CT-guided Percutaneous Fine-needle Aspiration Research Articles

Comparison of core needle biopsy and fine-needle aspiration methods in CT-guided percutaneous sampling of pancreatic tumors.

To compare the diagnostic efficacy and safety of CT-guided percutaneous core needle biopsy (CNB) and fine-needle aspiration (FNA) for pancreatic lesions. A total of 176 patients with 176 pancreatic lesions who visited our hospital between January 2016 and March 2021 were retrospectively analyzed. They were divided into three groups: FNA group A (<1.5 cm between the lesion and great vessels necessitating FNA), FNA group B, and CNB (the latter two with ≥1.5 cm between the lesion and great vessels necessitating FNA). The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and postoperative. The statistical analysis was done using Statistical Package for the Social Sciences version 17.0. One hundred and seventy six patient's specimens all met the requirements. There were no statistically significant differences in sensitivity, specificity, positive predictive value, negative predictive value, and accuracy between the CNB group and FNA group B, (P > 0.05). Thirteen samples submitted for genetic testing (5 in CNB group, 4 in each of the FNA groups A and B) all met the standards of next-generation sequencing gene detection. The main complications of these groups included abdominal pain, fever, and hyperamylasemia. CT-guided percutaneous FNA and CNB have similar diagnostic efficacy for pancreatic biopsy. Furthermore, FNA has a wide range of puncture indications and is very safe. Like CNB, the obtained tissue through FNA can be genetically tested to guide clinical treatment.

Efficacy and safety of CT-guided percutaneous fine needle aspiration and biopsy for malignant pulmonary lesions

Background: CT-guided percutaneous transthoracic fine needle aspiration (FNA) and core biopsy (CB) are commonly used to characterise lung lesions. There is conflicting information on which method is superior and wide variation in reported complication rates. Our objectives were to establish the efficacy and safety of percutaneous CT-guided FNA and CB in the diagnosis of malignant lung lesions. Methods: This retrospective study included patients who underwent CT-guided percutaneous FNA and/or CB for lung parenchymal lesions at Kasturba Medical College Mangalore, from January 2013 to December 2020. Ethical clearance was obtained from the Institutional Ethics Committee. Efficacy was determined by the adequacy of samples, sensitivity, specificity and diagnostic accuracy. Safety was assessed using the incidence of complications. Results: A total of 326 patients underwent both FNA and CB, and 49 underwent FNA alone. Adequate samples were obtained in 82.9% of FNA cases and 95.7% of CB cases. Considering biopsy as the gold standard, the sensitivity, specificity and diagnostic accuracy of FNA for malignancy were 95.19%, 80% and 91.27%, respectively. Kappa agreement between the two methods was substantial (0.767). Pneumothorax was the only complication observed, and was seen in 31 patients (8.2%), of which only one required chest tube drainage. The incidence of pneumothorax was significantly higher in patients with pre-existing lung disease such as COPD/emphysema (p value 0.000), patients with smaller lesions (p = 0.009), and deeper lesions from the pleura (p &lt;0.0001). Conclusions: FNA and CB are both safe and effective procedures. In the absence of an onsite cytopathologist, we recommend a combination of both techniques.

Diagnostic Value of Rapid On-Site Evaluation for CT-Guided Percutaneous Fine Needle Aspiration in the Diagnosis of Pulmonary Occupying Lesions

Objective Rapid on-site evaluation (ROSE) is an effective and efficient auxiliary examination, but its value for CT-guided percutaneous fine-needle aspiration (FNA) in the diagnosis of pulmonary occupying lesions is unclear. This study is aimed at evaluating the clinical utility of ROSE for CT-guided percutaneous FNA. Methods We reviewed 234 patients from September 2018 to April 2019. The result using ROSE was compared with the final pathological diagnosis of CT-guided percutaneous FNA, and we also compared the complications between the ROSE group and the NO-ROSE group. The final pathological diagnosis results served as the gold standard. We also analyzed the diagnostic rate of FNA and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of malignancy. The correlation between diverse pathological types of lung cancer was also taken into consideration. Results In total, 132 patients underwent CT-guided percutaneous FNA with ROSE (ROSE group), and 102 did not (NO-ROSE group). The diagnostic rate, sensitivity, specificity, PPV, and NPV of the ROSE group were 91.6%, 89.1%, 94.1%, 93.4%, and 90.1%, respectively. The complication rates of the ROSE group and the NO-ROSE group were 8.33% and 16.67%, respectively. This difference was not statistically significant (P > 0.05). In subsets of adenocarcinoma (AC) and small cell lung cancer (SCLC) patients, the ROSE result was highly consistent with the final pathological result. Conclusion CT-guided percutaneous FNA combined with ROSE has a high diagnostic rate, sensitivity, and specificity for pulmonary occupying lesions and an acceptable rate of complications. This method is worthy of wide use given its high efficiency and safety.

Clinical value of CT-guided percutaneous fine-needle aspiration biopsy for peritoneal lesions

BackgroundTo investigate the clinical value of CT-guided percutaneous fine-needle aspiration biopsy for peritoneal lesions of unknown nature.MethodsA retrospective analysis was conducted of 84 patients with peritoneal thickening for unknown reasons. There were 26 males and 58 females who underwent CT-guided percutaneous fine-needle aspiration biopsy for peritoneal lesions.ResultAmong these 84 patients, no definite pathologic diagnosis was made in 3 patients, who were lost to the follow-up. The accuracy rate of CT-guided percutaneous fine-needle aspiration biopsy was 95.1% (77/81). Sixty lesions were pathologically-diagnosed with malignancies (74.1%), including 55 with peritoneal metastases, 4 with malignant mesotheliomas, and 1 with a lymphoma. Twenty-four patients (33.8%) were diagnosed as benign lesions, including 11 with tuberculosis and 13 with inflammatory lesions. The complications of CT-guided percutaneous fine-needle aspiration biopsy included bleeding in 1 patient and ascites leakage in 2 patients.ConclusionCT-guided percutaneous fine-needle aspiration biopsy is a safe and effective method for diagnosing peritoneal lesions.

Mediastinal paraganglioma successfully resected by robot-assisted thoracoscopic surgery with en bloc chest wall resection: a case report

BackgroundRobot-assisted thoracoscopic surgery (RATS) is useful for surgery in the apical region of the chest cavity, as it narrows towards the head. Here, we describe a nonfunctional, rib-invasive paraganglioma arising in the posterior mediastinum that was successfully removed using RATS combined with chest wall resection.Case presentationA 31-year-old woman presented with a posterior mediastinal mass on chest computed tomography (CT) scan during a medical check-up 2 years prior. Positron emission tomography/computed tomography scan with F-18 fluorodeoxyglucose revealed a mass associated with standardized uptake maximum value of 2.69. With a preoperative diagnosis of neurogenic tumor by CT-guided percutaneous fine-needle aspiration biopsy, we performed robot-assisted tumor resection combined with chest wall resection. The wristed instruments of the robotic surgical system have increased range of motion and enabled the tumor resection without organ injury in the thoracic cavity. Histopathology examination revealed a non-functional paraganglioma with rib invasion.ConclusionsRATS is a useful technique, enabling safer and easier resection of a mediastinal tumor adjacent to surrounding organs.

Bilateral benign renal oncocytomas and the role of renal biopsy: single institution review

BackgroundThe goal was to assess the natural history and management of patients with pathologically proven bilateral (synchronous) RO after undergoing initial partial nephrectomy (PN).MethodsAll patients underwent either robotic/laparoscopic or open PN by two experienced genitourinary oncologists from 2005–2013. Final pathology was determined by surgical excision, CT-guided percutaneous core biopsy (CT-biopsy) or fine needle aspiration (FNA). Patient demographics, tumor characteristics (pathologic data, location, size) type of surgery, pre/post estimated glomerular filtration rate (eGFR) and surgical complications were recorded.ResultsTwelve patients were identified with bilateral RO. Median age at the time of surgery was 68 years (46–77) (Table 1). The median size of the largest tumor(s) resected was 2.75 cm (1.5–5.5 cm) and second largest tumor(s) was 1.75 cm (1.0–4.0 cm). Four patients underwent bilateral staged PN and one patient underwent simultaneous bilateral PN (horseshoe kidney). Two patients underwent RFA at the time of biopsy of the contralateral mass after PN. Five patients underwent CT-bx/FNA (5/5) of the contralateral mass followed by active surveillance.Mean follow up was 34 months. There was no significant change in median creatinine pre- and post-operatively. One patient was lost to follow up and one patient died of unknown causes 5 years post-operatively. eGFR decreased an average of 16.96% post-operatively, including a single patient whose eGFR increased by 7.8% after surgery and a single patient whose eGFR did not change (Table 2).ConclusionsPatients with bilateral renal masses and pathologically proven RO can be safely managed with active surveillance after biopsy confirmation of the contralateral mass.

Extra-pleuric coaxial system for CT-guided percutaneous fine-needle aspiration biopsy (FNAB) of small (≤20mm) lung nodules: a novel technique using multiplanar reconstruction (MPR) images.

The aim of the study is to present the diagnostic feasibility, usefulness, and safety of a novel technique for coaxial CT-guided fine-needle aspiration biopsy of small (≤20mm in diameter) lung nodules. A 18-gauge (G) (1.2×40mm) needle is inserted through the skin in the depth of the thoracic wall tissues remaining outside the pleura. Its positioning is planned and adjusted using multiplanar reconstruction (MPR) images along the 18-G guide needle axis tracing a reference outline extended from the needle tip to the target nodule. When the insertion of the 18-G extra-pleuric needle (EPN) proves to be precise, a 22-G Chiba needle is then passed through the outer 18-G EPN until it reaches the thoracic lesion for the sampling procedure. Patient population included 153 males and 94 females, with a mean age of 61.3±21.6years. Mean nodule diameter was 14.1±2.2mm. The lesion depth from pleural plane ranged from 0mm to 127mm. An average of 1.29 aspirates were performed per lesion. The most common complication was pneumothorax in 27 cases; there were no cases of PNX requiring chest tube insertion. Intrapulmonary bleeding along the needle track was observed in 32 patients. Exploiting the advantage of MPR images, our novel technique of extra-pleuric coaxial system with a 18-G EPN allows the operator to multiple samplings of small (≤20mm) target lesions in various locations with a thinner (22-G Chiba) needle, thus reducing the degree of pleural, parenchymal, or adjacent organs damage.

The diagnostic accuracy of CT-guided percutaneous core needle biopsy and fine needle aspiration in pulmonary lesions: a meta-analysis

To determine and compare the diagnostic value of computed tomography (CT)-guided percutaneous core needle biopsy (PCNB) and percutaneous fine-needle aspiration biopsy (PNAB) in pulmonary lesions. PubMed, EMBASE, and the Web of Science were systematically searched for relevant studies that investigated the diagnostic accuracy of CT-guided PCNB and/or PNAB for pulmonary lesions up to December 2014. After study selection, data extraction, and quality assessment, the sensitivity (SEN), specificity (SPE), diagnostic odds rate (DOR), positive likelihood ratios (PLR), negative likelihood ratios (NLR), and summary receiver operating characteristic (SROC) curves were calculated using the Meta-Disc 1.4 software. Nineteen publications, including 21 independent studies, met the inclusion criteria. Of them, 15 studies were included in the PCNB group and six studies in the PNAB group. The pooled SEN, SPE, DOR, PLR, NLR, and SROC were 0.95, 0.99, 54.72, 0.06, 821.90, and 0.98 in the PCNB group and 0.90, 0.99, 24.71, 0.14, 210.72, and 0.98 in the PNAB group, respectively. Based on current evidence, both PCNB and PNAB can be used as diagnostic methods to distinguish benign and malignant pulmonary lesions; the difference between PCNB and PNAB regarding diagnostic accuracy of benign or malignant pulmonary lesions is not obvious.

CT-Guided Percutaneous Fine Needle Aspiration Cytology of Pulmonary Mass.

Introduction: Following the first study of Computed tomography guided trans thoracic biopsy of lung lesion by Haaga and Alfidi in 1976, CT guided transthoracic biopsy has been widely used for confirming the diagnosis of suspicious lung lesions. This study is aimed to assess the effectiveness of Transthoracic percutaneous fi ne needle aspiration cytology and frequency of associated complications. Methods: A retrospective, hospital based study was performed between 11/06/2008 and 1/12/2009 at Department of Radiology, Shree Birendra Hospital, Kathmandu, Nepal. Thirty nine consecutive cases of lung lesions who underwent Trans Thoracic Percutaneous Fine Needle Aspiration Cytology (TTFNAC) under CT guidance were analysed. Smears of the aspirated material were evaluated by the pathology consultant (cytopathological evaluation) for adequacy. Results: There was adequate material for a cytopathological diagnosis in thirty four (87.18 %) cases. Two cases were hemorrhagic while three cases revealed only reactive cells thus inadequate and non representative case constituted (12.8 %). Eight cases were reported as benign (23.53 %). Twenty three samples (67.65%) were reported as definite malignant cases and three cases (8.82%) showed atypical cells, suggestive of malignancy. Squamous cell carcinoma was the single most frequent histological diagnosis (12 cases). Conclusions: The FNAC of lung is useful, safe and economical technique providing 87% diagnostic accuracy for lung mass without significant increase in complications. Medical Journal of Shree Birendra Hospital; Jan-June 2012/vol.11/Issue1/37-41 DOI: http://dx.doi.org/10.3126/mjsbh.v11i1.7766

Quality assurance of rapid on-site evaluation of CT-guided fine-needle aspiration cytology of lung nodules

The methods available for the diagnosis of lung cancer include radiologic, cytologic and pathologic procedures. The aim of this study was to determine the quality assurance of CT guided fine needle aspiration cytology of lung nodules. Cytology results were rated to 4 categories (positive; suspicious; negative; not representative). All cytology reports were compared with the final histology diagnosis. A total of 128 patients underwent CT-guided percutaneous fine-needle aspiration biopsy cytology (63 males; 65 females; mean age 62.8 years). Smears were adequate in 99 cases and inadequate in 29 cases. The average diameter of the nodules was 3.28 cm. Thirty three (25.6%) of the cases were histologically verified and 2 falsely negative and 2 falsely positive cases were detected. The sensitivity and the positive predictive value were 88.8% and 88.8%, respectively. Pneumothorax developed in 7 (5.4%) cases. These results suggest that CT-guided transthoracic fine needle aspiration cytology has a high diagnostic accuracy and an acceptable complication rate. The auditing valves of the results meet the proposed threshold values.

Biópsia aspirativa transtorácica por agulha fina guiada por TC de lesões pulmonares: resultados e complicações

To analyze the cytological findings of CT-guided percutaneous fine-needle aspiration biopsies of the lung, to demonstrate the diagnostic feasibility of the method in the investigation of pulmonary lesions, and to determine the complications of the procedure, evaluating its safety. A retrospective analysis of 89 patients with various types of pulmonary lesions who underwent 97 procedures over a period of five years. The patients were divided into groups regarding the indication for the procedure: suspicion of primary lung cancer (stages IIIB or IV); suspicion of lung cancer (stages I, II, or IIIA) and clinical contraindications for surgery; suspicion of pulmonary metastasis from other organs; and pulmonary lesions with benign radiological aspect. All of the procedures were performed with 25-gauge needles and were guided by spiral CT. The final diagnosis was confirmed by surgical biopsy and clinical/oncological follow-up. For the analysis of complications, the total number of procedures was considered. The main indication for the procedure was suspicion of advanced-stage primary lung cancer. The accuracy of the method for malignant lesions was 91.5%. The lesion was confirmed as cancer in 73% of the patients. The major complication was pneumothorax (27.8%), which required chest tube drainage in 12.4% of the procedures. The principal indication for CT-guided fine-needle biopsy was suspicion of primary lung cancer in patients who were not surgical candidates. The procedure has high diagnostic feasibility for malignant pulmonary diseases. The most prevalent complication was pneumothorax. However, in most cases, chest tube drainage was unnecessary. No deaths were related to the procedure.

Predictive complication factors for ct-guided fine needle aspiration biopsy of pulmonary lesions

OBJECTIVE:Distinct aspects can influence the complication rates of computed tomography‐guided percutaneous fine needle aspiration biopsy of lung lesions. The purpose of the current study is to determine the influence of radiological techniques and clinical characteristics in predicting complications from this procedure.SUBJECTS AND METHODS:A retrospective study was developed involving 340 patients who were submitted to a consecutive series of 362 computed tomography‐guided fine needle aspiration biopsies of lung lesions between July 1996 and June 2004, using 22‐gauge needles (CHIBA). Variables such as the radiological characteristics of the lesions, secondary pulmonary radiological findings, co‐morbidities, and aspects concerning the procedure were studied.RESULTS:The diameters of the lung lesions varied from 9 to 140 mm, with a mean of 51.5 ± 24.3 mm and median of 40 mm. The depth of the lesions varied from 10 mm to 130 mm, with a mean of 44 ± 20.9 mm, and median median of 52 mm. Complications occurred in 52 (14.4%) cases, pneumothorax being the most frequent, with 40 (11.1%) cases, followed by hemoptisis with 7 (1.9%) cases, and hematoma with 4 (1.1%) cases. Lesions that did not contact the pleura, with normal pulmonary tissue interposition between lesion and pleura, had higher complication rates, with 22 (22%) cases, than lesions that contact the pleura, with 6 (9%) cases, with a statistically significant difference (p = 0.03).CONCLUSIONS:CT‐guided percutaneous fine needle aspiration biopsy of lung lesions had a lower rate of complications in our study and presented more rates of complications on lesions that lack pleural contact.

Hyalinizing Granuloma: An Unusual Case of a Pulmonary Mass

We describe the case of pulmonary hyalinizing granuloma in a 34-year-old asymptomatic man who presented with a pulmonary nodule apparent by chest radiography and computed tomography (CT). He had a history of previous treatment for tuberculosis. His laboratory data were normal. Bronchoscopy and CT-guided percutaneous transthoracic fine needle aspiration cytology were inconclusive. The diagnosis was revealed after the histopathological examination of an open lung biopsy.

Computed Tomography–Guided Percutaneous Needle Biopsy of Pulmonary Nodules: Impact of Nodule Size on Diagnostic Accuracy

Purpose This study was undertaken to compare the diagnostic accuracy and complication rate of computed tomography (CT)—guided percutaneous lung biopsies of lung nodules ≤ 1.5 cm versus > 1.5 cm in diameter. Patients and Methods A total of 139 patients (age range, 18-89 years; mean, 62.5 years) underwent CT-guided percutaneous fine-needle aspiration biopsy or 20-gauge core biopsy using an automated biopsy gun. In 37 patients, the lung nodule measured ≤ 1.5 cm (mean, 1.1 cm), and in 102 patients, the lung nodule was > 1.5 cm (mean, 2.8 cm). Diagnostic accuracy was determined by cytopathology results. Major and minor complications were documented. Results Overall diagnostic accuracy, pneumothorax rate, and thoracostomy tube insertion rates were 67.6%, 34.5%, and 5%, respectively. Of the 98 patients with malignancy, 77 patients (78.6%) had a definite diagnostic biopsy. Overall, nodules > 1.5 cm were statistically more likely to result in a diagnostic specimen (73.5%) than nodules ≤ 1.5 cm (51.4%; P = .012). Similarly, diagnostic accuracy for malignancy was higher in nodules > 1.5 cm than in those ≤ 1.5 cm (81.3% vs. 69.6%); however, this was not statistically significant. There was no correlation between nodule size and the incidence of complications. Conclusion Overall, diagnostic accuracy of CT-guided percutaneous lung biopsy of lung nodules ≤ 1.5 cm is slightly lower than that of nodules > 1.5 cm. However, the diagnostic accuracy for malignancy is high in both groups, with a low risk of complications

Nodular pulmonary amyloidosis with an unusual protein composition diagnosed by fine‐needle aspiration biopsy: A case report

Nodular pulmonary amyloidosis is rare, but a number of individual cases have been reported in the literature. Radiologically, pulmonary amyloid nodules often mimic cancer and hence require biopsy to obtain a specimen for definitive diagnosis. We describe a case of isolated nodular pulmonary amyloidosis with an unusual amyloid composition that given the patient's clinical history has not been described in the literature to the best of our knowledge, making this case unique. A 58-year-old woman with a history of mixed connective tissue disease was found to have multiple lung nodules on chest computed tomography (CT) that were radiologically suspicious for cancer. A CT-guided percutaneous fine-needle aspiration (FNA) biopsy of one of the nodules was performed. A diagnosis of amyloid was rendered using special stains and polarized light microscopic examination. Immunohistochemical stains revealed that the amyloid comprised beta-2 microglobulin as well as both kappa and lambda light chains. Further work up showed no evidence of systemic amyloidosis. We were successful in rendering an accurate diagnosis of a pulmonary amyloidoma on material procured by CT-guided FNA thus avoiding more invasive procedures. In addition, immunohistochemical staining revealed an unexpected and highly unusual protein composition of the amyloid.

CT-Guided Percutaneous Fine-Needle Aspiration Biopsy of the Inferior Vena Cava Wall: A Posterior Coaxial Approach

A 72-year-old man was referred to our department with an incidentally diagnosed bronchogenic carcinoma of the right upper lobe. Positron emission tomography (PET) combined with computed tomography (PET-CT) revealed an unexpected hot spot in the ventral wall of the infrarenal segment of the inferior vena cava (IVC). Diagnostic biopsy of this lesion was performed under CT guidance with semiautomated 20G fine-needle aspiration (FNA) through a 19G coaxial needle. Cytology revealed few carcinoma cells, which led to the remarkable diagnosis of a distant metastasis to the IVC wall. Both the immediate postinterventional CT control and the further surveillance period of the patient were unremarkable; in particular, no signs of bleeding complications were detected. We conclude that coaxial FNA of an IVC wall lesion is technically feasible and may even help diagnose distant metastasis.

CT-guided percutaneous fine-needle aspiration biopsy of pulmonary nodules measuring 10 mm or less

To determine the value of computed tomography (CT)-guided fine-needle aspiration biopsy (FNAB) of small pulmonary nodules measuring 10 mm or less. CT-guided FNABs of 55 nodules, measuring 10mm or less, were performed between January 2003 and February 2006. A coaxial technique was used, with an outer 19 G Bard Truguide needle and inner 22 G disposable Greene biopsy needle. Adequacy of specimens was assessed on-site by a cytotechnologist. The sizes of the nodules, distance from pleura, number of pleural punctures and aspirates, complications encountered, cytological diagnosis, and outcome were recorded. The mean nodule diameter was 9 mm (range 5-10 mm). The average distance from the costal pleura was 31 mm (range 0-88 mm). In 50 of the 55 FNABs, the pleura was crossed once. An average of four aspirates was performed per case. Twenty-five FNABs (45.5%) were adequate for diagnosis (24 malignant and one tuberculosis). In 11 cases, where no definite diagnosis was made following FNAB, the outcome was not affected. In 10 cases, samples were insufficient for diagnosis and the nodules were subsequently diagnosed as malignant. Eight cases were excluded in the final analysis as follow-up details were unavailable. The sensitivity for malignancy and overall accuracy were 67.7 and 78.8%, respectively. Pneumothorax occurred in 29 (52.7%) patients, with five (9.1%) requiring thoracostomy tubes. CT-guided FNAB is a useful tool in the diagnosis and management of small pulmonary nodules, despite the lower diagnostic accuracy and higher complication rate than those of larger pulmonary lesions.

P-350 CT-guided percutaneous fine-needle aspiration biopsy ofpulmonary lesions. A descriptive study

P-350 CT-guided percutaneous fine-needle aspiration biopsy ofpulmonary lesions. A descriptive study

Use of computed tomography in the diseased feline thorax.

Computed tomography (CT) scanning of the thorax is gaining more attention in veterinary medicine as therapeutic possibilities increase. Plain and contrast-enhanced CT images of the thorax of five referred cats with signs of respiratory disease were evaluated using soft tissue (pleural) and lung windows. The common CT pattern in all cats was involvement of the lung lobes, either as a homogeneous or heterogeneous single lobe hyperdensity. It involved the main bronchus, invaded the cranial or caudal mediastinum, and crossed the border to the opposite lung. Right lung atelectasis and mediastinal shift caused left lung overinflation. Bronchial lymph node enlargement was found unilaterally or bilaterally. CT-guided percutaneous fine needle aspiration biopsy of the lobar lung lesion was performed in four cats; in three cases it revealed carcinoma and in one inflammation, although the cat with suspected inflammation was subsequently found to have a carcinoma on lung lobectomy. Histopathology confirmed lung metastasis in one case and bronchial adenocarcinoma in four cases. A protocol for systematic examination of thoracic CT images is proposed.

CT-guided percutaneous fine-needle aspiration biopsy of small (< or =1-cm) pulmonary lesions.

To determine the accuracy of percutaneous computed tomography (CT)-guided fine-needle aspiration biopsy (FNAB) of small (< or =1.0-cm in diameter) pulmonary lesions. Sixty-one patients (34 men and 27 women) 21-89 years old (mean age, 61.3 years) with lung nodules 1.0 cm or smaller underwent CT-guided transthoracic FNAB. Fifty-seven of the 61 patients had an underlying primary malignancy. Maximum nodule diameters were 0.5-0.7 cm in 10 patients and 0.8-1.0 cm in 51 patients. Cytopathologic evaluation of FNAB samples was immediate in all patients. Sensitivity and accuracy were calculated, and each case was reviewed for complications, including pneumothorax and thoracostomy tube insertion. Four patients were not included in our statistical analysis because of a lack of follow-up information. FNAB samples were adequate for diagnosis in 47 (77%) of 61 patients. Diagnoses were malignancy (n = 29) or suspected malignancy (n = 3) in 52% (n = 32) and benign or atypical findings in 25% (n = 15). Findings were nondiagnostic in 23% (n = 14). Of the 29 patients without evidence of malignancy, 25 had follow-up findings available. Follow-up included chest CT in 16 patients and surgical resection in nine. Four patients were not included in statistical analysis because of a lack of follow-up information. Overall sensitivity was 82% (32 of 39); specificity, 100% (18 of 18); and diagnostic accuracy, 88% (50 of 57) on the basis of 57 patients being evaluable. Results for 47 0.8-1.0-cm lesions were considerably better (sensitivity, 88%; accuracy, 92%) than those for 10 0.5-0.7-cm lesions (sensitivity, 50%; accuracy, 70%). Sensitivity (75% vs 87%) and accuracy (87% vs 89%) also improved when comparing subpleural (< or =1.0 cm from pleural surface, n = 30) with deeper (>1 cm from pleural surface, n = 27) pulmonary lesions, but the improvement did not indicate statistical significance. Core biopsy did not reveal malignancy in any of the nine patients in whom preliminary cytologic results were inconclusive and did not improve diagnostic yield. Thirty-eight (62%) patients had pneumothorax, with 19 (31%) requiring thoracostomy tube placement. CT-guided FNAB of pulmonary lesions 1.0 cm or smaller can yield high diagnostic accuracy rates approaching those of larger lesions; FNAB of 0.8-1.0-cm lesions that are not subpleural offers the best opportunity for success.