Solitary Pulmonary Mass Research Articles

Intrapulmonary schwannoma presenting as an asymptomatic lung mass: a case report

BackgroundSchwannomas are solitary well-circumscribed encapsulated benign tumors that exhibit Schwann cell differentiation, and arise directly from myelinated peripheral or central nerves. Although they are usually asymptomatic and found incidentally, schwannomas can cause symptoms due to compression of nearby structures which, depending on the location, can make clinical presentations widely variable. Despite their rarity, schwannomas have been documented in a number of locations including the limbs, cerebellopontine angle, posterior mediastinum, and, far more infrequently, the lungs.Case presentationIn this article, we report an incidental finding of an intrapulmonary schwannoma in a 59-year-old Pakistani woman who was grossly asymptomatic upon presentation to the cardiothoracic surgery clinic. An [18F]fluorodeoxyglucose positron emission tomography/computed tomography scan revealed a lobulated soft-tissue lesion measuring 23 mm × 23 mm in the lower lobe of the right lung. A computed tomography-guided core biopsy of the mass was performed, which revealed a benign spindle cell lesion based on histopathological examination and immunohistochemical staining. The mass was surgically resected via a right lower lobectomy, and subsequently confirmed to be an encapsulated neoplastic lesion composed of well-differentiated Schwann cells. There were no short- or long-term complications, morbidities, or recurrences based on 1-year follow-up.ConclusionThis report underscores the predominantly asymptomatic nature of schwannomas and reemphasizes the efficacy of surgical resection as a safe and curative procedure for a tumor of this nature. Albeit very rare, intrapulmonary schwannomas can be considered a differential diagnosis when encountering solitary asymptomatic pulmonary nodules or masses.

Incidental Metaplastic Primary Pulmonary Meningioma.

Primary pulmonary meningioma is a rare benign tumor usually presenting as a solitary pulmonary nodule or mass. It can be easily misinterpreted as a primary lung tumor or metastases on imaging studies. We present a 54-year-old woman with an incidentally discovered solitary lung nodule, which was diagnosed as metaplastic primary pulmonary meningioma following resection. Metaplastic meningioma is a rare WHO grade 1 meningioma subtype with focal or global mesenchymal differentiation. To the authors' knowledge, primary pulmonary meningioma with mesenchymal differentiation has not been described previously in the English literature.

Differences in clinical manifestations and CT features between pulmonary actinomycosis and aspergillus nodules, as revealed by a solitary pulmonary nodule or mass

Background: Pulmonary actinomycosis is a rare bacterial disorder often misdiagnosed as other pulmonary diseases because of a lack of specific characteristics and radiographic findings. Aspergillus nodules, a common fungal infection and form of chronic pulmonary aspergillosis, have imaging findings that overlap with those of pulmonary actinomycosis. This study reviews patients’ clinical and imaging data, to differentiate pulmonary actinomycosis from Aspergillus nodules. Methods: This retrospective study included 17 patients with pulmonary actinomycosis and 25 patients with Aspergillus nodules diagnosed histopathologically in a tertiary Chinese hospital between June 2014 and January 2022. Data on age, sex, lesion types/locations, and CT findings were analyzed. Results: No significant differences were found in age (mean age 58.2 ± 7.7 vs. 57.2 ± 11.9; p = 0.76), but statistically significant differences were found in sex (men 13 vs. women 10; p = 0.02), between groups. Common symptoms between groups included cough, hemoptysis, sputum production, fever, and chest pain, which showed no significant between-group differences (p = 0.09, p = 0.28, p = 0.10, p = 1, p = 0.41, respectively). Visual evaluation revealed that pulmonary actinomycosis lesions were more likely than pulmonary aspergillosis to appear mass-like (p < 0.001), with bulky volume (p = 0.002), ill-defined margins (p = 0.045), and interlobular septal thickening (p = 0.008). Pleural changes and mediastinal or hilar lymphadenopathy were more common in pulmonary actinomycosis than in Aspergillus nodules (p = 0.037, p = 0.010, respectively), whereas cavitation, an air-crescent sign, and bronchiectasis were more common in pulmonary aspergillosis (p = 0.027, p < 0.001, p = 0.016, respectively). Conclusion: Distinguishing between pulmonary actinomycosis and Aspergillus nodules on the basis of clinical manifestations alone is difficult, although distinctive CT findings may differentiate the two diseases.

Convolutional Neural Network-Based Diagnostic Model for a Solid, Indeterminate Solitary Pulmonary Nodule or Mass on Computed Tomography.

PurposeTo establish a non-invasive diagnostic model based on convolutional neural networks (CNNs) to distinguish benign from malignant lesions manifesting as a solid, indeterminate solitary pulmonary nodule (SPN) or mass (SPM) on computed tomography (CT).MethodA total of 459 patients with solid indeterminate SPNs/SPMs on CT were ultimately included in this retrospective study and assigned to the train (n=366), validation (n=46), and test (n=47) sets. Histopathologic analysis was available for each patient. An end-to-end CNN model was proposed to predict the natural history of solid indeterminate SPN/SPMs on CT. Receiver operating characteristic curves were plotted to evaluate the predictive performance of the proposed CNN model. The accuracy, sensitivity, and specificity of diagnoses by radiologists alone were compared with those of diagnoses by radiologists by using the CNN model to assess its clinical utility.ResultsFor the CNN model, the AUC was 91% (95% confidence interval [CI]: 0.83–0.99) in the test set. The diagnostic accuracy of radiologists with the CNN model was significantly higher than that without the model (89 vs. 66%, P<0.01; 87 vs. 61%, P<0.01; 85 vs. 66%, P=0.03, in the train, validation, and test sets, respectively). In addition, while there was a slight increase in sensitivity, the specificity improved significantly by an average of 42% (the corresponding improvements in the three sets ranged from 43, 33, and 42% to 82, 78, and 84%, respectively; P<0.01 for all).ConclusionThe CNN model could be a valuable tool in non-invasively differentiating benign from malignant lesions manifesting as solid, indeterminate SPNs/SPMs on CT.

Clinical analysis for 12 patients with thoracic Castleman's disease.

To explore the clinical characteristics and differential diagnosis for patients with thoracic Castleman's disease, thus to improve doctor's cognition and therapeutic level for the disease. The clinical data of 12 patients with thoracic Castleman's disease were analyzed retrospectively, including clinical features, laboratory examination, imaging finding, pathological examination, treatment outcome, and prognosis. All 12 patients were diagnosed by mass or lymph code biopsy. Seven patients with unicentric Castleman's disease were asymptomatic or oligosymptomatic. Of them, the lung imaging features were mostly solitary and well-defined pulmonary hilar soft tissue mass and infrequently invasive mass. Pathologically, 7 patients were all hyaline vascular type. Six patients underwent surgery of complete mass resection, and 1 received chemotherapy because the nidus could not be resected completely. The prognosis of 7 patients was good. The clinical manifestations of 5 patients with multicentric Castleman's disease were diverse with negative prognosis. Their radiological features mainly showed multiple mediastinal/hilum lymph node enlargement, multiple serous cavity effusion, and hepatosplenomegaly, along with multifocal lymphadenopathy. Pathological features of 3 patients' mass were hyaline vascular type, 1 was plasma cell type, and 1 was mixed type. Three patients received comprehensive treatment on the basis of chemotherapy and another 2 patients did not receive any therapy. Unicentric Castleman's disease involving the chest is mainly manifested as mediastinal or hilar soft tissue mass with single clinical manifestation, while multicentric Castleman's disease involving the chest is mainly manifested as diffuse mediastinal/hilar lymph node enlargement, multifocal lymphadenopathy and multiple clinical manifestation. For patients with mediastinal/hilum mass or with multifocal lymphadenopathy, Castleman's disease should be considered the differential diagnosis. And early mass or lymph code biopsy is of great significance for diagnosis and treatment of Castleman's disease.

Manifestations of chest CT imaging in AIDS patients complicated with pulmonary cryptococcosis

Objective To analysis the manifestations of chest CT imaging in acquired immunodeficiency syndrome (AIDS) patients complicated with pulmonary cryptococcosis. Methods The clinical data of 72 AIDS patients complicated with pulmonary cryptococcosis were analyzed retrospectively. There were 3 cases (4.2%) diagnosed with pulmonary cryptococcosis by biopsy, including 1 case of pulmonary cryptococcosis and 2 cases of disseminated cryptococcosis; 69 cases (95.8%) with pulmonary manifestations and clinically diagnosed with pulmonary cryptococcosis, including 43 cases of cryptococcal meningitis and 26 cases of disseminated cryptococcosis. The imaging features of chest CT, in terms of the morphology, size, number, distribution, internal features and margins of the lesions were analyzed. Results The chest CT findings were solid nodules or mass in 49 cases (68.1%), patchy shadows in 40 cases (55.6%), cavitary nodules or mass in 10 cases (13.9%), mediastinal and hilar lymph node enlargement in 17 cases (23.6%) and pleural effusion in 10 cases (13.9%). Conclusion The chest CT findings of AIDS patients complicated with pulmonary cryptococcosis mainly are multiple solid nodules or masses, patchy shadows and solitary cavitary pulmonary nodules or mass. For early diagnosis and treatment, cryptococcus screening should be performed in HIV-infected patients with pulmonary nodules or mass on chest CT. Key words: Acquired immunodeficiency syndrome; Cryptococcosis; Tomography, X-ray computed

Lymphomatoid Granulomatosis: Rare Radiologic Presentation as a Solitary Pulmonary Mass

Background: Lymphomatoid granulomatosis (LYG) is a rare Epstein-Barr virus (EBV)-driven lymphoproliferative disease. LYG is characterized by a progressive clinical course, which virtually always involves the lungs. LYG characteristically presents as bilateral pulmonary nodules. Pathologically, it is characterized by an angiocentric and angiodestructive infiltration of atypical EBV-positive B-lymphocytes admixed with reactive T-lymphocytes. We report a case of pulmonary LYG that presented as a large mass with complete occlusion of the right main stem bronchus intermedius in an 81-year-old female. Case: An 81-year-old female presented with shortness of breath to the emergency department. Inpatient imaging revealed bulky mediastinal lymphadenopathy with a right lower lobe collapse, shift of the cardiomediastinal silhouette, and a large right upper lung mass. Endobronchial ultrasound-guided biopsy (EBUS) revealed complete occlusion of right mainstem bronchus due to the right upper lung mass growth into the bronchus intermedius. Histopathological examination demonstrated clusters of large atypical EBV-positive B cells interspersed in a minimally polymorphous lymphocytic background, consistent with lymphomatoid granulomatosis, grade 3/3. Patient was treated with immunochemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisone - CHOP) and Rituximab (anti-CD20 antibody). At the patient’s most recent follow-up, 6 months later, she was in a stable condition and her respiratory symptoms have improved. Conclusion: Lymphomatoid granulomatosis is a rare disease that should be considered in the differential diagnosis of a radiographic evaluation of a solitary pulmonary lung mass. Since the radiographic impression might favor carcinoma as the top differential diagnosis, biopsy of the lesion is paramount to ensure the correct diagnosis. Lymphomatoid granulomatosis is usually treated with an immunochemotherapy regimen with CHOP, and/or interferon, and Rituximab.

Electromagnetic Navigation Bronchoscopy: Where Are We Now? Five Years of a Single-Center Experience.

Electromagnetic navigation (ENB) is a guidance tool used in the diagnosis of solitary pulmonary nodules (SPNs) and masses. Its diagnostic yield is highly variable (38-71%) and a recent study has put in doubt the role of ENB in sampling SPNs in a real-life setting. The aim of this study is to describe the 5-year experience of our center with ENB, analyzing the population, possible confounding factors, and the diagnostic yield and accuracy of this technique. We conducted a retrospective observational study including all consecutive patients who underwent ENB for SPNs and masses from January 2011 to December 2015. We included 113 patients; 79% had SPNs, 21% masses. The majority were localized in the upper and middle lobes (80%) and 61% presented a bronchus sign. 54% of the patients had a previous negative fluoroscopy-guided bronchoscopy. ENB achieved the diagnosis in 78 patients (69%) with 64 malignant and 14 were benign lesions. The diagnostic yield and accuracy of ENB were respectively 0.69 and 0.76. The only factor influencing the ability to reach a diagnosis was the presence of bronchus sign (p = 0.002). No procedural complications were reported. ENB is a safe procedure with a similar diagnostic yield in the real-life and research setting. Bronchus sign is an important factor in determining the diagnostic yield. ENB efficacy can be maximized by expertise and by a careful selection of each case.

MRI for solitary pulmonary nodule and mass assessment: Current state of the art.

4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1437-1458.

Use of TBAg/PHA ratio in distinguishing tuberculoma from cancer in solitary pulmonary nodule or mass.

Differentiation of tuberculoma from cancer in solitary pulmonary nodule or mass still remains a major challenge in diagnostic laboratories. The objective of this study is to determine the performance of T-SPOT.TB assay in discriminating these 2 diseases. We prospectively enrolled 331 patients with a solitary pulmonary nodule or mass on computed tomography scans. Conventional tests and T-SPOT.TB assay were simultaneously performed in all participants. Our results showed that the performance of directly using T-SPOT.TB results in distinguishing tuberculoma from cancer in solitary pulmonary nodule or mass was not satisfactory because of moderate sensitivity and specificity. However, a further calculation of the ratio of TB-specific antigen (TBAg) to phytohemagglutinin (PHA) (TBAg/PHA ratio) of T-SPOT.TB assay may lead to improvement in distinguishing these 2 diseases. If using the threshold value of 0.236, the sensitivity and specificity of the TBAg/PHA ratio in distinguishing tuberculoma from cancer in solitary pulmonary nodule or mass were, respectively, 80.6% and 93.3%. The area under the curve (AUC) of the receiver operating characteristic curve was 0.921 (95% confidence interval, 0.875-0.967). Furthermore, the TBAg/PHA ratio may also be used to distinguish tuberculoma from other benign diseases (AUC: 0.909, sensitivity: 85.07%, specificity: 90%). Calculation of the TBAg/PHA ratio might provide a useful non-invasive tool for distinguishing tuberculoma from cancer in patients with a solitary pulmonary nodule or mass in TB-endemic countries.

Clinical analysis of non-AIDS patients pathologically diagnosed with pulmonary cryptococcosis.

Pulmonary cryptococcosis (PC) was not a rare infectious disease in non-AIDS patients. However, data on the immune status were lacking in southern China for comparative analysis of differences between immunocompromised and immunocompetent hosts. This study was to investigate the epidemiological, clinical, radiological, and treatment profiles for patients with PC. We performed a retrospective review of 88 patients diagnosed with tissue-confirmed PC who were not HIV-infected from 2003 to 2013. Of 88 patients, 35(39.7%) were immunocompromised host. Fever and CNS symptom were significantly common in immunocompromised patients compared to immunocompetent patients (P=0.019 and P=0.036, respectively). The most frequent radiologic abnormalities were solitary or multiple pulmonary nodules, and masses or consolidations, and most lesions were located in the peripheral lung field. Cavitations and halo sign were significantly frequent in immunocompromised patients than in immunocompetent patients (P<0.05). The most frequently applied and reliable diagnostic procedure was CT-guided percutaneous translung biopsy. Treatment included antifungal drug alone in 20 patients, surgery alone in 20 including 3 treated by VATS, surgery plus antifungal drugs in 20 patients. PC was not rare in immunocompetent host in southern China. Special differences remained in clinical manifestation and radiological findings of PC between immunocompromised and immunocompetent patients. Future work on the mechanisms of possible differences is required.

Dual-time-point 18F-FDG PET/CT in the diagnosis of solitary pulmonary lesions in a region with endemic granulomatous diseases.

Granulomatous diseases (GDs) can be metabolically active and indistinguishable from lung cancer on 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) imaging. Evaluation of solitary pulmonary lesions remains a diagnostic challenge in regions with endemic GD. This study sought to determine the efficacy of dual-time-point (DTP) 18F-FDG PET/computed tomography (CT) imaging in diagnosing solitary pulmonary lesions from such regions. A total of 50 patients with solitary pulmonary nodules or masses with confirmed histopathological diagnoses underwent DTP 18F-FDG PET/CT imaging at 1 and 3h after tracer injection. The maximum standardized uptake value (SUVmax) on early and delayed scans (SUV1h and SUV3h, respectively) and retention index (RI) were calculated for each pulmonary lesion. Receiver operating characteristic analysis was performed to evaluate the discriminating validity of the parameters. There were 37 malignant and 13 benign solitary pulmonary lesions. Eight of the 13 (62%) benign lesions were GDs. The sensitivity/specificity/accuracy of SUV1h, SUV3h and RI were 84/69/80%, 84/85/84%, and 81/54/74%, respectively. SUV3h had the best diagnostic performance, especially regarding specificity. The values of SUV1h and SUV3h were significantly different between malignant lesions and GD, while the RI values of malignant lesions and GD were both high (18.6±19.5 and 18.7±15.3%, respectively; P=not significant). SUV3h appeared to improve the diagnostic specificity of 18F-FDG PET/CT in evaluating solitary pulmonary lesions from regions with endemic GD.

The development of large-cell carcinoma in the wall of a giant bulla complicated by hemorrhage.

There were a few reports of patients with lung cancer developing at the wall of giant bullae complicated with hemorrhage. A 40-year-old male with complaints of hemoptysis was referred to our hospital, and a solitary pulmonary mass was pointed out on his chest roentgenogram. Computed tomography (CT) demonstrated a well-circumscribed solid mass measuring 7.0 × 6.5 × 6.0 cm in the right upper lobe of the lung. At the chest CT 1 year before, only a giant bulla without mass was found. From the interval change of CT findings with his clinical course, the mass was suspected as acute hemorrhage in the giant bulla. A right upper lobectomy of the lung was performed to control his hemoptysis. The surgical specimen showed the giant bulla filled with blood clot, and a partial wall of the bulla was irregularly thickened. Pathological examination revealed that the thickened wall was composed of large-cell carcinoma. In patients with bullous diseases complicated with hemorrhage, we should be aware of a possibility of developing lung cancer in the bullae.

Effectiveness of the addition of the brain region to the FDG-PET/CT imaging area in patients with suspected or diagnosed lung cancer.

We aimed to evaluate the effectiveness of the brain region imaging in FDG-PET/CT scanning of patients with suspected or diagnosed lung cancer. We performed the study retrospectively on the medical charts of 427 patients. We divided the FDG-PET/CT field of view (FOV) into four major imaging regions: brain, head-neck, abdomen and pelvis. Metastatic findings on these regions were checked and determined the potential of these findings to affect the chemotherapy or radiotherapy protocol or surgical management. If metastatic findings had a potential to modify these parameters, we named this situation as "clinical contribution". Considering the number of bed positions of these regions, we calculated the clinical contribution of each region and named as "effective clinical contribution". Then, we calculated the metastatic findings, clinical contribution, and effective clinical contribution ratios. We found different brain metastasis ratios for lung cancer, solitary pulmonary mass (SPM), and solitary pulmonary nodule (SPN) groups (8.7, 2.8 and 0.9%, respectively). In addition, the clinical contribution and effective clinical contribution ratios in the brain region for these three groups were 6.4, 2.8, 0.0 and 6.4, 2.8, 0.0%, respectively. The highest metastatic findings (30.6%) and clinical contribution (9.8%) ratios were found in the abdomen region of the lung cancer group. However, the highest effective clinical contribution ratio (6.8%) was found in the brain region within the same group. The addition of the brain region to the limited whole-body FOV in FDG-PET/CT scanning seems to be effective in the lung cancer and SPM groups, but not in the SPN group.

The diagnostic accuracy of integrated positron emission tomography/computed tomography in the evaluation of pulmonary mass lesions in a tuberculosis-endemic area.

Integrated positron emission tomography/computed tomography (PET-CT) is a well-validated modality for assessing pulmonary mass lesions and specifically for estimating risk of malignancy. Tuberculosis (TB) is known to cause false-positive PET-CT findings. To investigate the utility of PET-CT in the evaluation of pulmonary mass lesions and nodules in a high TB prevalence setting. All patients referred for the evaluation of a solitary pulmonary nodule or mass and who underwent PET-CT scanning over a 3-year period were included. The PET-CT findings, including maximum standardised uptake value (SUVmax), were compared with the gold standard (tissue or microbiological diagnosis). The sensitivity, specificity, positive and negative predictive values and diagnostic accuracy for malignant disease were calculated according to the SUVmax cut-off of 2.5 and a proposed cut-off obtained from a receiver operating characteristic (ROC) curve. Forty-nine patients (mean (standard deviation) age 60.1 (10.2) years; 29 males) were included, of whom 30 had malignancy. Using an SUVmax cut-off of 2.5, PET-CT had a sensitivity, specificity, positive and negative predictive value and diagnostic accuracy for malignancy of 93.3%, 36.8%, 70.0%, 77.8% and 71.4%, respectively. After a ROC curve analysis, a suggested SUVmax cut-off of 5.0 improved the specificity to 78.9% and the diagnostic accuracy to 86.7%, with a small reduction in sensitivity to 90.0%. The diagnostic accuracy of PET-CT in the evaluation of pulmonary mass lesions using the conventional SUVmax cut-off of 2.5 was reduced in a TB-endemic area. An SUVmax cut-off of 5.0 has a higher specificity and diagnostic accuracy for malignancy, with a comparable sensitivity.

Diffusion Weighted Magnetic Resonance Imaging for the Characterization of Solitary Pulmonary Lesions.

We evaluated the differential diagnosis of solitary pulmonary lesions on magnetic resonance imaging. To investigate the value of diffusion weighted imaging on the differential diagnosis of solitary pulmonary lesions. Randomized prospective study. This prospective study included 48 solitary pulmonary nodules and masses (18 benign, 30 malignant). Single shot echo planar spin echo diffusion weighted imaging (DWI) was performed with two b factors (0 and 1000 s/mm(2)). Apparent diffusion coefficients (ADCs) were calculated. On diffusion weighted (DW) trace images, the signal intensities (SI) of the lesions were visually compared to the SI of the thoracic spinal cord using a 5-point scale: 1: hypointense, 2: moderately hypointense, 3: isointense, 4: moderately hyperintense, 5: significantly hyperintense. For the quantitative evaluation, the lesion to thoracic spinal signal intensity ratios and the ADCs of the lesions were compared between groups. On visual evaluation, taking the density of the spinal cord as a reference, most benign lesions were found to be hypointense, while most of the malignant lesions were evaluated as hyperintense on DWI with a b factor of 1000 s/mm(2). In contrast, on T2 weighted images, it was seen that the distinction of malignant lesions from benign lesions was not statistically significant. The ADCs of the malignant lesions were significantly lower than those of benign lesions (mean ADC was 2.02×10(-3) mm(2)/s for malignant lesions, and 1.195×10(-3)±0.3 mm(2)/s for benign lesions). Setting the cut-off value at 1.5×10(-3), ADC had a sensitivity of 86.7% and a specificity of 88.9% for the differentiation of benign lesions from malignant lesions. DWI may aid in the differential diagnosis of solitary pulmonary lesions. (ClinicalTrials.gov Identifier: NCT02482181).

A Case of Solitary Pulmonary Mass with Air-Bubble Sign: What Is Your Diagnosis?

• Available online at www.eurasianjpulmonol.com A 58-year-old male patient was admitted to our clinic with complaints of productive cough and weight loss (6 kg) having begun with flu-like symptoms 15 days ago. His medical history included the use of acetylsalicylic acid after a cerebrovascular event from 9 years ago. The patient, who worked as a car mechanic, had 40 packs-year of smoking history. In the physical examination, his vital findings and oxygen saturation were within normal reference intervals, and no abnormality was observed, except limping in his right foot. Pulmonary function tests revealed mild obstructive dysfunction. The laboratory test value of C-reactive protein was 7.3, and the values of complete blood count and biochemistry were within normal intervals. The PPD test result was 10 mm.

The role of FDG-PET/CT in detecting unsuspected and unknown distant metastasis in the initial staging of NSCLC.

Our purpose in this retrospective study was to determine the ratio of unexpected [metastases within the coverage area of thorax computed tomography (CT)] and unknown (metastases out of the coverage area of thorax CT) metastases by positron emission tomography/CT (PET/CT) in patients with newly diagnosed non-small cell lung cancer (NSCLC) who had no defined metastatic lesion, and to investigate the contribution of fludeoxyglucose (FDG)-PET/CT in metastasis staging. A total of 567 patients (489 males and 78 females, mean age 60.9 ± 10.7 years) were enrolled in this study. Among the 567 patients, a total of 156 patients who underwent PET/CT for metabolic characterization (group 1) and had solitary pulmonary nodules (group la, n = 39) or solitary pulmonary masses (group lb, n = 117) and the remaining 411 patients (group 2) with NSCLC who had PET/CT performed for staging formed the basis of this study In group 1, 5/39 (12.8%) patients with a solitary pulmonary nodule and 29/117 (24.8%) patients with a solitary pulmonary mass had distant metastases. In group 2, 129 patients of 411 (31.4%) had distant metastasis. FDG-PET/CT is proven to be an effective method in detection of unsuspected-unknown metastasis, either in patients with solitary pulmonary lesion or in the initial staging of patients with NSCLC.

Clinical Characteristics of Patients With Solitary Pulmonary Mass After Radical Treatment for Primary Cancers: Pulmonary Metastasis or Second Primary Lung Cancer?

We identified clinical characteristics of 30 pulmonary metastasis (PM) patients and 29 second primary lung cancer (SPLC) patients with feature of solitary pulmonary mass (SPM) after radical treatment of prior cancers. 6.7% and 44.8% patients presented with centrally located SPM and the median event-free durations were 33 and 72 months in PM and SPLC groups, respectively. PM was more likely to be found in prior cancers with stage III. In conclusion, the location of SPM, the event-free duration and the prior tumor staging were important features for differentiating SPLC from PM among patients with SPM after prior cancers.

Primary pulmonary solitary fibrous tumour with brain metastases

Solitary fibrous tumour (SFT) is a mesenchymal neoplasm of subendothelial origin that can be found in all anatomical locations, but rarely in the lungs. A 71-year old female was referred to our hospital because of the increase in size of a solitary pulmonary mass. Chest contrast-enhanced dynamic computed tomography showed a well-circumscribed lobulated mass measuring 3.1×1.6 cm in the posterior segment of the right upper lobe of the lung. Positron emission tomography with 18F-fluorodeoxyglucose (FDG) demonstrated that the mass had high FDG uptake. A right upper lobectomy of the lung and mediastinal lymphadenectomy were performed. The tumour was pathologically diagnosed as an SFT. Seven months later, the patient was found to have brain metastases of the tumour, which led to dizziness. A craniotomy and successive radiosurgery with a gamma knife were performed for the metastatic tumours. She is still alive without evidence of disease 12 months after the treatment of the metastases. Pulmonary SFT seldom behaves aggressively, and only two previous cases of primary pulmonary SFT with brain metastases have been reported. Local therapy including surgery and radiotherapy against metastases from SFT could help improve the survival of such patients.