Kinetic analysis of recurrence and survival after potentially curative resection of nonsmall cell lung cancer

BACKGROUND

About two-thirds of the patients with nonsmall cell lung cancer (NSCLC) who undergo a potentially curative resection eventually suffer from recurrent disease. However, it has yet to be elucidated as to how survival after recurrence is influenced by different variables, including timing, type of recurrence, or other clinicopathological features. There have been few studies concentrating on the kinetics of growth of occult micrometastatic tumor cells that eventually manifest as tumor recurrence.

METHODS

We retrospectively reviewed the charts of 197 patients who developed recurrence after a potentially curative resection for NSCLC.

RESULTS

The median disease-free interval was a little over 1 year (395 days), as was the median postrecurrence survival-383 days. We created a model for the kinetics of recurrence by assuming that: (1) a tumor of 10(9) cells is the usual limit of detection, (2) patients generally die before the tumor reaches 10(12) cells, and (3) it takes 1 year for average lung cancer cells to show a 10-fold increase. The model indicated that as much as 10(9) tumor cells should have been present immediately after the operation. Alternatively, the residual tumor cells should have an accelerated growth after the surgery.

CONCLUSIONS

These models indicate the importance of developing a sensitive detection method for occult metastatic cells and to understand the tumor dormancy mechanism.

Video-assisted thoracoscopic surgery of bullous and bleb disorders of the lung using endoscopic stapling device

The video-assisted thoracic surgical (VATS) approach appears to be a viable alternative to thoracotomy when surgical management of bullous and bleb disorders of the lung is required. Fifty patients with giant bullae (n = 6) and spontaneous pneumothoraces (n = 44) were recently treated by our group using the VATS approach and endoscopic stapling devices. Of the 50 patients, 47 were managed completely by the VATS approach, including six giant bullae that were asymptomatic in five and infectious in one and 41 pneumothoraces, of which 16 were first episode and 25 with recurrent pneumothorax. Median operating times for the bullous and bleb excisions were 147.8 and 45.9 min, respectively (p < 0.01), and median chest tube durations were 5.2 and 1.2 days, respectively (p < 0.05). There was no mortality, and significant morbidity was limited to prolonged air leak in more than 5 days in three patients and postoperative atelectasis in two patients. Median hospital stays of patients with bullous excision was 11.3 days compared with 4.7 days of those with bleb excision. We conclude that the VATS treatment is a safe, effective procedure in patients with bullous and bleb disorders of the lung even in asymptomatic giant bullae or spontaneous pneumothoraces with the first episode. The advantages of the VATS approach for these diseases are ease of operation, less pain, early mobility, and superior cosmetic results.

Different site mutation of the K-ras gene in a patient with metachronous double lung cancers

We present a case with metachronous double lung cancers proved by molecular analysis. A male patient first had lung cancer discovered when he was 67 years old, and a second lung cancer was found when he was 71 years old. Pathologically, the first cancer was moderately to well differentiated adenocarcinoma and the second cancer was well differentiated adenocarcinoma. These findings suggested that the second cancer was not metastasis from the first lung cancer but a second primary lung cancer. According to the PCR and oligonucleotide mutation specific dot blot hybridization, the first lung cancer had a GGT to GTT mutation, while the second lung cancer had a GGT to TGT mutation at codon 12 of the K-ras gene. These results thus prove that these tumors were metachronous double cancers.

Antitumor activity of regional lymph node lymphocytes in patients with lung cancer

Cytotoxic activities of regional lymph node lymphocytes (RLNL) and peripheral blood lymphocytes (PBL) of 49 primary lung cancer patients who were subjected to surgical resection were examined by 4 h 51Cr release assay. PBL showed significantly lower cytotoxicity against autologous tumor cells than against K562 and QG-56. On the other hand, RLNL exhibited the same level of cytotoxicity against autologous tumor cells as PBL, although the cytotoxicities against K562 and QG-56 were low. Cytotoxicity of RLNL against autologous tumor cells exhibited a significant degree of depression with the advance of stage, T and N factors. Cytotoxicity of PBL did not significantly change as the stage progressed. When both PBL and RLNL were cultured with purified interleukin-2 (p-IL2) in vitro, their cytotoxic activities were markedly augmented and the cytotoxicities could not be diminished by the treatment with anti-Leu-7 + anti-Leu-11b + C'. These facts indicate that the augmented cytotoxicity may be due to lymphokine activated killer (LAK) cells.

Randomly controlled study of chemotherapy versus chemoimmunotherapy in postoperative lung cancer patients

A randomly controlled study of chemotherapy versus chemoimmunotherapy was performed in patients with operable lung cancer from November 1977 to June 1981. The immunotherapy consisted of an intrapleural instillation of Nocardia rubra cell wall skeleton (N-CWS) followed by serial intradermal N-CWS. A total of 119 patients were entered into this trial. There were 64 evaluable patients in the control group and 52 evaluable patients in the N-CWS group. N-CWS treatment was effective in terms of prolongation of duration of remission for all operable patients. Although significant improvement in the survival rate was not observed in patients at Stages I and II (p less than 0.10), it was observed in the curative operation group (p less than 0.05). The mode of recurrence was classified as local recurrence and distant metastasis in the curative operation group. The rates of distant metastasis were 34.0 and 18.9%, respectively, in the control and the N-CWS groups. The rate of local recurrence was 14.9% in the control group; however, no local recurrence was observed in the N-CWS group. These results indicate the clinical effectiveness of the N-CWS treatment, especially in curatively resectable lung cancer. No serious side effect was observed during this trial.

Antitumor activity of macrophages in lung cancer patients with special reference to location of macrophages

Antitumor activity of macrophages from the peripheral blood, pleural cavity, and alveoli of 35 patients with primary lung cancer was examined. Cytostatic activities of peripheral blood monocytes and alveolar macrophages from either tumor-bearing or non-tumor-bearing segments declined in association with metastasis to regional lymph nodes, an increase in tumor size, and the development of pleural invasion. However, no such correlation could be observed between the cytostatic activity of pleural cavity macrophages and the degree of pleural invasion. The cytostatic activity of pleural cavity macrophages was found to be suppressed when the pleural invasion extended beyond the visceral pleura to the neighboring lobe or chest wall. On the other hand, the cytostatic activity of pleural cavity macrophages was markedly augmented when pleural invasion was limited to within the visceral pleura, although it was low in patients with no visceral pleural invasion. These results suggest that the pleural cavity is isolated from sites of systemic immunological response and that systemic immunological response does not strongly affect pleural cavity macrophages.

[Effect of adjuvant immunotherapy with Nocardia rubra cell-wall skeleton in lung cancer]

A randomized clinical trial of intrapleural Nocardia rubra cell-wall skeleton (N-CWS) followed by intradermal N-CWS was performed against lung cancer patients from November, 1977 to June 1981. Totally, 190 patients were entered into this trial. The N-CWS treatment was effective in terms of prolongation of remission duration against not only operable but also inoperable patients. However, significant improvement of survival rate was observed only in operable patients, especially curative+relatively curative resection-group (p less than 0.05). The mode of recurrence was classified as local recurrence and distant metastasis in the curative+relatively curative resection-group. The rates of distant metastasis were 34.1 and 17.6%, respectively, in the control and the N-CWS groups. The rate of local recurrence was 13.6% in the control group, however, no local recurrence was observed in the C-NWS group. These results indicate the clinical effectiveness of the N-CWS treatment especially in curatively resectable lung cancer. No serious side effect was experienced during this trial.

Combined treatment of autochthonous 3-methylcholanthrene-induced murine tumors by immunotherapy and radiotherapy

C57BL/6J mice with autochthonous 3-methylcholanthrene-induced tumors were given combined therapy with 2,000 rad of local irradiation and regional injections of cell-wall skeleton of Nocardia rubra (N-CWS). The greatest suppression of the tumor growth and the highest survival rate were observed in the combined treatment group as compared to the non-treated control, regional injections of N-CWS alone and irradiation alone groups. In addition, pulmonary metastasis was significantly suppressed by the combined therapy.

Successful regional immunotherapy with cell-wall skeletons of BCG and Nocardia rubra against autochthonous rat tumors

Autochthonous tumors induced by 3-methylcholanthrene (MCA) in the thigh of Fischer 344 rats were treated by nonspecific immunotherapy with cell-wall skeleton of BCG (BCG-CWS) or Nocardia rubra (N-CWS) after incomplete radiotherapy. When MCA-induced autochthonous tumors grew to 3 cm in diameter, they were resected and autografted to the contralateral thigh. When the autografted tumors reached 1 cm in diameter, they were exposed to a single irradiation with 2000 rad giving rise to complete shrinkage in 16.6% of the cases. The rates of complete shrinkage were increased to 36.4% and 58.3%, respectively, by combined regional immunotherapy with BCG-CWS or N-CWS. Furthermore, immunoprophylactic effects of BCG-CWS and N-CWS were also detected in this experimental system.