Small cell carcinoma of the lung

Bone Marrow Biopsy in the Staging of Small Cell Lung Cancer

From April 1982 to December 1987, 71 patients with small cell lung cancer entered a randomized clinical trial, and underwent bone marrow biopsy (BMB) as part of staging procedures. We identified 8 patients (11 %) with bone marrow metastases, 6 with extensive disease independently of BMB, and 2 with extensive disease on the basis of the BMB only. BMB determined a change in the stage in only 3 % (2/71) of the cases. No differences were found in the hematological parameters of the patients with or without bone marrow metastases. The median survival of the patients with bone marrow involvement was the same (41 weeks) as those with extensive disease but without bone marrow involvement. We conclude that unilateral BMB without aspiration detects a substantial proportion of bone marrow metastases in patients with extensive disease. This fact does not worsen the prognosis. A small proportion of patients with apparently limited disease has bone marrow involvement. The technique therefore contributes, to a small extent, to the definition of the clinical stage of the disease. However, bone marrow involvement is an important data of natural history, and therefore new methods to better assess this peculiar site of the disease are needed.

Combination chemotherapy with low doses of weekly Carboplatin and oral Etoposide in poor risk small cell lung cancer

Sixty patients with poor prognostic features, either with extensive disease (ED) or limited disease (LD) small cell lung cancer (SCLC), were treated on an out-patient basis with Carboplatin 80 mg/m2 weekly for 3 weeks and oral Etoposide, at a dose of 100 mg, every other day for 21 days. The treatment was repeated every 5 weeks. Responding patients with LD were also treated with thoracic irradiation and those who achieved complete response (CR) received prophylactic cranial radio-therapy. The overall response rate (RR) was 32.1% with 8.9% CR. The responses were better for LD (RR 58.3%, CR 25%, partial response, PR 33.3%), than those for ED (RR 25%, CR 4.5%, PR 20.5%). The median time to progression (TTP) was 4.8 months and the median survival 5.5 months. These poor results could be attributed to the bad performance status and the presence of visceral and brain metastases in this group of patients. The results could also be due to the lower maximum concentration (Cmax) and higher T1/2 of Etoposide, as measured in the blood and urine probably due to the modified regimen used in our study and to the organ insufficiency in this selected group of patients. Although, toxicity was generally mild and manageable, two toxic deaths occurred. In conclusion, this regimen appears to have a lower efficacy in terms of response and survival than that obtained in other studies using Cisplatin or Carboplatin plus Etoposide in a similar way. Therapy with this regimen, though less toxic, may not be a reliable alternative in elderly patients with visceral metastases and ECOG performance status > or = 2.

Combinational effects of vitamin D3 and retinoic acid (all trans and 9 cis) on proliferation, differentiation, and programmed cell death in two small cell lung carcinoma cell lines

The effects of a combination of vitamin D3 [1,25(OH)2D3] and retinoic acid (RA) on proliferation, differentiation, and apoptosis of the human small cell lung carcinoma (SCLC) cell lines NCI-H82 and NCI-H209 were evaluated. Cell proliferation was inhibited by 1,25(OH)2D3 and RA alone. The combination of 1,25(OH)2D3 and the cis form of retinoic acid resulted in an additive decrease in cell proliferation and the induction of apoptosis in various concentrations. Moreover, 3H-thymidine incorporation was inhibited and the number of viable cells was decreased. The characteristics of the apoptotic cells were examined and confirmed by morphologic analysis, light and electron microscopy, and fluorescence detection. It was concluded that 1,25(OH)2D3 and RA exert additive effects on the inhibition of proliferation and the induction of apoptosis in both the NCI-H82 and the NCI-H209 SCLC cell lines. This finding has important implications for the use of retinoids and 1,25(OH)2D3 in cancer prevention and in the therapy of small cell lung carcinoma.

Effects of retinoic acid (all-trans and 9-cis) on tumor progression in small-cell lung carcinoma

The two stereoisomers of retinoic acid (RA), all-trans and 9-cis-RA, are regulators of cell proliferation, differentiation and apoptosis. In this study, the aim was to evaluate the effects of all-trans-and 9-cis-RA on cell growth, proliferation, and on the induction of apoptosis in the human small cell lung carcinoma (SCLC) cell lines NCI-H82 and NCI-H209. The application of various concentrations of all-trans and 9-cis-RA were able to inhibit cell growth and proliferation. Moreover, 3H-thymidine incorporation was inhibited and the number of viable cells decreased, suggesting that all-trans-RA and 9-cis-RA can inhibit cell proliferation in a dose dependent manner. Morphological examinations (light, electron and fluorescence microscopy) demonstrated that both retinoids had profound effects on the induction of apoptosis. Our investigation also showed that, compared to all-trans-RA, 9-cis-RA is a stronger inducer for the inhibition of cell growth and proliferation and that it is more effective in the induction of apoptosis in small cell lung carcinoma cells in culture.

Correlation of in vitro drug sensitivity testing results with response to chemotherapy and survival: comparison of non-small cell lung cancer and small cell lung cancer

Clinical protocols for small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) were devised to prospectively select individualized chemotherapy based on in vitro drug sensitivity testing (DST) of cell lines derived from the patient's SCLC tumor cell lines or the patient's fresh NSCLC tumor. DST data derived from SCLC tumor cell lines were available for 33/115 (29%) patients. The DST-selected chemotherapy regimen was administered to 21 (18%) patients, or 64% of patients with DST. In SCLC< the DST-selected chemotherapy was administered either during weeks 13-24 following 12 weeks of etoposide/cisplatin, or at relapse after complete response to etoposide/cisplatin. Several parameters of in vitro drug sensitivity were significantly associated (two-sided P < 0.05) with clinical response to primary therapy and also with response to the DST-selected chemotherapy regimen, but were not associated with survival (P = 0.24). Five patients treated with their DST-selected chemotherapy attained a complete or partial response, compared to 5 of 68 who received an empiric regimen (P = 0.057). A total of 36/165 (22%) NSCLC patients had DST successfully completed. These results directed management for 21/96 (22%) patients who eventually received chemotherapy, or 58% of patients with DST. Response to chemotherapy for the patients treated prospectively with their DST-selected chemotherapy regimen (2/21; 9%) was not significantly different than the response rate for patients treated empirically with etoposide/cisplatin (10/69; 14%) in the absence of in vitro results to direct chemotherapy (P = 0.73). There was no difference in survival by treatment group for the NSCLC patients. The correlation between in vitro and clinical response was not significant for any individual drug or for all drugs considered together, illustrating the poor predictive value of in vitro testing with currently available chemotherapy in NSCLC.

Identification of novel regions of altered DNA copy number in small cell lung tumors

Identification of the genetic alterations that occur in tumors is an important approach to understanding tumorigenesis. We have used comparative genomic hybridization (CGH), a novel molecular cytogenetic method, to identify the gross DNA copy number changes that commonly occur in small cell lung cancer (SCLC). We analyzed ten SCLC tumors (seven primary tumors and three metastases) from eight patients. We found frequent increases in DNA copy number on chromosome arms 5p, 8q, 3q, and Xq and frequent decreases in copy number on chromosome arms 3p, 17p, 5q, 8p, 13q, and 4p. The increase in copy number at 8q24 (MYC) and decreases at 17p13 (TP53), 13q14 (RB), and 3p have previously been identified in SCLC with other methods. Many of the other regions in which we detected common copy number changes have not been reported to be regions of common alteration in SCLC tumors. Comparison of copy number changes between a primary tumor and a metastasis from the same patient showed that they were more closely related to each other than to any of the other tumors. The results of direct CGH analysis of SCLC tumors reported here confirm the existence of copy number changes that we identified previously by using cell lines.

Recent advances in radiation oncology

Radiotherapy remains an important component of the management of malignant disease. Especially when combined with cytotoxic chemotherapy, limited surgical excision, or both, irradiation has been shown to control disease in the primary site and regional nodes without the need for surgical extirpation as frequently as in past years. New developments in three-dimensional treatment planning and the precise delivery of high-dose radiation promise to increase the benefit of radiation treatment. Finally, molecular studies of the cell's response to radiation and the phenomena of DNA damage and repair are providing explanations for heretofore unexplained radiobiologic observations. Such research is laying the groundwork for targeted manipulation of the cell's response to radiation, which will be tested in the near future.

Investigation of new agents in small-cell lung cancer

The identification of new agents active against small-cell lung cancer (SCLC) remains a high priority for clinical investigators. Recently, 2 very different approaches have been used to evaluate new agents in this disease. Some groups have opted to test new agents in previously untreated patients with extensive-stage SCLC, and the second approach is to continue to test new agents only in previously treated patients. Regardless of which method is used, it appears that new-agent activity can be assessed in either previously treated or untreated SCLC patients without compromising the therapeutic gains of the past 2 decades, provided proper patient selection guidelines are employed.

Results of operation without adjuvant therapy in the treatment of small cell lung cancer

The role of surgery in the treatment of small cell lung cancer remains a subject of debate. We carried out a retrospective review of 87 patients with small cell lung cancer referred to one surgeon for staging and treatment. Thirty patients (34.5%) were deemed suitable for thoracotomy. Fourteen patients had stage I disease, 5 patients had stage II disease, and 11 patients had stage III disease. Twenty-eight of the 30 patients (93.3%) went on to have surgical resection. The actual overall 5-year survival in all patients who underwent thoracotomy was 43.3%. The actual 5-year survival for patients in stages I and III was 57.1% and 55.5%, respectively. No patients with stage II disease survived 5 years. We conclude that there is a small group of patients with small cell lung cancer in whom, with careful preoperative staging, the prospects of cure by operation are similar to those with non-small lung cancer.

Combination chemotherapy with vincristine, epirubicin and cyclophosphamide in small cell lung carcinoma. Polish Lung Cancer Cooperative Group

The aim of this prospective study was to assess the activity of a combination of vincristine, epirubicin and cyclosphosphamide (VEC) in previously untreated patients with limited small cell lung carcinoma (SCLC) and to delineate the feasibility of dose escalation for epirubicin in this regimen. The chemotherapy schedule included cyclophosphamide, 1000 mg/m2, vincristine, 1 mg/m2 and escalating doses of epirubicin: 50 mg/m2, 70 mg/m2 and 90 mg/m2; respectively in three consecutive groups of patients. Drug cycles were repeated every 3 weeks. 118 patients from eight institutions were enrolled in this study between February 1986 and March 1989. Objective tumour response was observed in 81 of 116 evaluable patients (70%) including 25 patients (22%) who achieved a complete remission. Responding patients received thoracic radiation after the fourth cycle of chemotherapy. The median duration of response was 30 weeks and the median duration of survival was 52 weeks. There were no significant differences in treatment results between the consecutive groups of patients. The regimen was well tolerated for all doses of epirubicin. The main toxicities included alopecia (96%), nausea and vomiting (81%) and leukopenia (44%). Grade 4 haematological toxicity was observed in 3 patients (2.6%). No significant epirubicin dose-dependent side effects, except for mucositis were observed.

A phase II trial of cisplatin and prolonged administration of oral etoposide in extensive-stage small cell lung cancer

Etoposide is a schedule-dependent agent with greater activity against small cell lung cancer (SCLC) when a given dose is administered over several days compared with a 1-day administration of the same dose. In an attempt to capitalize on the schedule dependency of etoposide, 22 previously untreated extensive-stage SCLC patients were given cisplatin (100 mg/m2 on day 1) plus 21 days of low-dose, oral etoposide (50 mg/m2/d). Chemotherapy was repeated every 28 days for four cycles. Complete blood counts were monitored weekly, and etoposide was discontinued if either the leukocyte or platelet count dropped below 2000/microliters or 75,000/microliters, respectively. All 22 patients were evaluable for response; 18 had either a complete (9%) or partial response (73%), an overall response rate of 82% (95% confidence interval, 62% to 93%). The median response duration was 7 months, and the median survival was 9.9 months (range, 1 to 17+ months). Sixteen (73%) patients received all planned cycles of etoposide. In Cycle 1 of chemotherapy, the median leukocyte nadir was 2700/microliters (range, 100 to 6300/microliters), and median platelet nadir was 180,000/microliters (range, 51,000 to 397,000/microliters). Life-threatening leukopenia (less than 1000/microliters) was rare (3 of 74 cycles). There were three treatment-related deaths, only one of which was associated with neutropenia. One patient had mild renal insufficiency that resolved after discontinuation of therapy. Alopecia was observed in all patients, but other nonhematologic toxicities were uncommon. A randomized study is necessary to determine if this schedule of cisplatin and etoposide administration is superior to more standard methods. However, these data do not indicate a major survival benefit will be derived from increasing the duration of etoposide administration when used in combination with cisplatin given every 28 days.

Extrapulmonary and pulmonary small-cell carcinoma: tumor biology, therapy, and outcome

Extrapulmonary small-cell cancer is a distinct clinicopathological entity from small-cell anaplastic carcinoma of the lung. Approximately 1,000 cases have been projected annually in the United States, which represents an overall incidence of between 0.1% and 0.4% of all cancer. Not surprisingly then, little information is available regarding the treatment of this disease, which presents a challenge to the clinician when it is regionally confined. The majority of patients with extrapulmonary small-cell neoplasms have only been treated with local modalities of therapy, surgery, radiation, or a combination of both. Prolonged survival is not infrequent, which is in contrast to the experience for small-cell lung cancer and surprising given our current systemic approach to patients with this disease. This report will summarize the similarities and differences in biology, natural history, and clinical characteristics of patients with extrapulmonary small-cell cancer and small-cell anaplastic carcinoma of the lung. The histogenesis of small-cell cancer is briefly reviewed. A general therapeutic approach to patients with small-cell lung cancer is reported. Lastly, recommendations for therapy of patients with regionally confined extrapulmonary small-cell cancer by primary site are outlined.

Current status of etoposide in the management of small cell lung cancer

Etoposide is a schedule-dependent drug with excellent activity against small cell lung cancer (SCLC). Single-agent etoposide achieves overall response rates ranging from 15% to 84%, depending on the schedule of drug administration and the characteristics of the treated population. The route of etoposide administration (intravenous versus oral) has little impact on response rate, provided appropriate dose adjustments are made for oral therapy. In combination with other active agents, etoposide has proven particularly effective in the management of SCLC. Etoposide can be substituted for doxorubicin or vincristine in the cyclophosphamide, doxorubicin, and vincristine (CAV) regimen without loss of efficacy. The etoposide and cisplatin (EP) combination is thought to be synergistic and has proven to be an effective salvage regimen for CAV failures. A regimen that alternates CAV and EP has been found by some investigators to be modestly more effective against SCLC than CAV alone; however, EP alone may be as useful as an alternating regimen. Most studies to date have demonstrated that EP induction is at least as effective as any other standard induction regimen. However, EP has the potential advantage of being more easily integrated with thoracic radiation therapy (RT). This is particularly important in limited-disease patients: two recent pilot studies employing EP induction with hyperfractionated thoracic RT yielded 2-year survival rates of greater than 50%. These promising results are being evaluated further in an ongoing Phase III trial in the United States. The available data indicate that etoposide is one of the most active agents against SCLC and therefore should be included as a component of induction therapy in all patients. New schedules of etoposide administration warrant further study.

Evaluation of high-dose etoposide combined with cisplatin for treating relapsed small cell lung cancer

The synergism of combined high-dose etoposide with standard dose cisplatin (HD-EP) was evaluated in 20 patients who had relapsed after treatment of small cell lung cancer. Each patient was given etoposide at 500 mg/m2/day on days 1 to 3 and cisplatin at 80 mg/m2 (two patients given 120 mg/m2) on day 1; autologous bone marrow was not transplanted. Five patients were given recombinant human granulocyte colony-stimulating factor (rhG-CSF, 50 micrograms/m2) in an attempt to reduce HD-EP induced neutropenia. The overall response was 50% (9 of 18); one complete response (6%), eight partial responses (44%), seven no change (39%), and two progressions of disease (11%). Of the 18 evaluable patients, 12 had been treated with regimens of conventional doses of etoposide with conventional doses of cisplatin or carboplatin, and of these, five (42%) achieved a partial response. The median duration of response was 8.4 weeks (range, 5.3 to 17.7) and the median survival time was 20.3 weeks (range, 1.6 to 91). All of the patients developed severe myelosuppression; rhG-CSF did not shorten the period of the leukopenia. Mucositis and liver dysfunction were the major nonhematologic manifestations of toxicity. Two treatment-related deaths resulted from sepsis. These results suggest that the activities of high doses etoposide with standard doses of cisplatin are synergistic against small cell lung cancer.

Combination chemotherapy with or without radiation therapy in small cell lung cancer. An analysis of a 5-year follow-up

From January 1978 to March 1984, a series of 159 patients with newly diagnosed small cell lung cancer (SCLC) was treated with combination chemotherapy with or without chest radiation at the Osaka Prefectural Habikino Hospital. By March 31, 1989, ten patients (6.3%) had survived for 5 years or more after the initial chemotherapy, including nine of 95 patients (9.5%) with limited disease and one of 64 patients (1.6%) with extensive disease. All these 5-year disease-free survivors, except for one patient whose response could not be assessed by chest radiograph because of radiation fibrosis, had a complete response. Nine of the 71 patients (12.7%) treated with combination regimens containing doxorubicin survived 5 years or more, and only one of the 88 (1.1%) treated with regimens without doxorubicin had long-term survival (P less than 0.01). The sex, performance status (PS), and chest radiation after systemic chemotherapy did not correlate statistically with long-term survival (P greater than 0.05). Three of the ten patients died free of SCLC. Two of the ten patients (20%) developed second malignancies and died. The remaining patient died of pneumonia. The Cox regression analysis identified the PS and doxorubicin-containing regimens as important factors indicating improved survival. Combination regimens containing doxorubicin have, therefore, been found to be very effective in improving survival and achieving long-term survival.

Correlation of in vitro drug sensitivity testing of long-term small cell lung cancer cell lines with response and survival

In vitro drug sensitivity testing (DST) of long-term cultures from small cell lung cancer (SCLC) tumours was correlated with response and survival after four cycles of etoposide and cisplatin. 27 cell lines from 25 patients were tested by the semi-automated MTT assay after a median culture of 29 months. The logs of the IC50 concentrations for etoposide and cisplatin were correlated with each other. For both drugs, median IC50 values of patients with partial or complete responses ("responders") were significantly lower (7-8 fold) than those of non-responders. When survival was plotted according to whether drug IC50 values were in the upper or lower halves, curves for etoposide were significantly different, but those of cisplatin were not. DST of the long-term cell lines by MTT assay was significantly correlated with the Weisenthal dye exclusion assay of earlier passages of the same cell lines. DST of long-term SCLC cultures can predict clinical response and, for etoposide, survival. Disease-oriented panels of carefully selected, continuous, human tumour cell lines can be used to screen new drugs.

Bone marrow involvement in small cell lung cancer. Clinical significance and correlation with routine laboratory variables

Of 129 patients with small cell lung cancer (SCLC) who underwent bone marrow examination for staging, 39 (30%) had bone marrow involvement. Only three of 129 patients (2.3%) had bone marrow involvement as the only site of metastatic disease. When patients with bone marrow metastasis were compared with patients whose bone marrow was normal, there were significant differences in serum levels of lactate dehydrogenase (LDH), glutamic oxalacetic transaminase (SGOT), glutamic pyruvic transaminase (SGPT), alkaline phosphatase (AP), albumin, and sodium (Na). We found no clinically significant difference in survival between patients with extensive disease with or without bone marrow involvement. Serum Na, albumin, SGOT, and uric acid were important prognostic determinants of survival. Based on the results of this study, we do not recommend routine bone marrow examinations in the staging of SCLC.

Cisplatin and etoposide (VP-16) as a single regimen for small cell lung cancer. A phase II trial

Forty-seven consecutive patients with small cell lung cancer (SCLC) were treated with a combination chemotherapy program including 60 mg/m2 of cisplatin (P) on day 1 and 120 mg/m2 of etoposide (E) on day 4, 6, 8, every 21 days. Limited disease (LD) patients, achieving complete response (CR) or partial response (PR) after the three initial courses, received radiotherapy (RT) to the pretreatment primary tumor volume and, those achieving CR, additional RT to the brain. During RT, chemotherapy was administered with 50% dose reduction. Forty-three patients were evaluable for therapeutic response. In the 19 patients with LD, CR was achieved in 63% of patients and the PR rate was 32%. In 24 patients with extensive disease (ED), CR was 34% and PR rate was 54%. Median duration of survival was 66 weeks for LD and 48 weeks for ED. Six patients were disease-free after 2 years. Leucocyte count less than 2000/mm3 was seen in 26% of patients; platelet count less than 50000/mm3 was observed in 9%. Nonhematologic toxicity included universal nausea or vomiting and severe neurotoxicity in 7%. These data indicate that PE combination is a very active front-line regimen in SCLC and could be suggested as one of the reference treatments.

The role of prophylactic brain irradiation in limited stage small cell lung cancer: clinical, neuropsychologic, and CT sequelae

Ninety-four patients with limited stage small cell lung cancer treated between 1981 and 1985 with a regimen including prophylactic brain irradiation (PBI) after combination chemotherapy were assessed for compliance with PBI, brain relapse, and neurologic morbidity. Seventy-seven percent of patients had PBI and of these, 22% developed brain metastases after a median time of 11 months post treatment. The brain was the apparent unique initial site of relapse in 10% of PBI cases but more commonly brain relapse was preceded or accompanied by failure at other sites, especially the chest. Brain metastases were the greatest cause of morbidity in 50% of PBI failures. Twelve of 14 PBI patients alive 2 years after treatment had oncologic, neurologic, and neuropsychological evaluation, and brain CT. All long-term survivors were capable of self care and none fulfilled diagnostic criteria for dementia, with three borderline cases. One third had pretreatment neurologic dysfunction and two thirds post treatment neurologic symptoms, most commonly recent memory loss. Fifty percent had subtle motor findings. Intellectual functioning was at the 38th percentile with most patients having an unskilled occupational history. Neuropsychologic impairment ratings were borderline in three cases and definitely impaired in seven cases. CT scans showed brain atrophy in all cases with mild progression in those having a pre-treatment baseline. Periventricular and subcortical low density lesions identical to the CT appearance of subcortical arteriosclerotic encephalopathy were seen in 82% of posttreatment CT studies, and lacunar infarcts in 54%. Neuropsychologic impairment scores and the extent of CT periventricular low density lesions were strongly associated (rank correlation 0.7, p less than .05). Overall, PBI after intensive combination chemotherapy did not induce gross dementia or neurologic dysfunction but its risk/benefit ratio is not overwhelmingly favorable, with failure to prevent brain relapse in 1/5 patients and subtle but detectable motor findings and neuropsychologic impairment in the majority.

Surgery in small cell lung cancer

Surgery in small cell lung cancer (SCLC) was abandoned in the late 1960s but is currently being cautiously reassessed, after the Armed Forces Asymptomatic Pulmonary Nodule Study demonstrated an unexpectedly prolonged 5-year survival (36%) with surgery. Subsequent prospective studies have reported five-year survival following resection in 22 to 83% of patients with Stage I disease and in 0 to 50% of patients with Stages II and III disease. Ten percent of patients with SCLC may be amenable to this approach. Additional patients may become candidates for resection following intensive combination chemotherapy. The optimal postoperative management remains unsettled. Combination chemotherapy and prophylactic cranial irradiation is recommended following complete resection. Postoperative thoracic irradiation may benefit patients with pathologically involved mediastinal nodes. Correlation of clinical response with our new understanding of the molecular biology of SCLC may further improve our approach to this disease.

Postchemotherapy resection of residual tumor in limited stage small cell lung cancer

To determine the feasibility of post-chemotherapy resection of residual tumor in small cell lung cancer, 24 selected patients with limited-stage disease were evaluated for exploratory thoracotomy. All 24 patients achieved partial or complete clinical response to chemotherapy and were considered adequate medical candidates for surgical resection. Fifteen patients underwent a lobectomy or pneumonectomy, 13 of whom had residual tumor in the resected specimen. Of the nine remaining patients, seven had no tumor found on biopsy at thoracotomy and two had unresectable mediastinal node involvement. No chemotherapy was administered postoperatively in any patient until disease progression or relapse was documented. Median survival for the entire group was 19 months and did not differ according to the surgical procedure performed. Nineteen patients had relapse. Patients undergoing biopsy only recurred locally in six of seven cases a median of five months post-thoracotomy (range one to six months). Two "biopsy only" patients were tumor free at 34+ and 56+ months. Local recurrence was observed in six of 12 resected patients, while six patients experienced only extrathoracic metastases. Median time to recurrence for resected patients was also five months. Four resected patients experienced late recurrence 16 to 36 months postoperatively and were alive with tumor at 29+ to 42+ months. Two resected patients were tumor-free at 13+ and 37+ months. Post-chemotherapy surgical resection was feasible in limited-stage patients and improved local control of disease.

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.