HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Saito, Y. Search for Related Content PubMed Articles by Saito, Y. Related Collections Lung - other Related Article

Ann Thorac Surg 2005;79:283
© 2005 The Society of Thoracic Surgeons

INVITED COMMENTARY

Department of Thoracic and Cardiovascular Surgery, Kansai Medical University, 10-15 Fumizonocho, Moriguchi 570-8507, Japan

Pulmonary metastasectomy has become a widely accepted surgical treatment for a patient with metastatic lung tumor. In the study by Shiono and colleagues, the overall 5-year survival rate of the patients who underwent pulmonary metastasectomy seems to be extremely high compared with the survival rates reported by several authors previously. After 5 years, however, the survival curve in this study decreased, to less than 40% at 84 months. Presumably, an excellent 5-year survival rate would be a reflection of a length bias caused by the biological behavior of the metastatic pulmonary lesions.

In this paper, Shiono and associates did not identify any clinical factors, including preoperative serum carcinoembryonic antigen (CEA) levels, that were significantly related to prognosis. Previous reports in the literature have indicated, however, that preoperative serum CEA levels do appear to be significant predictors of survival after resection of pulmonary metastases. We have also reported, in the Journal of Thoracic and Cardiovascular Surgery, that the status of the hilar or mediastinal lymph nodes and the prethoracotomy serum CEA levels were significant independent prognostic factors. We believe these findings are useful in the follow-up of patients who have undergone pulmonary metastasectomy of colorectal cancer. Prethoracotomy serum CEA levels are also a prognostic indicator in metastatic colorectal cancer when the cutoff level is defined as 10.0 ng/mL. Shiono and colleagues could have found serum CEA level to be a significant prognostic factor if the cutoff level had been defined as 10.0 ng/mL.

This paper sheds further light on predicting survival among patients who have undergone pulmonary metastasectomy. The Shiono study concluded that the morphologic features of aerogenous spreading and vascular invasion at metastatic sites are significant prognostic factors for colorectal cancer patients who have undergone pulmonary metastasectomy. Unfortunately, the authors did not clarify the mechanisms of aerogenous spreading and vascular invasion that would provide insight into the aggressive behavior of metastatic colon cancer. From a similar viewpoint, not involving metastatic lung tumor, Jin and associates described the aerogenous spread of primary lung adenocarcinoma induced by remodeling alveolar capillary endothelium. Their previous studies had identified endothelial fenestration in alveolar capillaries. These capillaries were always in close apposition to alveolar epithelial cells that were proliferating or regenerating; the localization of fenestra-bearing endothelial cells suggested new growth and consequential phenotypic changes of the endothelial cells. Both topical and chronic exposure to vascular endothelial growth factor 165 (VEGF165) could induce fenestrae formation in vascular endothelial cells in the microvascular bed. Vascular endothelial growth factor 120 and VEGF164 have been identified as the predominant forms in lung cancer and appear to be required for inducing fenestrae formation in endothelial cells. Fenestrae were confined to the alveolar capillaries and the microvessels of intraalveolar structures that were similarly associated with neoplastic cell invasion. Jin and colleagues concluded that these histochemical and ultrastructual changes appeared to be closely related to higher expression of diffusible forms of VEGF mRNA released from neoplastic cells.

We hope Shiono and colleagues will be able to identify molecular markers for aerogenous spreading and vascular invasion in the near future. Finally, these investigators are to be congratulated for shedding further light on prognosis prediction and for identifying prognostic factors histopathologically related to resected colorectal lung metastases.

Related Article

Histopathologic Prognostic Factors in Resected Colorectal Lung Metastases

Satoshi Shiono, Genichiro Ishii, Kanji Nagai, Junji Yoshida, Mitsuyo Nishimura, Yukinori Murata, Koji Tsuta, Yutaka Nishiwaki, Tetsuro Kodama, and Atsushi Ochiai
Ann. Thorac. Surg. 2005 79: 278-282. [Abstract] [Full Text] [PDF]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Saito, Y. Search for Related Content PubMed Articles by Saito, Y. Related Collections Lung - other Related Article