Correspondence Acta Radiologica 54(10) 1150–1151 ! The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0284185113502476 acr.sagepub.com
Computed tomography-guided needle biopsy of lung lesions: is fine needle aspiration really more accurate than core needle biopsy? In a recent article published in Acta Radiologica, Poulou and colleagues report on the diagnostic yield of computed tomography (CT)-guided transthoracic needle biopsy (TNB) of lung lesions (1). In that study involving 1000 procedures, performed by using fine needle aspiration ([FNA] 64% of all procedures), core needle biopsy ([CNB] 25%), or both (11%), the authors found that CNB had an adverse impact on diagnostic yield compared to FNA and concluded that performing CNB alone is not warranted. Conversely, previous studies demonstrated that, compared to FNA, CNB achieves better diagnostic accuracy for benign lesions (71–97% vs. 31–70%) and comparable high accuracy for malignant tumours (>90%) (2–5). This discrepancy could be related to some key issues in the design of Poulou’s retrospective study which are potentially troubling and could have influenced its results. First, needle type selection (FNA, CNB, or their combination) was based on the radiologist’s subjective judgement and two samples were obtained for each procedure to reduce inadequate sampling rate in the absence of a pathologist on-site. Nevertheless, previous studies demonstrated that, compared to single sampling, multiple passes in the lesion without immediate cytological assessment do not increase diagnostic accuracy of CT-guided FNA, that represents twothirds of all procedures (3,5). Furthermore, previous investigators demonstrated the operator’s inability to assess visually the adequacy of samples obtained with FNA (3). The presence of a pathologist on-site, to confirm that diagnostic material has been obtained by FNA, has been shown to improve diagnostic yield, especially for benign lesions (3). If this resource is not available, it has been suggested that CNB should be obtained routinely (4). Second, the authors reported that a definitive diagnosis was obtained in 960/994 (96.6%) procedures. Among definitive diagnoses, 47.3% (454 procedures)
were negative for malignancy although most of these (425/454, 93.6%) were considered negative results but non-specific, since a specific benign diagnosis was not obtained at time of TNB. A negative and specific result of benign disease was obtained only in 29/454 (6.4%) procedures. For non-specific benign diagnoses, the cytological/histological finding of specimens was not defined (samples with non-specific benign or inflammatory cells and/or without malignant cells?) and the gold standard used as reference was not clearly stated (final diagnosis obtained through additional investigations or radiological follow-up with lesion regression after antibiotic therapy?). To validate their conclusion (better diagnostic yield of FNA compared to CNB in the setting of CT-guided TNB with no immediate cytological assessment), the authors should report the number of non-specific negative results obtained respectively with the use of FNA and CNB, and should prove with statistical significance that a higher percentage of non-specific benign diagnoses was obtained with CNB or that no difference was appreciable. Conversely, considering the higher accuracy of CNB compared to FNA in the absence of immediate cytological assessment and for benign lesions (that in Poulou’s study represent 47.3% of all lesions) reported in literature, we do not exclude that a higher percentage of non-specific negative diagnoses was obtained by using FNA rather than CNB. By excluding these cases as definitive diagnoses at time of TNB, we suppose that CNB is not less reliable than FNA. On the contrary, in keeping with the findings of previous studies, we believe that CNB is more accurate than FNA in centers where immediate cytological assessment is not available, especially in obtaining specific benign diagnoses (2–5). At last, as reported by Poulou, a non-specific benign result with no further characterization does not exclude malignancy, and should be avoided as frequently as possible since in this condition further investigations and/ or follow-up are required (1). In Poulou’s study, extensive clinical and radiological follow-up, due to the high rate of non-specific benign diagnoses to exclude their malignancy, could result in considerable additional costs.
Priola and Priola References 1. Poulou LS, Tsagouli P, Ziakas PD, et al. Computed tomography-guided needle aspiration and biopsy of pulmonary lesions: a single-center experience in 1000 patients. Acta Radiol 2013;54:640–645. 2. Priola AM, Priola SM, Cataldi A, et al. Diagnostic accuracy and complication rate of CT-guided fine needle aspiration biopsy of lung lesions: a study based on the experience of the cytopathologist. Acta Radiol 2010;51:527–533. 3. Austin JHM, Cohen MB. Value of having a cytopathologist present during percutaneous fine-needle aspiration biopsy of lung: report of 55 cancer patients and metaanalysis of literature. Am J Roentgenol 1993;160:175–177. 4. Montaudon M, Latrabe V, Pariente A, et al. Factors influencing accuracy of CT-guided percutaneous biopsies of pulmonary lesions. Eur Radiol 2004;14:1234–1240. 5. Ku¨c¸u¨k CU, Yilmaz A, Yilmaz A, et al. Computed tomography-guided transthoracic fine-needle aspiration in
1151 diagnosis of lung cancer: a comparison of single-pass needle and multiple-pass coaxial needle system and the value of immediate cytological assessment. Respirology 2004;9:392–396.
Adriano Massimiliano Priola and Sandro Massimo Priola Department of Diagnostic and Interventional Radiology, San Luigi Gonzaga University Hospital, Orbassano, Torino, Italy Corresponding author: Adriano Massimiliano Priola, Department of Diagnostic and Interventional Radiology, Regione Gonzole 10, San Luigi Gonzaga University Hospital, Orbassano, Torino 10043, Italy. Email: [email protected]
Computed tomography-guided needle biopsy of lung lesions: is fine needle aspiration really more accurate than core needle biopsy? In a recent article published in Acta Radiologica, Poulou and colleagues report on the diagnostic yield of computed tomography (CT)-guided transthoracic needle biopsy (TNB) of lung lesions (1). In that study involving 1000 procedures, performed by using fine needle aspiration ([FNA] 64% of all procedures), core needle biopsy ([CNB] 25%), or both (11%), the authors found that CNB had an adverse impact on diagnostic yield compared to FNA and concluded that performing CNB alone is not warranted. Conversely, previous studies demonstrated that, compared to FNA, CNB achieves better diagnostic accuracy for benign lesions (71–97% vs. 31–70%) and comparable high accuracy for malignant tumours (>90%) (2–5). This discrepancy could be related to some key issues in the design of Poulou’s retrospective study which are potentially troubling and could have influenced its results. First, needle type selection (FNA, CNB, or their combination) was based on the radiologist’s subjective judgement and two samples were obtained for each procedure to reduce inadequate sampling rate in the absence of a pathologist on-site. Nevertheless, previous studies demonstrated that, compared to single sampling, multiple passes in the lesion without immediate cytological assessment do not increase diagnostic accuracy of CT-guided FNA, that represents twothirds of all procedures (3,5). Furthermore, previous investigators demonstrated the operator’s inability to assess visually the adequacy of samples obtained with FNA (3). The presence of a pathologist on-site, to confirm that diagnostic material has been obtained by FNA, has been shown to improve diagnostic yield, especially for benign lesions (3). If this resource is not available, it has been suggested that CNB should be obtained routinely (4). Second, the authors reported that a definitive diagnosis was obtained in 960/994 (96.6%) procedures. Among definitive diagnoses, 47.3% (454 procedures)
were negative for malignancy although most of these (425/454, 93.6%) were considered negative results but non-specific, since a specific benign diagnosis was not obtained at time of TNB. A negative and specific result of benign disease was obtained only in 29/454 (6.4%) procedures. For non-specific benign diagnoses, the cytological/histological finding of specimens was not defined (samples with non-specific benign or inflammatory cells and/or without malignant cells?) and the gold standard used as reference was not clearly stated (final diagnosis obtained through additional investigations or radiological follow-up with lesion regression after antibiotic therapy?). To validate their conclusion (better diagnostic yield of FNA compared to CNB in the setting of CT-guided TNB with no immediate cytological assessment), the authors should report the number of non-specific negative results obtained respectively with the use of FNA and CNB, and should prove with statistical significance that a higher percentage of non-specific benign diagnoses was obtained with CNB or that no difference was appreciable. Conversely, considering the higher accuracy of CNB compared to FNA in the absence of immediate cytological assessment and for benign lesions (that in Poulou’s study represent 47.3% of all lesions) reported in literature, we do not exclude that a higher percentage of non-specific negative diagnoses was obtained by using FNA rather than CNB. By excluding these cases as definitive diagnoses at time of TNB, we suppose that CNB is not less reliable than FNA. On the contrary, in keeping with the findings of previous studies, we believe that CNB is more accurate than FNA in centers where immediate cytological assessment is not available, especially in obtaining specific benign diagnoses (2–5). At last, as reported by Poulou, a non-specific benign result with no further characterization does not exclude malignancy, and should be avoided as frequently as possible since in this condition further investigations and/ or follow-up are required (1). In Poulou’s study, extensive clinical and radiological follow-up, due to the high rate of non-specific benign diagnoses to exclude their malignancy, could result in considerable additional costs.
Priola and Priola References 1. Poulou LS, Tsagouli P, Ziakas PD, et al. Computed tomography-guided needle aspiration and biopsy of pulmonary lesions: a single-center experience in 1000 patients. Acta Radiol 2013;54:640–645. 2. Priola AM, Priola SM, Cataldi A, et al. Diagnostic accuracy and complication rate of CT-guided fine needle aspiration biopsy of lung lesions: a study based on the experience of the cytopathologist. Acta Radiol 2010;51:527–533. 3. Austin JHM, Cohen MB. Value of having a cytopathologist present during percutaneous fine-needle aspiration biopsy of lung: report of 55 cancer patients and metaanalysis of literature. Am J Roentgenol 1993;160:175–177. 4. Montaudon M, Latrabe V, Pariente A, et al. Factors influencing accuracy of CT-guided percutaneous biopsies of pulmonary lesions. Eur Radiol 2004;14:1234–1240. 5. Ku¨c¸u¨k CU, Yilmaz A, Yilmaz A, et al. Computed tomography-guided transthoracic fine-needle aspiration in
1151 diagnosis of lung cancer: a comparison of single-pass needle and multiple-pass coaxial needle system and the value of immediate cytological assessment. Respirology 2004;9:392–396.
Adriano Massimiliano Priola and Sandro Massimo Priola Department of Diagnostic and Interventional Radiology, San Luigi Gonzaga University Hospital, Orbassano, Torino, Italy Corresponding author: Adriano Massimiliano Priola, Department of Diagnostic and Interventional Radiology, Regione Gonzole 10, San Luigi Gonzaga University Hospital, Orbassano, Torino 10043, Italy. Email: [email protected]
