Diagnosis of solitary pulmonary nodule: optimal strategy based on nodal size
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《血管的通路杂志》
a Department of Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-City, Osaka 565-0871, Japan
b Division of Surgery for Chest Disease, Toneyama National Hospital, Osaka, Japan
c Division of Medicine, Toneyama National Hospital, Osaka, Japan
This paper was presented at the 21st Meeting of the Japanese Association for Chest Surgery, on May 28, 2004.
Abstract
We attempted to determine the smallest size of nodule that could be accurately diagnosed by fluoroscopic fiberoptic bronchoscopy (FFB) and computed tomography (CT) guided trans-corporeal biopsy (CTGB) procedures. Parenchymal lesions (n=1483) detected using chest roentgenography were investigated in the present study, and the diagnostic capabilities of FFB and CTGB were determined based on receiver-operating characteristic curves. A total of 990 nodules (67%) were diagnosed using FFB, while 58 (4%) were diagnosed with CTGB, 339 (23%) by surgery, and 100 (6%) by other methods. The area under the curve (AUC) was 0.74 (0.72<95% CI <0.77) in FFB cases and 0.95 (0.92<95% CI <0.98) in CTGB cases. FFB was found capable of diagnosing nodules with sizes between 0 and 1.0 cm, 1.0 and 1.5 cm, 1.5 and 2.0 cm, and more than 2.0 cm at ratios of 0/58 (0%), 19/115 (16%), 59/141 (35%), and 1072/1173 (97%), respectively (P<0.0001). The diagnostic ability of CTGB for nodules categorized in the same manner was 0/25 (0%), 2/29 (7%), 5/24 (21%), and 53/63 (84%), respectively (P<0.0001). For SPNs smaller than 1.5 cm in diameter, both FFB and CTGB showed a low diagnostic sensitivity.
Key Words: Solitary pulmonary nodule; Tumor size; Fiberoptic bronchoscope; Excision
1. Introduction
A solitary pulmonary nodule (SPN) is most definitively diagnosed using surgery, namely nodule excision via a thoracotomy or video-assisted thoracic surgery (VATS) [1]. However, the most commonly utilized option to diagnose such a pulmonary nodule is fluoroscopic fiberoptic bronchoscopy (FFB) [2], while computed tomography (CT) guided trans-corporeal biopsy (CTGB) is also indicated for SPN diagnosis [3]. In addition, ultrathin bronchoscopy [4] is a new technique under investigation that may be useful, while sputum, pleural effusion, and palpable lymph nodes have also been reported as specimens useful for diagnosis.
Although a bronchoscopy procedure is generally believed to be appropriate if the lesion is 2.0 cm or larger in size, there have been few investigations of the breakpoint between sizes for reliable results using a statistical method. Non-surgical techniques can be performed under local anesthesia with less intervention than a surgical technique, which must be carried out using general anesthesia, and should be used prior to surgery, though those with a very low sensitivity should be avoided. We conducted a retrospective study to estimate the size at which an SPN could be diagnosed without using a surgical method in an attempt to elucidate optimal diagnostic techniques.
2. Patients and methods
From 1988 to 2003, 1487 patients, 926 males and 561 females, with ages ranging from 19 to 83 years old (median, 63 years), with parenchymal lesions that could be identified by chest roentgenography were investigated. For an SPN, we routinely carry out both CT and FFB examinations at Toneyama National Hospital. During FFB, the lesions were diagnosed using a curette cytology technique followed by a lavage cytology technique. In addition, a biopsy was carried out in 18 cases with visible lesions. The overall complication rate was 2% (30/1487), including 16 (1.1%) incidents of hemorrhage and 3 (0.2%) of pneumothorax without death. Recently, the number of cases of pure ground-grass-opacity (GGO) undetectable on chest X-ray images is growing. We had 28 cases of pure GGO, however, because of the differences in clinical features between lesions detectable and undetectable by roentgenography, the present investigation did not include such lesions.
2.1. Prevalent of nodule characteristics
The prevalent nodule characteristics are shown in Table 1. Nodule sizes ranged from 0.4 to 16 cm, with a median of 4.1 cm. Histological diagnoses of nodules were lung cancer in 1212 cases (small cell carcinoma in 218 and non-small cell lung cancer in 994), metastasis in 17 cases (colon cancer in 16 and breast cancer in 1), and benign lesions in 248 cases. The clinical stages of IA, IB, IIA, IIB, IIIA, IIIB and IV were seen in 322, 435, 10, 12, 138, 99 and 196 patients, respectively.
2.2. Data analysis and statistical considerations
Statistical analysis was performed using the SPSS package for Windows, version 9.0 (SPSS, Chicago, IL), with medians and ranges used to describe continuous variables. To assess the capabilities of FFB and CTGB for diagnosis, we used receiver-operating characteristic (ROC) curves, whose circumscribed areas (under the curve) provided an estimate of the probability efficiency in the present study, in other words the probability efficiency of successful diagnosis using FFB or CTGB. ROC curves were also used for nodule size. The ratios of successful diagnoses with FFB and CTGB were calculated by nodule size with breakpoints set at 1.0 cm, 1.5 cm, 2.0 cm, 2.5 cm, 3.0 cm, 4.0 cm, and 5.0 cm, and then examined using a 2 test. A probability (P) level less than 0.05 was considered to be statistically significant.
3. Results
A flow-chart of patient diagnoses is shown in Fig. 1. There were 1487 patients who had lesions diagnosed using a non-surgical technique and 339 whose lesions were diagnosed using surgery. Of the 1148 non-surgical cases, 990 nodules were diagnosed using FFB, 58 by CTGB, and 100 by other methods (sputum cytology in 36 cases, fine needle aspiration cytology of palpable lymph nodes in 30 cases, cytology of minor pleural effusion detected by chest computed tomography in 24 cases, cytology of pericardial effusion in 8 cases, and mediastinal lymph node test using mediastinoscopy in 2 cases). Of the 339 surgical cases, a thoracotomy was used in 10 (3%) and VATS in 329 (97%). In the group of patients who underwent VATS, 3 (1%) received a conversion thoracotomy. Eighty-two nodules could not be diagnosed by CTGB and 257 were surgically diagnosed without the use of CTGB. The extension of lung resection was excision in 329 cases, segmentectomy in 7 cases, and lobectomy in 3 cases. There were no mortalities in the surgical cases, while a single (0.3%) case had an operative complication, postoperative bleeding that required a re-thoracotomy. We performed CTGB only after receiving informed consent, as an air embolism is a severe complication that can lead to death [5] and implantation of malignant cells can lead to recurrence [6]. The CTGB procedures were carried out using a 22-gauge needle and showed a post-operative complication rate of 14% (20/140), including 19 (13%) cases of pneumothorax and 1 (0.7%) of hemoptysis.
FFB was able to diagnose 67% (990/1487) of all nodules and the area under the ROC curve was 0.74 (0.72<95% CI <0.77) (Fig. 2). The ratios of successful diagnosis using FFB for tumors sized between 0 cm and 1.0 cm, 1.0 and 1.5 cm, 1.5 and 2.0 cm, and greater than 2.0 cm were 0% (0/58), 16% (19/115), 35% (59/141), and 97% (1072/1173), respectively (P<0.0001) (Fig. 3). Based on our results, we concluded that there was little difference in the possibility of diagnosis among the various tumor locations. Tumor location was the right upper lobe in 544 cases, right middle lobe in 92 cases, right lower lobe in 269 cases, left upper lobe in 399 cases, left lower lobe in 147 cases, and unknown in 56 cases. Further, the number of lesions diagnosed using FFB in the right upper lobe was 351 (65%), while it was 69 (64%) in the right middle lobe, 175 (65%) in the right lower lobe, 280 (70%) in the left upper lobe, and 105 (71%) in the left lower lobe. In addition, diagnosis was possible for 45/248 (18%) benign lesions and 945/1212 (83%) malignant lesions. CTGB was carried out in 9% (139/1147) of the cases and the area under the ROC curve was 0.95 (0.92<95% CI <0.98) (Fig. 4). Ratios of successful diagnosis by CTGB using the same size categories as for FFB were 0% (0/25), 7% (2/29), 21% (5/24), and 84% (53/63), respectively (P<0.0001) (Fig. 5).
The area under the curve is 0.95 (0.92<95% CI <0.98). CI: confidence interval.
4. Discussion
An FFB is a relatively low risk procedure with an overall complication rate of 5%, including a mortality rate of 0.24%, though its diagnostic success for an SPN is dependent on tumor size [7]. Swenson et al. [8] found that the success rate for malignant lesions less than 1.5 cm in diameter was 10%, while it rose to between 40% and 60% for those between 2 and 3 cm in diameter. Thus, that method is considered to have limited utility and few benefits for patients with a pulmonary nodule less than 1.5 cm in diameter. That was confirmed in our study, as the ratio for successful diagnosis using FFB for tumors sized between 0 and 1.0 cm and those from 1.0 to 1.5 cm was 0% (0/58) and 16% (19/115), respectively. Therefore, FFB is not recommended for patients with an SPN smaller than 1.5 cm in diameter.
Ultra-thin bronchoscopy is generally utilized for direct visualization of more peripheral lesions in small airways, as it allows visualization of airways to the ninth generation [4]. This technique has been used experimentally, however, whether it provides a clinically significant increase in sensitivity remains unclear.
CTGB is another technique that should be considered for patients with an SPN, as it has a reported diagnostic success ratio of up to 95% for peripheral pulmonary lesions [9], though previous investigations have shown false-negative rates ranging from 3% to 29%. In addition, for a small-sized SPN less than 2 cm in diameter, CTGB was reported to have a success rate of approximately 60% [10]. However, those studies noted complication rates higher than those for a bronchoscopy, such as an up to 30% incidence of pneumothorax, though many of the patients did not require chest tube drainage. In addition, an air embolism, though rare, is a severe complication that can cause death [5], while another potential complication is implantation of malignant cells that can lead to recurrence [6], which may be due to those cells being spread through the needle tract [10]. As a result, we only perform CTGB after receiving informed consent from the patient.
A lesion that cannot be diagnosed as benign using FFB, CTGB, or both requires careful radiographic follow-up, as well as additional diagnostic tests such as a positron emission tomography (PET) scan or thoracotomy, because of possible false-negative results.
A PET scan has been used in many investigations for differentiation between benign and malignant SPNs [11], and its sensitivity and specificity for those has been shown to range from 89 to 100% and 79 to 100%, respectively, with diagnostic accuracy reported to range from 89 to 100%. However, false-negative results can occur in association with bronchiolo-alveolar carcinomas, carcinoids, and tumors less than 1 cm in diameter [12,13]. Therefore, surgery is strongly recommended for patients with a small-sized SPN less than 1 cm in diameter.
A thoracotomy is the most accurate technique for diagnosis of an SPN and when performed for patients with malignant pulmonary nodules, the technique has shown an operative mortality of 3 to 7% and resectability rates ranging from 80 to 100%, while resection of benign nodules has a reported mortality of less than 1% [14]. VATS offers the benefits of low rates of perioperative morbidity and mortality [1]. Further, both thoracotomy and VATS have specific advantages, as a residual lobectomy can be carried out if frozen section histology results lead to a diagnosis of malignancy during the operation. In addition, patients with non-small cell lung cancer diagnosed using a trans-pleural technique have a better long-time survival rate than those whose diagnosis was made with FFB [15].
Only a few studies have been performed regarding SPN breakpoint size for thoracotomy or VATS, though the results would be useful for practicing surgeons. The present findings revealed that the diagnostic success ratios without tumor excision in 1478 patients who had undergone an FFB technique for nodules sized between 0 and 1.0 cm, 1.0 and 1.5 cm, 1.5 and 2.0 cm, and greater than 2.0 cm were 0%, 14%, 37% and 91%, respectively.
Although our study has some limitations, these results from a large patient population should be helpful to provide further direction for investigation. In addition, the data will be useful for both physicians and surgeons. As a result of our findings, surgery for diagnosis of nodules using a thoracotomy or VATS may be recommended for operable patients with a small SPN sized less than 1.5 cm in diameter and optimal for patients with an SPN smaller than 1.0 cm in diameter. However, a prospective study would be helpful to elucidate the optimal strategy for patients with an SPN.
References
Landreneau RJ, Hazelrigg SR, Ferson PF, Johnson JA, Nawarawong W, Boley TM, Curtis JJ, Bowers CM, Herlan DB, Dowling RD. Thoracoscopic resection of 85 pulmonary lesions. Ann Thorac Surg 1992; 54:415–420.
Gasparini S, Ferretti M, Secchi EB, Baldelli S, Zuccatosta L, Gusella P. Integration of transbronchial and percutaneous approach in the diagnosis of peripheral pulmonary nodele or masses. Chest 1995; 108:131–137.
Schriber G, McCrory DC. Performance characteristics of different mordalities for diagnosis of suspected lung cancer. Chest 2003; 123:115s–128s.
Tanaka M, Takizawa H, Satho M, Okada Y, Yamasawa F, Umeda A. Assessment of an ultrathin bronchoscope that allows cytodiagnosis of small airways. Chest 1994; 106:1443–1447.
Aberle DR, Gamsu G, Golden JA. Fatal systemic arterial air embolism following lung needle aspiration. Radiology 1987; 165:351–353.
Kim JH, Kim YT, Lim HK, Kim YH, Sung SW. Management for chest wall implantation of non-small cell lung cancer after fine-needle aspiration biopsy. Eur J Cardiothorac Surg 2003; 23:828–832.
Wallance JM, Deutsch AL. Flexible fiberoptic bronchoscopy and percutaneus needle lung aspiration for evaluating the solitary pulmonary nodule. Chest 1982; 81:655–671.
Swensen SJ, Jett JR, Payne WS, Viggiano RW, Pairolero PC, Trastek VF. An integrated approach to evaluation of the solitary pulmonary nodule. Mayo Clin Proc 1990; 65:173–186.
Berquist TH, Bailey PB, Cortese DA, Miller WE. Transthoracic needle biopsy: accuracy and complications in relation to location and type of lesion. Mayo Clin Proc 1980; 55:475–481.
Sawabata N, Ohta M, Maeda H. Fine-needle aspiration cytologic technique for lung cancer has a high potential of malignant cell spread through the tract. Chest 2000; 118:936–939.
Dewan NA, Gupta NC, Redepenning LS, Phalen JJ, Frick MP. Diagnostic efficacy of PET-FDG imaging in solitary pulmonary nodules: potential role in evaluation and management. Chest 1993; 104:997–1002.
Higashi K, Ueda Y, Seki H, Yuasa K, Oguchi M, Noguchi T, Taniguchi M, Tonami H, Okimura T, Yamamoto I. Fluorine-18-FDG PET imaging is negative in bronchioloalveolar lung carcinoma. J Nucl Med 1998; 39:1016–1020.
Erasmus JJ, McAdams HP, Patz EF Jr, Coleman RE, Ahuja V, Goodman PC. Evaluation of primary pulmonary carcinoid tumors using FDG-PET. AJR 1998; 170:1369–1373.
Steele JD. The solitary pulmonary nodule: report of a cooperative study of resected asymptomatic solitary pulmonary nodules in males. J Thorac Cardiovasc Surg 1963; 46:21–39.
Sawabata N, Maeda H, Ohta M, Nakagawa M. Operable non-small cell lung cancer diagnosed by transpleural techniques: do they affect relapse and prognosis. Chest 2001; 120:1595–1598.(Noriyoshi Sawabata, Soich)
b Division of Surgery for Chest Disease, Toneyama National Hospital, Osaka, Japan
c Division of Medicine, Toneyama National Hospital, Osaka, Japan
This paper was presented at the 21st Meeting of the Japanese Association for Chest Surgery, on May 28, 2004.
Abstract
We attempted to determine the smallest size of nodule that could be accurately diagnosed by fluoroscopic fiberoptic bronchoscopy (FFB) and computed tomography (CT) guided trans-corporeal biopsy (CTGB) procedures. Parenchymal lesions (n=1483) detected using chest roentgenography were investigated in the present study, and the diagnostic capabilities of FFB and CTGB were determined based on receiver-operating characteristic curves. A total of 990 nodules (67%) were diagnosed using FFB, while 58 (4%) were diagnosed with CTGB, 339 (23%) by surgery, and 100 (6%) by other methods. The area under the curve (AUC) was 0.74 (0.72<95% CI <0.77) in FFB cases and 0.95 (0.92<95% CI <0.98) in CTGB cases. FFB was found capable of diagnosing nodules with sizes between 0 and 1.0 cm, 1.0 and 1.5 cm, 1.5 and 2.0 cm, and more than 2.0 cm at ratios of 0/58 (0%), 19/115 (16%), 59/141 (35%), and 1072/1173 (97%), respectively (P<0.0001). The diagnostic ability of CTGB for nodules categorized in the same manner was 0/25 (0%), 2/29 (7%), 5/24 (21%), and 53/63 (84%), respectively (P<0.0001). For SPNs smaller than 1.5 cm in diameter, both FFB and CTGB showed a low diagnostic sensitivity.
Key Words: Solitary pulmonary nodule; Tumor size; Fiberoptic bronchoscope; Excision
1. Introduction
A solitary pulmonary nodule (SPN) is most definitively diagnosed using surgery, namely nodule excision via a thoracotomy or video-assisted thoracic surgery (VATS) [1]. However, the most commonly utilized option to diagnose such a pulmonary nodule is fluoroscopic fiberoptic bronchoscopy (FFB) [2], while computed tomography (CT) guided trans-corporeal biopsy (CTGB) is also indicated for SPN diagnosis [3]. In addition, ultrathin bronchoscopy [4] is a new technique under investigation that may be useful, while sputum, pleural effusion, and palpable lymph nodes have also been reported as specimens useful for diagnosis.
Although a bronchoscopy procedure is generally believed to be appropriate if the lesion is 2.0 cm or larger in size, there have been few investigations of the breakpoint between sizes for reliable results using a statistical method. Non-surgical techniques can be performed under local anesthesia with less intervention than a surgical technique, which must be carried out using general anesthesia, and should be used prior to surgery, though those with a very low sensitivity should be avoided. We conducted a retrospective study to estimate the size at which an SPN could be diagnosed without using a surgical method in an attempt to elucidate optimal diagnostic techniques.
2. Patients and methods
From 1988 to 2003, 1487 patients, 926 males and 561 females, with ages ranging from 19 to 83 years old (median, 63 years), with parenchymal lesions that could be identified by chest roentgenography were investigated. For an SPN, we routinely carry out both CT and FFB examinations at Toneyama National Hospital. During FFB, the lesions were diagnosed using a curette cytology technique followed by a lavage cytology technique. In addition, a biopsy was carried out in 18 cases with visible lesions. The overall complication rate was 2% (30/1487), including 16 (1.1%) incidents of hemorrhage and 3 (0.2%) of pneumothorax without death. Recently, the number of cases of pure ground-grass-opacity (GGO) undetectable on chest X-ray images is growing. We had 28 cases of pure GGO, however, because of the differences in clinical features between lesions detectable and undetectable by roentgenography, the present investigation did not include such lesions.
2.1. Prevalent of nodule characteristics
The prevalent nodule characteristics are shown in Table 1. Nodule sizes ranged from 0.4 to 16 cm, with a median of 4.1 cm. Histological diagnoses of nodules were lung cancer in 1212 cases (small cell carcinoma in 218 and non-small cell lung cancer in 994), metastasis in 17 cases (colon cancer in 16 and breast cancer in 1), and benign lesions in 248 cases. The clinical stages of IA, IB, IIA, IIB, IIIA, IIIB and IV were seen in 322, 435, 10, 12, 138, 99 and 196 patients, respectively.
2.2. Data analysis and statistical considerations
Statistical analysis was performed using the SPSS package for Windows, version 9.0 (SPSS, Chicago, IL), with medians and ranges used to describe continuous variables. To assess the capabilities of FFB and CTGB for diagnosis, we used receiver-operating characteristic (ROC) curves, whose circumscribed areas (under the curve) provided an estimate of the probability efficiency in the present study, in other words the probability efficiency of successful diagnosis using FFB or CTGB. ROC curves were also used for nodule size. The ratios of successful diagnoses with FFB and CTGB were calculated by nodule size with breakpoints set at 1.0 cm, 1.5 cm, 2.0 cm, 2.5 cm, 3.0 cm, 4.0 cm, and 5.0 cm, and then examined using a 2 test. A probability (P) level less than 0.05 was considered to be statistically significant.
3. Results
A flow-chart of patient diagnoses is shown in Fig. 1. There were 1487 patients who had lesions diagnosed using a non-surgical technique and 339 whose lesions were diagnosed using surgery. Of the 1148 non-surgical cases, 990 nodules were diagnosed using FFB, 58 by CTGB, and 100 by other methods (sputum cytology in 36 cases, fine needle aspiration cytology of palpable lymph nodes in 30 cases, cytology of minor pleural effusion detected by chest computed tomography in 24 cases, cytology of pericardial effusion in 8 cases, and mediastinal lymph node test using mediastinoscopy in 2 cases). Of the 339 surgical cases, a thoracotomy was used in 10 (3%) and VATS in 329 (97%). In the group of patients who underwent VATS, 3 (1%) received a conversion thoracotomy. Eighty-two nodules could not be diagnosed by CTGB and 257 were surgically diagnosed without the use of CTGB. The extension of lung resection was excision in 329 cases, segmentectomy in 7 cases, and lobectomy in 3 cases. There were no mortalities in the surgical cases, while a single (0.3%) case had an operative complication, postoperative bleeding that required a re-thoracotomy. We performed CTGB only after receiving informed consent, as an air embolism is a severe complication that can lead to death [5] and implantation of malignant cells can lead to recurrence [6]. The CTGB procedures were carried out using a 22-gauge needle and showed a post-operative complication rate of 14% (20/140), including 19 (13%) cases of pneumothorax and 1 (0.7%) of hemoptysis.
FFB was able to diagnose 67% (990/1487) of all nodules and the area under the ROC curve was 0.74 (0.72<95% CI <0.77) (Fig. 2). The ratios of successful diagnosis using FFB for tumors sized between 0 cm and 1.0 cm, 1.0 and 1.5 cm, 1.5 and 2.0 cm, and greater than 2.0 cm were 0% (0/58), 16% (19/115), 35% (59/141), and 97% (1072/1173), respectively (P<0.0001) (Fig. 3). Based on our results, we concluded that there was little difference in the possibility of diagnosis among the various tumor locations. Tumor location was the right upper lobe in 544 cases, right middle lobe in 92 cases, right lower lobe in 269 cases, left upper lobe in 399 cases, left lower lobe in 147 cases, and unknown in 56 cases. Further, the number of lesions diagnosed using FFB in the right upper lobe was 351 (65%), while it was 69 (64%) in the right middle lobe, 175 (65%) in the right lower lobe, 280 (70%) in the left upper lobe, and 105 (71%) in the left lower lobe. In addition, diagnosis was possible for 45/248 (18%) benign lesions and 945/1212 (83%) malignant lesions. CTGB was carried out in 9% (139/1147) of the cases and the area under the ROC curve was 0.95 (0.92<95% CI <0.98) (Fig. 4). Ratios of successful diagnosis by CTGB using the same size categories as for FFB were 0% (0/25), 7% (2/29), 21% (5/24), and 84% (53/63), respectively (P<0.0001) (Fig. 5).
The area under the curve is 0.95 (0.92<95% CI <0.98). CI: confidence interval.
4. Discussion
An FFB is a relatively low risk procedure with an overall complication rate of 5%, including a mortality rate of 0.24%, though its diagnostic success for an SPN is dependent on tumor size [7]. Swenson et al. [8] found that the success rate for malignant lesions less than 1.5 cm in diameter was 10%, while it rose to between 40% and 60% for those between 2 and 3 cm in diameter. Thus, that method is considered to have limited utility and few benefits for patients with a pulmonary nodule less than 1.5 cm in diameter. That was confirmed in our study, as the ratio for successful diagnosis using FFB for tumors sized between 0 and 1.0 cm and those from 1.0 to 1.5 cm was 0% (0/58) and 16% (19/115), respectively. Therefore, FFB is not recommended for patients with an SPN smaller than 1.5 cm in diameter.
Ultra-thin bronchoscopy is generally utilized for direct visualization of more peripheral lesions in small airways, as it allows visualization of airways to the ninth generation [4]. This technique has been used experimentally, however, whether it provides a clinically significant increase in sensitivity remains unclear.
CTGB is another technique that should be considered for patients with an SPN, as it has a reported diagnostic success ratio of up to 95% for peripheral pulmonary lesions [9], though previous investigations have shown false-negative rates ranging from 3% to 29%. In addition, for a small-sized SPN less than 2 cm in diameter, CTGB was reported to have a success rate of approximately 60% [10]. However, those studies noted complication rates higher than those for a bronchoscopy, such as an up to 30% incidence of pneumothorax, though many of the patients did not require chest tube drainage. In addition, an air embolism, though rare, is a severe complication that can cause death [5], while another potential complication is implantation of malignant cells that can lead to recurrence [6], which may be due to those cells being spread through the needle tract [10]. As a result, we only perform CTGB after receiving informed consent from the patient.
A lesion that cannot be diagnosed as benign using FFB, CTGB, or both requires careful radiographic follow-up, as well as additional diagnostic tests such as a positron emission tomography (PET) scan or thoracotomy, because of possible false-negative results.
A PET scan has been used in many investigations for differentiation between benign and malignant SPNs [11], and its sensitivity and specificity for those has been shown to range from 89 to 100% and 79 to 100%, respectively, with diagnostic accuracy reported to range from 89 to 100%. However, false-negative results can occur in association with bronchiolo-alveolar carcinomas, carcinoids, and tumors less than 1 cm in diameter [12,13]. Therefore, surgery is strongly recommended for patients with a small-sized SPN less than 1 cm in diameter.
A thoracotomy is the most accurate technique for diagnosis of an SPN and when performed for patients with malignant pulmonary nodules, the technique has shown an operative mortality of 3 to 7% and resectability rates ranging from 80 to 100%, while resection of benign nodules has a reported mortality of less than 1% [14]. VATS offers the benefits of low rates of perioperative morbidity and mortality [1]. Further, both thoracotomy and VATS have specific advantages, as a residual lobectomy can be carried out if frozen section histology results lead to a diagnosis of malignancy during the operation. In addition, patients with non-small cell lung cancer diagnosed using a trans-pleural technique have a better long-time survival rate than those whose diagnosis was made with FFB [15].
Only a few studies have been performed regarding SPN breakpoint size for thoracotomy or VATS, though the results would be useful for practicing surgeons. The present findings revealed that the diagnostic success ratios without tumor excision in 1478 patients who had undergone an FFB technique for nodules sized between 0 and 1.0 cm, 1.0 and 1.5 cm, 1.5 and 2.0 cm, and greater than 2.0 cm were 0%, 14%, 37% and 91%, respectively.
Although our study has some limitations, these results from a large patient population should be helpful to provide further direction for investigation. In addition, the data will be useful for both physicians and surgeons. As a result of our findings, surgery for diagnosis of nodules using a thoracotomy or VATS may be recommended for operable patients with a small SPN sized less than 1.5 cm in diameter and optimal for patients with an SPN smaller than 1.0 cm in diameter. However, a prospective study would be helpful to elucidate the optimal strategy for patients with an SPN.
References
Landreneau RJ, Hazelrigg SR, Ferson PF, Johnson JA, Nawarawong W, Boley TM, Curtis JJ, Bowers CM, Herlan DB, Dowling RD. Thoracoscopic resection of 85 pulmonary lesions. Ann Thorac Surg 1992; 54:415–420.
Gasparini S, Ferretti M, Secchi EB, Baldelli S, Zuccatosta L, Gusella P. Integration of transbronchial and percutaneous approach in the diagnosis of peripheral pulmonary nodele or masses. Chest 1995; 108:131–137.
Schriber G, McCrory DC. Performance characteristics of different mordalities for diagnosis of suspected lung cancer. Chest 2003; 123:115s–128s.
Tanaka M, Takizawa H, Satho M, Okada Y, Yamasawa F, Umeda A. Assessment of an ultrathin bronchoscope that allows cytodiagnosis of small airways. Chest 1994; 106:1443–1447.
Aberle DR, Gamsu G, Golden JA. Fatal systemic arterial air embolism following lung needle aspiration. Radiology 1987; 165:351–353.
Kim JH, Kim YT, Lim HK, Kim YH, Sung SW. Management for chest wall implantation of non-small cell lung cancer after fine-needle aspiration biopsy. Eur J Cardiothorac Surg 2003; 23:828–832.
Wallance JM, Deutsch AL. Flexible fiberoptic bronchoscopy and percutaneus needle lung aspiration for evaluating the solitary pulmonary nodule. Chest 1982; 81:655–671.
Swensen SJ, Jett JR, Payne WS, Viggiano RW, Pairolero PC, Trastek VF. An integrated approach to evaluation of the solitary pulmonary nodule. Mayo Clin Proc 1990; 65:173–186.
Berquist TH, Bailey PB, Cortese DA, Miller WE. Transthoracic needle biopsy: accuracy and complications in relation to location and type of lesion. Mayo Clin Proc 1980; 55:475–481.
Sawabata N, Ohta M, Maeda H. Fine-needle aspiration cytologic technique for lung cancer has a high potential of malignant cell spread through the tract. Chest 2000; 118:936–939.
Dewan NA, Gupta NC, Redepenning LS, Phalen JJ, Frick MP. Diagnostic efficacy of PET-FDG imaging in solitary pulmonary nodules: potential role in evaluation and management. Chest 1993; 104:997–1002.
Higashi K, Ueda Y, Seki H, Yuasa K, Oguchi M, Noguchi T, Taniguchi M, Tonami H, Okimura T, Yamamoto I. Fluorine-18-FDG PET imaging is negative in bronchioloalveolar lung carcinoma. J Nucl Med 1998; 39:1016–1020.
Erasmus JJ, McAdams HP, Patz EF Jr, Coleman RE, Ahuja V, Goodman PC. Evaluation of primary pulmonary carcinoid tumors using FDG-PET. AJR 1998; 170:1369–1373.
Steele JD. The solitary pulmonary nodule: report of a cooperative study of resected asymptomatic solitary pulmonary nodules in males. J Thorac Cardiovasc Surg 1963; 46:21–39.
Sawabata N, Maeda H, Ohta M, Nakagawa M. Operable non-small cell lung cancer diagnosed by transpleural techniques: do they affect relapse and prognosis. Chest 2001; 120:1595–1598.(Noriyoshi Sawabata, Soich)