thereby diminished (P = 0.24). Eighteen months' disease-free survival was obtained in 9.2% of the 65 patients and in 9.8% of the 60 patients. The complete remission rates were 37% and 46%, respectively, (P = 0.33) and the median durations of complete remission were 40 weeks and 52 weeks (P = 0.67). Treatment failure of the primary tumour occurred in 85% of patients treated with chemotherapy alone in contrast to 61% of patients receiving the combined regimen (P = 0.005). Seventy-nine of these patients underwent autopsy at which no residual chest disease was observed in 17% and 37%, respectively (P = 0.045). The combined regimen was more toxic than chemotherapy alone resulting in significantly greater dose reductions and more pronounced thrombocytopenia. Lung and pericardial fibrosis was responsible for four deaths among the complete responders in the radiotherapy group. The combined regimen thus tended to be more efficacious with respect to tumour control at the expense, however, of increased toxicity which per se, eliminated a potential improvement of the overall therapeutical results.

Non-small-cell lung cancer. Major cause of late mortality in patients with small cell lung cancer

Among 360 patients with small cell lung cancer treated in National Cancer Institute therapeutic trials from 1973 to 1982, 40 were two-year cancer-free survivors. Of these 40 patients, six had later development of non-small-cell lung cancer at 3.5 to 8.0 years (median 5.1) after the diagnosis of small cell lung cancer. Three had the second malignant tumor in the contralateral lung, one in a different lobe, and two in the same lobe as the initial small cell lung cancer. Ten patients had relapses of small cell lung cancer at 2.1 to 6.2 years (median 3.2) from diagnosis. Three recurrences were in the same site or lobe as the initial lesion, four in the same lobe and in sites outside the thorax, and three solely in sites outside the thorax. It is concluded that these non-small-cell lung cancers usually represent second primary lung tumors and that most late small cell lung cancers represent relapses occurring up to 6.2 years from diagnosis. In this study, the risk of development of non-small-cell lung cancer after two years of disease-free survival following small cell lung cancer is 4.4 percent per person-year, approximately 10 times higher than the rate of 0.5 percent previously determined in screening studies of men at high risk for lung cancer. Non-small-cell lung cancer represents more than a third of lung cancer deaths in patients with small cell lung cancer surviving beyond two years from diagnosis and more than half of lung cancer deaths beyond three years. It is recommended that all patients treated for small cell lung cancer discontinue smoking.

Neoadjuvant Chemotherapy with Vincristine, Bleomycin and Methotrexate Combined with Radiotherapy in Advanced Head and neck Squamous Cell Carcinoma

From September 1980 to August 1981, 25 patients with advanced head and neck squamous cell carcinoma were treated at the Centro Oncologico, Trento, by a chemo-radiotherapeutic combination. The treatment protocol consisted of 4–6 courses of VBM (vincristine, bleomycin and methotrexate) followed by conventional radiotherapy (65 Gy). Only to VBM responders (15 patients) were administered 10 cycles of vincristine-methotrexate. At the end of induction chemotherapy an overall response of 60 % (12 % complete, 48 % partial) was obtained. At the end of radiotherapy the responses were 52.5 % complete and 35.5 % partial, for an overall response of 88 %. The overall survival at 60 months was 8 %. This combined approach, in spite of the satisfactory immediate local response rate, does not offer advantages for survival in comparison to conventional treatment modalities.

Small cell lung cancer: results of a phase II study of 1,2,4 triglycidylurazol

Fourteen patients with small cell lung cancer (SCLC) received treatment with 1,2,4 triglycidylurazol (TGU) 600 mg/m2 or 800 mg/m2 as an IV bolus every 4 weeks. Twelve patients had received previous chemotherapy consisting of a five-drug regimen given for the short duration of only 9 weeks. All had measurable disease. Following TGU 11 patients had progressive disease and 3 patients had stable disease. The most frequent toxicity was nausea and vomiting, which occurred in all patients but was generally mild. Myelosuppression was common with a median white blood count nadir of 2.5 X 10(9)/l (range 0.9-7.4 X 10(9)/l) and median platelet count nadir of 76 X 10(9)/l (range 5-173 X 10(9)/l. Alopecia, thrombophlebitis, and hepatic or renal toxicity were not observed. In this study, TGU had no activity in SCLC, and the dose-limiting toxicity was myelosuppression.

Prognostic influence of TNM staging and LDH levels in small cell carcinoma of the lung (SCCL)

To better define the prognostic factors influencing the response to therapy and survival in small cell carcinoma of the lung (SCCL), an expanded "TNM" type staging system was developed and investigated in a series of 73 protocol treated patients. Because serum LDH levels at disease presentation have been correlated to disease extent, response to therapy, and treatment outcome in a number of malignancies, including SCCL, these interrelationships were also analyzed in the protocol patients. The TNM system was found to be a more descriptive and specific "shorthand" for denoting sites of involvement and for indicating the body burden of tumor than the traditional limited-extensive disease (LD-ED) system. A clear statistical advantage could not be shown over the LD-ED system for predicting chemotherapy response or survival, although there were trends suggesting the TNM system could divide patients into three prognostic subgroups. Serum LDH proved to be a useful index of disease extent and therapy outcome. LDH levels at presentation were proportionately higher with more extensive tumor, measured by either the LD-ED or TNM staging. High LDH predicted poorer responses to chemotherapy and lower survival within similar stage subgroups compared to patients with normal LDH levels. The negative effect of elevated LDH was independent of hepatic involvement and did not predict subsequent hepatic failure in any consistent way. The SCCL TNM staging system proposed needs further refinement and should be tested with larger patient numbers. LDH, along with other tumor markers recently identified, need to be integrated into the staging system to form an overall prognostic index.

Influence of surgical resection prior to chemotherapy on the long-term results in small cell lung cancer. A study of 150 operable patients

The effect of surgical resection, prior to chemotherapy, on the long-term results obtained in treatment of operable patients with small cell lung cancer (SCC) was evaluated in a consecutive series of 874 patients treated with intensive combination chemotherapy with or without irradiation between 1973 and 1981. Evaluation of disease stage and operability was based on broncho-mediastinoscopy, chest X-ray, bone marrow examination, peritoneoscopy with liver biopsy and lung function tests. The same staging procedures were applied for restaging performed after 18 months of chemotherapy. The series comprised 440 patients with extensive disease and 437 with limited disease of whom 150 were regarded operable. Fifty-four operable patients received no thoracotomy because the treatment policy of SCC did not include surgery at the hospitals from which they were referred. These patients served as a reference with which data on operated patients were compared. Resections were performed in 52 patients while 44 were regarded to be irresectable at the thoracotomy. Thirty-six resections were regarded histologically complete while 16 patients proved to have microscopic (9 pts) or macroscopic (7 pts) residual tumor. The number and per cent of 30 months disease-free survivors in the various categories of the 874 patients were as follows: Completely resected, 12/36 patients (33%); Resected with residual tumor, 2/16 (12.5%); Operable but non-operated, 7/54 (13%); Irresectable, 3/44 (6.8%); Non-operable patients with limited disease, 15/284 (5.3%) and with extensive disease, 11/440 (2.5%). The similarity between rates of long-term survival observed in resected patients with residual tumor and operable, non-operated patients suggests that resection, per se, has no significant influence on long-term results in SCC. The relatively high rate of long-term survival in completely resected patients may therefore primarily be a result of early stage disease at the initiation of chemotherapy.

Recent advances in the biology of small cell lung cancer

Advances in the techniques for culturing human tumors in vitro, especially lung cancer cells, have greatly facilitated studies of the biologic properties of both small cell and non-small cell lung cancer cells. Detailed analysis has been done of well-characterized cell lines of both groups with respect to growth properties, biomarker and antigen expression, cytogenetics, and oncogene amplification and expression. Two major conclusions have emerged from these studies: (1) considerable heterogeneity exists within a given tumor type (eg, SCLC) in the expression of a given biomarker, and (2) overlap in the expression of biomarkers exists between cells of SCLC and non-SCLC, suggesting a common stem cell for all types lung cancer. In the future, clinical trials the impact of the biologic properties of cells on responses to therapy and survival will need assessment.

Radiotherapy for small cell lung cancer

The role of radiation therapy in the primary management of small cell lung cancer is very much a matter of current debate. Its value in palliative treatment is unquestioned. Disappointment in the apparent inability to demonstrate improvement in survival in some randomized studies as a result of locoregional radiotherapy and prophylactic cranial irradiation may be due to the use of inappropriate study analysis. Recent studies using the end points of 2-year survival and local thoracic control do demonstrate improvements associated with locoregional thoracic radiotherapy. Factors such as total dose and radiation fraction size may be important. Large-field irradiation is also currently attracting interest, but its use should remain a research investigation.

Small cell bronchogenic carcinoma

We have attempted to highlight the most important aspects of SCBC in this review. The significant strides made in a variety of areas have been associated with increased response rates and survival as well as with a prolonged disease-free interval in a fraction of patients. The consensus is that 50% or more of patients with LD can achieve a CR, with an overall objective response rate of 80% or greater and a median overall survival of 14 months or longer. Furthermore, 15% to 20% of such patients may expect a disease-free interval of at least three years that appears to be associated with cure in at least some of these patients. Patients with ED may experience a 20% or greater CR, an 80% or greater objective response, and have a median overall survival of at least seven months. Extensive research is ongoing in a variety of areas. Further refinements in developing more effective chemotherapeutic regimens are likely, as is obtaining new information concerning the intensity, duration, and selection of chemotherapeutic agents and their role in relationship to radiotherapy. Improvement in radiotherapy techniques may lead to improved therapeutic results. Only recently has a reevaluation of the role of surgery in SCBC begun to take place. Also, several new areas of investigation are on the horizon, ranging from improved staging with thoracic and abdominal computed tomography to the role of warfarin, monoclonal tumor antibodies, and several currently investigational chemotherapeutic and biologic response modifier agents.

The effect of combined modality therapy on local control and survival

The systemic component of combined modality therapeutic programs has influenced both the selection of the approach to local control and survival in a number of tumor types. The more effective systemic therapy is against metastatic cancer by itself, the greater the impact on local control and survival. This observation is consistent with the invariable inverse relationship between curability and tumor cell number. For some common cancers, local control is good, but survival remains poor because of the inability to deal effectively with micrometastases. Improved systemic treatment is likely to have an impact on survival may shift local control measures, in some cases, to radiation therapy or lesser surgery without radiation therapy. There remains a substantial number of tumor types where both local control and survival is poor. In these tumors, improvement in local control by itself is not likely to improve survival because of the presence of micrometastases, but such improvements must occur before we can have a true evaluation of the systemic treatment of micrometastases in these tumors. The recent understanding that the metastatic process is under genetic control and the cloning of metastases genes offers a substantial opportunity to control this process and influence both local control and survival.

Phase II trial of nimustine (ACNU; 3-[4-amino-2-methyl-5-pyrimidinyl) methyl]-1-(2-chloroethyl)-1-nitrosourea hydrochloride) in patients with small cell carcinoma of the lung after failure on combination chemotherapy

Thirty-nine previously treated patients received Nimustine in a phase II trial to test the therapeutic activity in refractory small cell lung cancer. Nimustine was given as a direct i.v. injection of 100 mg/m2 with treatments repeated every six weeks. Three partial remissions of 56, 123 and 355 days duration were noted among 34 evaluable patients. Thrombocytopenia was prominent with a median platelet nadir of 47,000/microliter. We conclude that Nimustine has minor antitumor-activity in heavily pretreated patients with small cell lung cancer. The definitive value of Nimustine in the treatment of small cell lung cancer, as well as its superiority over its parent compounds remains to be established.

Small cell carcinoma of the lung

Small cell lung cancer is a common, usually fatal neoplasm. Although palliative therapy is available for the majority of patients, only a very small minority enjoy long-term survival. Ironically, this neoplasm is nearly entirely preventable and a successful antismoking program is desperately needed. Our efforts to understand the basic biology of this tumor should continue, and, hopefully, will eventually translate into improvements in therapy. In addition to following the leads provided by basic research, a concerted clinical research effort needs to continue to build upon the advances already achieved.

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

Sixty-three evaluable patients with limited small cell lung carcinoma were entered into two pilot studies alternating 6 cycles of combination chemotherapy (Doxorubicin 40 mg/m2 d 1; VP16213 75 mg/m2 d 1, 2, 3; Cyclophosphamide 300 mg/m2 d 3, 4, 5, 6; and Methotrexate 400 mg/m2 d 2--plus folinic acid rescue--or Cis-Platinum 100 mg/m2 d 2) with 3 courses of mediastinal radiotherapy as induction treatment. The first course of radiotherapy started 10 days after the second cycle of chemotherapy; there was a 7 day rest between chemotherapy and radiotherapy courses. This 6 month induction treatment was followed by a maintenance chemotherapy. The total mediastinal radiation dose was increased from 4500 rad in the first study to 5500 rad in the second. Both protocols obtained a complete response (CR) rate of greater than 85% (with fiberoptic bronchoscopy and histological verification). Local control at 2 years was 61% in the first study and 82% in the second. Relapse-free survival at 2 years was 32 and 37%, respectively. Toxicity was acceptable. We conclude that our results justify further clinical research in alternating radiotherapy and chemotherapy schedules.

Computed tomography in the staging of small cell lung cancer: implications for combined modality therapy

Computed tomography of the thorax and abdomen, from the thoracic inlet to the renal hila, was performed as part of initial staging in 51 patients with small cell carcinoma of the lung (SCCL). The computed tomographic (CT) scans were repeated after completion of chemotherapy, as part of routine restaging and assessment of response to therapy. To identify the ways in which CT scanning uniquely benefited evaluation of initial disease extent in comparison to other diagnostic studies exclusive of CT scan, all diagnostic and clinical data were reviewed. CT scan identified more advanced intrathoracic disease than chest radiography in 82% of patients. Mediastinal node involvement not appreciated by chest radiography was seen in 61% of patients. Adrenal and retroperitoneal node involvement, not suspected by other studies, was identified by CT scan in 31% and 12% of patients, respectively. Thirty percent of the patients staged as limited disease (LD) were advanced to extensive disease (ED) by CT scan findings. While confirmation, by biopsy, of positive CT findings was not consistently accomplished, restaging CT scans provided indirect confirmation by displaying improvement or worsening that correlated with disease regression or progression. Thoraco-abdominal CT scanning more accurately identifies the extent of small cell carcinoma than other imaging procedures. This has important implications for reporting results by extent of disease. In addition, CT more accurately identifies the magnitude of intrathoracic primary and nodal tumors, which may influence the choice and conduct of local treatment--surgery and/or radiation therapy--in combination with systemic chemotherapy.

Sequencing of drugs and radiation. The integrated alternating regimen

The association of radiotherapy (RT) and chemotherapy (CT) constitutes one of the main avenues for research in therapeutic oncology. This association has two aims: (1) increase in control rate of primary tumor (this requires either the potentiation of one of the two modalities by the other or the additivity of their effect on tumor cells without a parallel increase in the toxic effects on critical normal tissues); (2) spatial cooperation (RT being used for the control of the primary tumor or of the sanctuaries, and CT for the control of the disseminated disease). In these two strategies, RT and CT should be given up to full doses in order to be effective. The main risk is an increase in the number and severity of the early and late side effects. To circumvent this problem, two possibilities are being explored: (1) use of drugs without serious toxic effects on those critical tissues which are included in the irradiated volume; and (2) avoidance of concomitant administration and introduction of a sufficiently long-time gap between the completion of one modality and initiation of the other. However, in such sequential treatment, a delay of CT until after the completion of RT, or an interruption of CT cycle during the course of RT, allows the occult metastases to increase in size; a similar delay in initiation of RT is also detrimental, as drugs are often not effective on bulky tumors. Moreover, under CT, the cells which are resistant to the cytotoxic drugs may disseminate and initiate chemoresistant metastases. Taking these disadvantages into account, a treatment protocol was proposed in 1980 in which CT and RT are given alternately, without undue delay. Chemotherapy is started with the usual scheduling of one cycle every month. Radiotherapy courses are interdigitated between CT cycles. Each course is initiated 1 week after interrupting CT and continued until 1 week before beginning the subsequent cycle of chemotherapy, and so on until completion of RT. Such split-course RT should have an effect on a tumor comparable to that of a conventional fractionation. This protocol has been used on 24 patients with non-Hodgkin's lymphoma (NHL) of diffuse histology, and 63 patients with small cell carcinoma of the lung. The 2-year relapse-free survivals are promising (in clinical stage II NHL of diffuse histology, 75%; and in small cell lung carcinomas, 33%).(ABSTRACT TRUNCATED AT 400 WORDS)

Current status of therapy for small cell carcinoma of the lung

Small cell carcinoma of the lung (SCCL) is distinguished from other types of lung cancer by its propensity for early development of distant metastases and its rapidly fatal clinical course in the absence of treatment. The introduction of chemotherapy into the management of SCCL has led to a four- to five-fold improvement in median survival and to the cure of a small proportion of patients with this disease. Employment of three- or four-drug regimens with or without chest irradiation in moderately intensive doses for periods of 12 months or less has proven to be the optimal therapeutic strategy with currently available agents. Despite these substantial gains, it is obvious that the vast majority of SCCL patients are continuing to die from their cancer, and a slowing in the pace of treatment advances has become apparent over the past 5 years. This article reviews current areas of active clinical investigation in SCCL and some information developed in the cell biology laboratory that may have eventual application in the clinic.