Background and Methods. To validate the new TNM definitions for lung cancer (International Union Against Cancer [UICC]) TNM classification, 4th edition, 1987, the data of 3823 patients were analyzed prospec‐tively in terms of concordance between clinical (TNM) and pathologically confirmed classification (pTNM), the value of the various diagnostic techniques in estimating the pathologically confirmed classification, and the prognostic relevance of the new TNM definitions. Results. With regard to the primary tumor (T), clinical and pathologic classifications were identical in 63%; with regard to lymph node involvement (N), the agreement was 47%; for distant metastasis agreement occurred in 91% of cases and for the stages it occurred in 56%. As to the primary tumor (T), the accuracy of radiography (59%) was nearly identical to that of computed tomography (CT) (58%). Both techniques were less precise in determining the extent of lymph node involvement (CT, correct assessments in 50%; radiography, correct assessments in 43%). The statistically significant differences in the prognosis for the T, N, and M categories and for the stages and the categories of the new R classification could be confirmed. Allowance should be made for the different prognosis between TlNOMO and T2NOMO by the new Substages IA and Ib of Stage I. Conclusions. By the new TNM definitions for bronchus carcinoma, international conformity became feasible and practical, and the improvement of its prognostic relevance provided a more reliable basis for establishing guidelines for individual oncologic concepts. Cancer 1992; 70:1102–1110.

IL-2 secretion at the time of diagnosis represents an independent prognostic factor for survival in SCLC. Although its prognostic value has to be confirmed in a larger group of patients, our results demonstrate that IL-2 secretion may play an important role in diagnosis and treatment of SCLC. Moreover, in contrast to other prognostic factors, impairment of IL-2 secretion may help to understand immunosuppression in SCLC and, thus, important elements of the pathogenesis of this disease.

Summary In order to evaluate the possible role of the proteolytic enzyme cathepsin B (cath B) in human non-small cell lung cancer (NSCLC) we examined cath B concentrations (cath B c ) and activities (cath B A ) in homogenates of 127 pairs of lung tumour tissues and corresponding nontumourous lung parenchyma. Total cath B activity (cath B AT ) and enzymatic activity of the fraction of cath B, which is stable and active at pH 7.5 (cath B A7.5 ) were determined by a fluorogenic assay using synthetic substrate Z-Arg-Arg-AMC. The immunostaining pattern of cath B was determined in 239 lung tumour tissue sections, showing the presence of the enzyme in tumour cells (cath B T-I ) and in tumour-associated histiocytes (cath B H-I ). The median levels of cath B AT , cath B A7.5 and cath B C were 5.6-, 3.2-and 9.1-fold higher (P < 0.001), respectively, in tumour tissue than in non-tumourous lung parenchyma. Out of 131 tissue sections from patients with squamous cell carcinoma (SCC), 59.5% immunostained positively for cath B, while among the 108 adenocarcinoma (AC) patients 48.2% of tumours showed a positive reaction. There was a strong relationship between the levels of cath B AT , cath B A7.5 , cath B C and cath B T-I in the primary tumours and the presence of lymph node metastases. Significant correlation with overall survival was observed for cath B T-I and cath B A7.5 (P < 0.01 and P < 0.05, respectively) in patients suffering from SCC. In these patients positive cath B in tumour cells (cath B T-I ) and negative cath B in histiocytes (cath B H-I ) indicated significantly shorter survival rate compared with patients with negative cath B T-I and positive cath B H-I (P < 0.0001). In contrast, in AC patients, both, positive cath B T-I and positive cath B H-I , indicated poor survival probability (P < 0.014). From these results we conclude that the proteolytic enzyme cath B is an independent prognostic factor for overall survival of patients suffering from SCC of the lung.

Residual tumor (R1) was proven at the proximal bronchial resection margin in 88 (3.6%) of 2464 cases of lung cancer following lung resection and standard lymph node dissection. Postoperative complications (8%) were: fistula of the bronchial suture line (n = 7), bleeding (n = 2) and heart luxation (n = 1). The in-hospital mortality was 16.6%. Causes of death were: bronchial fistula (n = 7), erosion of the pulmonary artery (n = 4), respiratory failure (n = 1), and empyema (n = 1). Forty-three patients received postoperative radiation therapy. Median survival of all patients following incomplete resection was 16 months, compared to 37 months following complete resection (P < 0.001). Length of survival was independent of tumor stage, histology, site of infiltration and postoperative radiation. In conclusion, in resection for lung cancer clear margins should be verified by intraoperative frozen section. In the case of residual tumor at the bronchial resection margin, wider resection is mandatory in stage I and II if the patient meets the functional criteria. Even in stage III a and III b prognosis is significantly better after complete resection than R1-resection; the difference, however, is smaller than in lower stages.

We retrospectively analysed 301 patients with diffuse malignant pleural mesothelioma (235 male, 66 female; median age 59 years). Prognosis depended significantly on patient age, evidence of pain, loss of weight, tumour cell type, stage, local and distant metastasis, involvement of peritoneum and surgical treatment. The overall median survival rate was 238 days, after extended pleuropneumonectomy 284 days, and after decortication 315 days - significantly better than the prognosis in patients without surgical treatment or exploratory thoracotomy. Pleuropneumonectomy should only be considered in young patients with an epithelial cell-type tumour (possibly with adjuvant chemotherapy). Decortication seems nowadays to be the treatment of choice.