The role of surgery in N2 lung cancer

Induction chemotherapy for stage IIIA unresectable non-small cell lung cancer: the Toronto experience and an overview

Thirty-nine patients with mediastinoscopy stage IIIA, N2 non-small cell lung cancer received two cycles of MVP (mitomycin C, vindesine, cisplatin). Responders underwent thoracotomy for resection and two further courses of MVP. Overall response rate was 64% (25/39) with three complete and 22 partial responses. Twenty-two patients were resected, which included radical mediastinal node dissection. Eighteen resections were complete and four were incomplete. Pathologically, three patients (7.7%) had no remaining tumor. Toxicity included two postoperative deaths with B-P fistula, mitomycin pulmonary toxicity in two patients, and four septic deaths. Twenty-eight patients have died, 20 with recurrent or progressive disease. Of the 18 patients completely resected, eight have recurred with a median time to recurrence of 20.6 months. Sites of recurrence include two locoregional, five distant (two in brain) and one in both. Median survival of the entire 39 patients is 18.6 months, with a three year survival of 26%. The median survival for those patients completely resected was 29.7 months with a 3-year survival of 40%.

Surgical treatment for higher stage non-small cell lung cancer

Locally advanced lung cancer (stage IIIa, IIIb) in which the primary tumor is proximal (T3) or has invaded adjacent structures (T3) or organs (T4) or in which mediastinal lymph nodes are involved (N2, N3) worsens the prognosis significantly. However, in stage IIIa (T3 or N2), when surgical treatment results in total removal of the primary tumor and involved lymph nodes, there still is a reasonable chance for ultimate cure. On the other hand, total excision can be very rarely performed in T4 or N3 tumors. Therefore, this group (stage IIIb) usually indicates unresectability. Disseminated lung cancer with distant metastasis (stage IV) is still considered to be incurable. Nevertheless, solitary metastatic sites (M1), especially brain, have been treated on occasion by resection of the primary tumor and removal of the solitary metastasis. This appears to improve median survival and does yield 5-year survival in selected patients. The results after surgical treatment in these patients with higher stage lung cancer reported over the last 10 years are reviewed.

Survival after resection of stage II non-small cell lung cancer

From 1973 to 1989, 214 patients with stage II non-small cell lung cancer were treated by resection and complete mediastinal lymph node dissection. There were 116 adenocarcinomas and 98 squamous cancers. There were 35 T1 N1 and 179 T2 N1 tumors. Whereas T1 tumors were mainly adenocarcinomas (83%), this difference was not apparent in T2 lesions. Regardless of histology, half of the patients had a single involved N1 lymph node. Lobectomy was performed in 68% of the patients, pneumonectomy in 31%, and wedge resection or segmentectomy in 1%. Lobectomy was sufficient to encompass all disease in 34 of 35 T1 N1 tumors. Only 48 patients (22%) received postoperative external irradiation and 11 patients (5%) received chemotherapy. The overall 5-year disease-free survival was 39%. The best survival rates were in patients who had a single node involved and tumors 3 cm or less in diameter (48%). The pattern of recurrence differed by histology. Local or regional recurrence was more frequent in patients with squamous carcinoma whereas distant metastases were more commonly seen in adenocarcinomas (87%) with brain as the most frequent site (adenocarcinoma, 52%; squamous, 34%). It is concluded that in stage II carcinomas, resection remains the treatment of choice, that mediastinal lymph node dissection provides the most accurate staging, and that the best adjuvant treatment to improve survival is yet to be determined.

Prognostic significance of computed tomography in resected N2 lung cancer

We reviewed 124 patients from 1982 to 1988 who had a resected primary non-small cell lung cancer metastatic to mediastinal (N2) lymph nodes and a preoperative assessment of the mediastinum with computed tomography of the chest. Sixty-three patients studied had computed tomographic evidence of mediastinal lymph node enlargement. In these patients the survival at 5 years was only 6.6%, compared with the 5-year survival of 13.5% in 61 patients in whom the mediastinum was normal. Plain chest roentgenography with evidence of mediastinal adenopathy did not predict a poorer outcome. In addition, patients with tumors located in the left upper lobe were found to have an improved survival. These patients had a 5-year survival of 20.8%. Tumor histology, central location of the tumor, extranodal extension, and type of resection did not result in a significant survival difference.

Combined-modality therapies for non-small cell lung cancer

Regionally advanced stage III non-small cell lung cancer (NSCLC) accounts for nearly 40% of all presentations of NSCLC. In the past, such patients received radiotherapy alone, but the median and long-term survival durations were disappointingly poor. Past attempts at combining chemotherapy and radiation were also disappointing, and were troubled by low doses of radiation or orthovoltage equipment or both. Recently, cisplatin-containing regimens have shown some efficacy in stage IV disease. The response rate for these combinations in stage III disease is nearly double that in stage IV disease. The greater response in stage III has led to a series of trials of sequenced chemotherapy and radiotherapy for treatment of regionally advanced (unresectable stage IIIA and IIIB) NSCLC. Several randomized trials have now shown a statistically significant advantage for the combined modality over radiation alone regarding time to treatment failure, median survival duration, and percent of long-term survivors. Other trials have focused on the concurrent use of chemotherapy and radiotherapy. Several pilot studies have suggested that concurrent cisplatin plus chest irradiation can produce apparently beneficial results with respect to local control and are the subject of ongoing clinical trials. At the University of Maryland Cancer Center, we have combined weekly carboplatin 100 mg/m2 with concurrent chest irradiation. The preliminary results are very encouraging. The toxicity of this treatment program is very manageable, and preliminary data suggest excellent local control and survival. Other pilot studies have suggested that combination chemotherapy with concurrent radiotherapy is also technically feasible.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary lung cancer in young patients: a study of 82 surgically treated patients

The aim of this study was to evaluate the prognosis for surgically treated young patients with primary lung cancer, a prognosis generally considered to be very poor. Eighty-two patients less than 40 years of age were operated on at Marie-Lannelongue Hospital between 1982 and 1990. There were 72 male and 10 female patients. Ten patients (12%) had never smoked, whereas 48 patients (59%) had smoked for more than 20 pack-years. The lung cancer was asymptomatic in 27 patients (33%) and symptomatic in the others. Adenocarcinoma was found in 42% of the patients, epidermoid carcinoma in 28%, mixed cell carcinoma in 16%, small cell carcinoma in 8.5%, and undifferentiated large cell carcinoma in 6%. Among the 69 resected tumors, 22 were stage I, ten were stage II, 32 were stage IIIa, and five were stage IIIb. The resection was considered complete and curative in 56 patients (68%) and noncurative in 26 (32%) either because of an incomplete resection (12 in stage IIIa; 1 in stage IIIb) or because of an exploratory thoracotomy only (13). The overall actuarial 5-year survival rate was 41%, and the actuarial 5-year survival for patients who had a complete resection was 56%. The actuarial 5-year survival rates were as follows: patients in stage I, 70%; stage II, 54%; stage IIIa, 28%; stage IIIb, 0%; and patients having exploratory thoracotomy only, 18%. These survival rates are similar to those of patients older than 40 years with similar stages of disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Preoperative chemotherapy and radiation therapy for stage IIIa carcinoma of the lung

Thirty-six patients with stage IIIa histologically proven non-small cell carcinoma (T3 N2 or T2 N2) underwent concomitant radiation therapy and chemotherapy before pulmonary resection. The therapy consisted of two cycles of continuous infusion of cis-platinum, 25 mg.m-2.day-1 (days 1 through 4) every 4 weeks and concomitant irradiation, 55 Gy, of the tumor and mediastinum. Two to 3 weeks after treatment, the patients were reevaluated for thoracotomy and pulmonary resection. Five patients were found to have unresectable lesions. Thirty-one patients had complete resection, 27 by radical pneumonectomy and 4 by radical lobectomy, giving a resectability rate of 86%. Complete sterilization of lung tumor and mediastinal nodes proven histologically was achieved in 10 patients (28%) and 17 patients (47%). The 3-year survival rate is 61.7% for patients who had resection. Median follow-up is 27 months (range, 6 to 61 months). The preliminary study indicates that preoperative cis-platinum and concomitant radiation therapy is tolerated, appears to increase resectability, and may improve survival in patients with stage IIIa lung cancer.

A flow cytometric study of non-small cell lung cancer classified as T1N0

Surgical resection currently offers the best chance for cure of non-small cell lung cancer but its efficacy is limited by subsequent tumor recurrence. Even the most favorable cancers (T1N0 tumors) recur 20% to 30% of the time within 5 years and there is currently no way to anticipate precisely which tumors will recur. To test whether DNA flow cytometric study might be useful in this regard, the authors performed a retrospective case-control study of 102 tumors (51 recurrent cases and 51 controls) from a prospective registry of patients with completely resected, meticulously staged T1N0 non-small cell carcinomas. Unbiased relative hazard ratios of recurrence were estimated for ploidy and proliferative rate, as well as for tumor histologic type and clinical variables. Ploidy abnormalities were slightly more common among cases (67%) than controls (57%) but this difference was not statistically significant. Estimation of proliferative rates was possible for 85 tumors but there was no significant difference between cases and controls and proliferative rates were not prognostic of recurrence. In multivariate analyses, the observed predictive value for each of the flow cytometric parameters was modest at best and smaller than that seen for tumor histologic type. These results suggest that flow cytometric analysis has limited value in guiding management of patients with early stage non-small cell carcinoma.

Induction chemotherapy for non-small cell lung cancer with clinically evident mediastinal node metastases: the role of postoperative radiotherapy

Survival for clinical Stage IIIa (T1-3, N2) non-small cell lung cancer is very poor because of poor local disease control and systemic spread. To address these shortcomings, we initiated a treatment program with induction chemotherapy, surgery, and postoperative radiation reserved for patients with residual disease at thoracotomy. Between 1984 and 1986, 41 patients with clinically evident N2 disease were treated with induction chemotherapy followed by resection and the selective use of intraoperative brachytherapy. All patients with tumor in the resection specimen received two cycles of chemotherapy and 15 patients received radiation therapy. With a median follow-up of 5.4 years, overall survival is 27% at 3 years, and 12% at 5 years. Despite the adverse selection process median survival is 19 months for patients receiving postoperative radiation therapy, and 22 months for the more favorable patients not requiring radiation therapy, supporting the selective use of postoperative radiation in this setting. In summary, this treatment has yielded good median survival and long-term survival for some of the patients. However, the ultimate value of this approach can only be determined by prospective trials which compare it to standard therapy.

Mediastinal nodal involvement and the prognosis of non-small cell lung cancer

We evaluated the effect of mediastinal lymph node metastasis on survival in 233 non-small cell lung cancer patients (N2 disease in 199 patients and N3 disease in 34 patients). Of the 199 patients with N2 disease, 144 underwent curative resection. The five-year survival rate of these 144 patients was 20.3 percent, which was significantly better than that of either the noncuratively resected N2 group or the N3 group. Nodal metastases in the curatively resected patients involved superior and inferior mediastinum irrespective of the location of the primary tumor. Patients with right-sided N2 lesions and metastases to the superior mediastinum had a worse survival than those with metastases to the inferior mediastinum. In contrast, patients with left-sided N2 lesions metastasizing to the inferior mediastinum had a significantly worse survival than those with lesions metastasizing to the superior mediastinum. Patients with single-level metastases had a significantly better survival rate than those with multilevel metastases. Subcarinal nodal involvement had an unfavorable effect in case of single-level metastasis, but did not affect the survival in cases of multilevel metastases. Our present study indicated that the survival of patients with N2 disease was affected by the operative radicality, by the number of levels of metastases, and also by the location of the nodal involvement. It seems appropriate that extensive mediastinal dissection should be performed irrespective of the location of the primary tumor.

Aggressive surgical intervention in N2 non-small cell cancer of the lung

An aggressive attitude toward surgical treatment was taken in patients with N2 non-small cell lung cancer in the past 10 years. Computed tomographic scanning was employed in the diagnosis of N2 disease, and had a true-positive rate of 57%. Among patients with N2 disease detected by computed tomographic scanning, surgical intervention was attempted except for those with unresectable disease. Of 190 patients with clinical N2 disease, 115 underwent surgical exploration: 9 patients had only an exploratory thoracotomy, 53 patients underwent a curative operation, and 53 had a noncurative operation. The overall 5-year survival rate of these patients was 16% and that of curatively resected patients was 20%. There were 47 patients whose N2 disease was not recognized before operation. The 5-year survival rate of this group was 20% overall and 33% in curatively resected cases. The overall 5-year survival rate of patients with N2 disease who underwent resection (106 with clinical N2 disease and 47 with clinically unrecognized N2 disease) was 17%, and that of the 84 patients undergoing curative operations was 24%. An aggressive attitude toward surgical intervention can be advocated for patients with N2 disease on the basis of our present results.

Endoscopic ultrasound examination for mediastinal lymph node metastases of lung cancer

Among patients with primary lung cancer who were admitted to the National Cancer Center Hospital from July 1987 to April 1988 for surgical treatments, 132 underwent preoperative transesophageal endoscopic ultrasound examination (EUS) on mediastinal lymph nodes. Of the 132 patients, 101 were pathologically evaluated and studied in this article. A GF-UM2 radial scanner with 7.5-MHz (Olympus Co Ltd) was used for image examination. The lymph nodes were diagnosed as positive for metastasis when they had thickened images, clear contours, and low echoing images of fusion or lobulation. The results obtained from 509 sites were as follows: sensitivity, 53.6 percent; specificity, 97.5 percent; positive predictive accuracy, 77.1 percent; negative predictive accuracy, 93.1 percent; and overall accuracy, 91.6 percent. The sensitivity rate was 80.6 percent excluding the result of the right superior mediastinal lymph nodes that were difficult to examine for anatomic reasons. Although EUS was considered to be an excellent method in diagnosing lymph node metastases, it had a blind angle in the field. More accurate diagnoses of mediastinal lymph node metastases could be achieved by using EUS and computed tomography (CT) together.

[Correlation of lymph node size and metastatic involvement of lymph nodes in bronchial cancer]

For preoperative staging in lung cancer mediastinoscopy is in competition with X-ray, tomography, and computer-tomography (CT). Many authors certify a high sensitivity and specificity to CT in staging lung cancer preoperatively by measuring the diameter of the hilar and mediastinal lymph nodes. In this study we measured the diameter of 162 lymph nodes from 83 patients postoperatively. In view of staging we found no sufficient correlation between the diameter of the lymph nodes and their infiltration by cancer cells. Even 35.7% of the nodes with a diameter of more than 2 cm were not infiltrated. The data support the opinion that CT alone is not sufficient for preoperative staging in lung cancer.

Computed tomography in bronchogenic carcinoma

As was indicated at the beginning of this review, a concensus does not exist regarding many aspects of the use of CT in evaluating bronchogenic carcinoma. When and how CT is used, therefore, becomes a function of the beliefs of the physician caring for the patient. The radiologist must be familiar with this philosophy to be able to advise when CT will be of value. Despite all of the variables considered on the preceding pages, there are some facts. (1) Normal mediastinal lymph nodes may be larger than 1 cm in maximal transverse diameter; the majority are not. (2) An enlarged node (independent of definition) need not harbor metastases. Histologic proof is necessary, especially if this information will preclude surgery. (3) CT less frequently offers usable information in small peripheral cancers. The use of CT in peripheral cancers is very much dependent on the surgeon's philosophy. (4) Important information for patient care is more frequently obtained in patients with central lesions or peripheral lesions associated with abnormal hili or mediastinums. This is also closely related to surgical philosophy. (5) Prediction of either chest wall or mediastinal invasion is treacherous and should only be diagnosed when the findings are certain.

Surgical treatment of non-small cell lung cancer by stage

Resection is the treatment of choice for stage I and II non-small cell lung carcinoma. The 5-year survival following resection is 72% in stage I carcinoma and 49% in stage II carcinoma. Resection alone or combined with radiation and/or chemotherapy is also indicated in some patients with stage IIIa disease. The 5 year survival with resection is 56% in tumors invading chest wall (T3N0), 30% in superior sulcus tumors, 30% in patients with N2M0 disease, and 36% in patients with tumors in proximity to carina. Surgery is of very limited value in patients with tumors invading the mediastinum and in patients with stage IIIb or stage IV disease. Details of case selection in each treatment category are presented.

Significance of extramucosal residual tumor at the bronchial resection margin

Extramucosal microscopic residual disease (MRD) at the bronchial resection margin was identified in 45 (1.6%) of 2,890 patients who underwent resection of primary non-small cell lung cancer between 1975 and 1985. In 9 of these patients, residual tumor was confined to submucosal lymphatics, whereas in the other 36, MRD was found in peribronchial soft tissue. All patients underwent complete mediastinal lymphadenectomy. Three patients had stage I disease, 3 had stage II, 33 had stage IIIa, 4 had stage IIIb, and 2 had stage IV. Recurrent disease developed in 34 (81%) of the evaluable patients; the recurrence was local in 11 (32%). Median time from operation to diagnosis of local recurrence was 8 months. Sixty percent of the recurrences in the N0 group were local, and only 23% of those in the N2 group were local. Extramucosal MRD is most frequently associated with advanced-stage disease. Postoperative therapy had no effect on the development of recurrent disease. We found no difference in survival between patients whose initial site of recurrence was local as opposed to distant. Median survival after the identification of either local or distant recurrence was 5 months. The finding of extramucosal MRD identifies a subset of patients with a poorer prognosis compared with those with clear resection margins.