|
|
||||||||
Ann Thorac Surg 1996;61:546-550
© 1996 The Society of Thoracic Surgeons
Divisions of Thoracic Surgery and Neurosurgery, Tochigi Cancer Center, Utsunomiya, Japan
Accepted for publication October 28, 1995.
| Abstract |
|---|
|
|
|---|
Methods. To assess the usefulness of follow-up using computed tomography of the brain for early detection and effective treatment of brain metastases, we prospectively studied 128 patients with completely resected nonsmall cell lung cancer. Follow-up computed tomographic scans were obtained every 2 to 6 months over 24 postoperative months in 69 patients and every 2 months for 6 postoperative months in 59.
Results. Brain metastases were discovered in 11 patients (8.6%), and 7 patients were neurologically asymptomatic when the metastases were diagnosed. Single metastasis was found in 5 patients and multiple metastases in 6. The maximal size of all but one lesion was less than 25 mm. The median survival time and 5-year survival rate in all 11 patients with brain metastases were 10 months and 24%, respectively. Furthermore, those in 7 asymptomatic patients were 25 months and 38%, respectively.
Conclusions. We consider intensive follow-up with computed tomography to be worthwhile for early detection and effective treatment of brain metastases in patients with completely resected lung cancer.
| Introduction |
|---|
|
|
|---|
After curative resection for nonsmall cell lung cancer, about one third to two thirds of patients have recurrent disease depending on the stage [15]. Brain metastases are a common mode of initial recurrence, and most cases are detected within the first 2 years after operation [6].
Although single metastasis is occasionally treated with surgical resection and a good result is obtained [711], brain metastases are usually associated with an ominous outcome even after whole-brain irradiation [12]. However, these intracranial tumors are not usually diagnosed until patients become neurologically symptomatic, and little effort for early detection of the metastases has been performed.
Computed tomography (CT) of the brain has a well-documented accuracy in detecting metastatic tumors [13] and has been also reported to be of value in the preoperative staging of patients with locally advanced nonsmall cell lung cancer who were free of neurologic symptoms [14, 15].
To assess whether intensive follow-up with CT would result in an earlier diagnosis of brain metastases and thus lead to earlier and more effective treatment, we prospectively studied 128 patients who underwent complete resection of primary lung cancer.
| Patients and Methods |
|---|
|
|
|---|
|
The patients were also scheduled for follow-up examinations other than brain CT 1 month after operation, then every 1 to 3 months for 2 years, and every 6 months thereafter. Especially for the population at high risk of recurrence, checkups during the first 2 years were performed using combinations of periodic bronchoscopy, chest CT, abdominal CT or ultrasonography, and bone scintigraphy [17]. When brain metastases were discovered on CT, extracranial metastatic lesions were surveyed. Metastatic tumors of the brain were usually treated by surgical resection and radiotherapy for single lesions and radiotherapy alone for multiple lesions. Survival was measured from the date treatment of brain metastases was initiated in each patient.
| Results |
|---|
|
|
|---|
|
|
Brain metastases were revealed within 12 months after operation in all but 1 patient with liver metastasis. Patient 2 was suspected to have metastasis on CT at the sixth month, and patient 5, who was not examined at the sixth month, showed symptomatic metastases at the eighth month. Therefore, 9 of the patients were considered to have brain metastases by the sixth postoperative month.
Of 7 asymptomatic patients, 4 had a single metastasis (Fig 1
) and the other 3 had two or three metastatic lesions (Fig 2
). Three of the 4 symptomatic patients had more than three metastatic tumors. The maximal diameters of brain metastases were less than 25 mm in all but 1 patient.
|
|
Three asymptomatic patients who had complete responses after treatment of brain metastasis survived more than 2 years. Furthermore, the 2 with a single metastasis each have remained well without recurrence, whereas the remaining 1 with multiple lesions had no further brain metastases before death. However, although the other 2 patients with asymptomatic tumors (patients 8 and 9) achieved good responses, they died of pneumonia during the treatment of brain metastases. The median survival time of all 11 patients was 10 months, and the 5-year survival rate was 24% calculated by the Kaplan-Meier method, whereas in the 7 asymptomatic patients, those were 25 months and 38%, respectively.
| Comment |
|---|
|
|
|---|
Computed tomography has become the radiologic procedure of choice for the diagnosis of brain metastases. It has been reported that CT is valuable for preoperative staging of neurologically intact patients with locally advanced or nonsquamous cell lung carcinoma because these patients have a high risk of metastases [14, 15]. From the results of follow-up studies [36], all patients undergoing curative operations were also considered a high-risk population for brain metastases. Demange and associates [9] reported, in a study of single brain metastasis from nonsmall cell lung cancer, that survival was better for patients in good neurologic condition at the time metastasis was discovered and thus emphasized early diagnosis. Therefore, we performed this prospective study of intensive follow-up with CT for early detection of recurrence.
In our study brain metastases developed in 8.6% of patients with completely resected lung cancer; this recurrence rate was comparable with those of previous reports [36]. However, although metastases in previous reports were usually detected after neurologic symptoms developed, we found 63.6% of patients with brain metastases in the asymptomatic state on follow-up using CT. Moreover, the number of metastases in all asymptomatic patients was small and the maximal sizes of almost all lesions were less than 25 mm. The median survival time and 5-year survival rate of all 11 of our patients with brain metastases were comparable with those of reported results in surgically resected single brain metastasis [711]. Furthermore, those of 7 asymptomatic patients, despite the inclusion of patients with multiple lesions, were excellent. We believe that treatment results were improved not only by earlier detection of the metastases but also by improvement of the cure rate because 2 patients (patients 1 and 2) have survived without recurrence 67 and 42 months after treatment, respectively, and seem to be cured. Otherwise multiple metastases in patient 3 were well controlled until death and his quality of life was well maintained for a longer period.
From our results, intensive follow-up with CT in patients with resected lung cancer is thought to facilitate earlier diagnosis of brain metastases and thus lead to the earlier and more effective treatment. However, there were some problems associated with the follow-up. One of the problems is that some asymptomatic patients had surgically inaccessible or multiple metastases. Moreover, notwithstanding this intensive follow-up, some patients were discovered to have recurrences after neurologic symptoms developed. Bindal and colleagues [18] recently reported that surgical treatment of multiple brain metastases in selected patients resulted in a significantly increased survival time and gave a prognosis similar to that of patients undergoing operation for single metastasis. Stereotactic radiosurgery has also been advocated as an effective treatment for surgically inaccessible or multiple lesions [19]. Therefore, some unresectable brain metastases detected in this study were considered suitable for these new therapeutic modalities because of the small number and sizes, especially in asymptomatic patients. Magnetic resonance imaging has recently become available for diagnosing brain tumors [20], and contrast-enhanced magnetic resonance imaging has been demonstrated as very sensitive for small lesions [21]. Follow-up with magnetic resonance imaging may be able to detect brain metastases in asymptomatic patients more frequently.
The second problem is the duration and interval of follow-up with CT. The schedule was initially set up for the first 2 years after operation because most brain metastases are found within that period [6]. Eight patients in the early series were discovered to have brain metastases within the first 12 months, and in 7, except for patient 10, the metastases were considered to have developed by the sixth month. Consequently, in the late series, follow-up was performed more frequently during the first 6 months after operation. If the latter program had been applied to the entire study population, the same result except for patient 10 would have been obtained. Accordingly, follow-up CT every 2 months for the first 6 months after operation is considered sufficient for early detection.
The cost of follow-up is the most controversial issue. This should be assessed not only in terms of the cost of examinations itself but also in terms of the improvement in quality of life, survival time, and cure rate in patients with brain metastases. From this perspective, a randomized trial comparing follow-up with and without CT is needed to assess the cost benefit. Furthermore, it is necessary that the population for such follow-up be selected based on the risk of brain recurrence. In our study no brain recurrence was found in patients with stage I or II squamous cell carcinoma. The Lung Cancer Study Group reported that patients with T1 N0 squamous cell carcinoma had a very low risk of metastases [1, 6]. However, they also documented that patients with T1 N0 nonsquamous carcinoma and T2 N0 or stage II squamous cell carcinoma had a higher probability of recurrence in the brain [1, 6]. Therefore, we recommend this follow-up using brain CT for all patients with resected lung cancer except for those with T1 N0 squamous cell carcinoma.
In conclusion, we consider that intensive follow-up with CT facilitates early detection and effective treatment of brain metastases in patients with completely resected lung cancer. Nevertheless, the ultimate value of this follow-up study can only be determined by controlled, randomized trials.
| Acknowledgments |
|---|
|
|
|---|
| Footnotes |
|---|
|
|
|---|
| References |
|---|
|
|
|---|
Related Article
This article has been cited by other articles:
![]() |
K. E. Posther, L. M. McCall, D. H. Harpole Jr., C. E. Reed, J. B. Putnam Jr., V. W. Rusch, and B. A. Siegel Yield of Brain 18F-FDG PET in Evaluating Patients with Potentially Operable Non-Small Cell Lung Cancer J. Nucl. Med., October 1, 2006; 47(10): 1607 - 1611. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. M. Marom, H. P. McAdams, J. J. Erasmus, P. C. Goodman, D. K. Culhane, R. E. Coleman, J. E. Herndon, and E. F. Patz Jr Staging Non-Small Cell Lung Cancer with Whole-Body PET Radiology, September 1, 1999; 212(3): 803 - 809. [Abstract] [Full Text] |
||||
![]() |
F. E. IV, J. H. Ryu, G. M. Miller, P. H. Luetmer, L. A. Forstrom, O. L. Burnett, C. M. Rowland, S. J. Swensen, and D. E. Midthun Suspected Non–Small Cell Lung Cancer: Incidence of Occult Brain and Skeletal Metastases and Effectiveness of Imaging for Detection—Pilot Study Radiology, April 1, 1999; 211(1): 137 - 145. [Abstract] [Full Text] |
||||
![]() |
C. A.B. Saunders, J. E. Dussek, M. J. O'Doherty, and M. N. Maisey Evaluation of fluorine-18-fluorodeoxyglucose whole body positron emission tomography imaging in the staging of lung cancer Ann. Thorac. Surg., March 1, 1999; 67(3): 790 - 797. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Yokoi, N. Kamiya, H. Matsuguma, S. Machida, T. Hirose, K. Mori, and K. Tominaga Detection of Brain Metastasis in Potentially Operable Non-small Cell Lung Cancer: A Comparison of CT and MRI Chest, March 1, 1999; 115(3): 714 - 719. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |