Pathological diagnosis and immunohistochemical analysis of minute pulmonary meningothelial-like nodules: A case report

BACKGROUND

Minute Pulmonary Meningothelial-like Nodules (MPMNs) are rare benign pulmonary nodules, which are more common in elderly women and have a higher detection rate in lung tissues of patients with lung malignant diseases. Its origin is not yet clear. At present, there are few reports on the diagnostic methods such as imaging and pathological manifestations of MPMNs. This article reports a 70-year-old female patient with pulmonary adenocarcinoma combined with MPMNs and reviews of the relevant literature.

CASE SUMMARY

A 70-year-old women was admitted to our institution with feeling sour in her back and occasional cough for more than 2 mo. Computerized electronic scanning scan and 3D reconstruction images in our institution showed there were multiple ground-glass nodules in both of her two lungs. The biggest one was in the apicoposterior segment of left upper lobe, about 2.5 mm × 9 mm in size. We performed thoracoscopic resection of the left upper lung apicoposterior segment of the patient, and the final pathological report was minimally invasive adenocarcinoma. Re-examination of high resolution computed tomography 21 mo after surgery showed multiple ground-glass nodules in both lungs, and a new ground-glass nodule was found in the superior segment of the right lower lobe. We took pathological biopsy of the right upper lung and right lower lung nodules for the patient under thoracoscopy. The histomorphology of the right lower lobe nodule showed multiple lesions in the lung tissue, and the small foci in the alveolar septum were distributed in mild form of the aggregation of short spindle cells. The immunohistochemistry showed that the lesion was epithelial membrane antigen (EMA) (+), somatostatin receptor 2a (SSTR2a) (+), S-100 (-), chromogranin A (-), Syn (-), cytokeratin (-) and HMB-45 (-). The final diagnosis was minimally invasive adenocarcinoma, accompanied by MPMNs. We recommend that patients continue to receive treatment after surgery and to do regular follow-up observations.

CONCLUSION

The imaging manifestations of MPMNs are atypical, histomorphology and immunohistochemistry can assist in its diagnosis. This article reviews the relevant literature of MPMNs immunohistochemistry and shows that MPMNs are positive for EMA, SSTR2a, and progesterone receptor.

Trends in the incidence of pulmonary nodules in chest computed tomography: 10-year results from two Dutch hospitals

OBJECTIVE

To study trends in the incidence of reported pulmonary nodules and stage I lung cancer in chest CT.

METHODS

We analyzed the trends in the incidence of detected pulmonary nodules and stage I lung cancer in chest CT scans in the period between 2008 and 2019. Imaging metadata and radiology reports from all chest CT studies were collected from two large Dutch hospitals. A natural language processing algorithm was developed to identify studies with any reported pulmonary nodule.

RESULTS

Between 2008 and 2019, a total of 74,803 patients underwent 166,688 chest CT examinations at both hospitals combined. During this period, the annual number of chest CT scans increased from 9955 scans in 6845 patients in 2008 to 20,476 scans in 13,286 patients in 2019. The proportion of patients in whom nodules (old or new) were reported increased from 38% (2595/6845) in 2008 to 50% (6654/13,286) in 2019. The proportion of patients in whom significant new nodules (≥ 5 mm) were reported increased from 9% (608/6954) in 2010 to 17% (1660/9883) in 2017. The number of patients with new nodules and corresponding stage I lung cancer diagnosis tripled and their proportion doubled, from 0.4% (26/6954) in 2010 to 0.8% (78/9883) in 2017.

CONCLUSION

The identification of incidental pulmonary nodules in chest CT has steadily increased over the past decade and has been accompanied by more stage I lung cancer diagnoses.

CLINICAL RELEVANCE STATEMENT

These findings stress the importance of identifying and efficiently managing incidental pulmonary nodules in routine clinical practice.

KEY POINTS

• The number of patients who underwent chest CT examinations substantially increased over the past decade, as did the number of patients in whom pulmonary nodules were identified. • The increased use of chest CT and more frequently identified pulmonary nodules were associated with more stage I lung cancer diagnoses.

Robustness of pulmonary nodule radiomic features on computed tomography as a function of varying radiation dose levels-a multi-dose in vivo patient study

OBJECTIVE

Analysis of textural features of pulmonary nodules in chest CT, also known as radiomics, has several potential clinical applications, such as diagnosis, prognostication, and treatment response monitoring. For clinical use, it is essential that these features provide robust measurements. Studies with phantoms and simulated lower dose levels have demonstrated that radiomic features can vary with different radiation dose levels. This study presents an in vivo stability analysis of radiomic features for pulmonary nodules against varying radiation dose levels.

METHODS

Nineteen patients with a total of thirty-five pulmonary nodules underwent four chest CT scans at different radiation dose levels (60, 33, 24, and 15 mAs) in a single session. The nodules were manually delineated. To assess the robustness of features, we calculated the intra-class correlation coefficient (ICC). To visualize the effect of milliampere-second variation on groups of features, a linear model was fitted to each feature. We calculated bias and calculated the R2 value as a measure of goodness of fit.

RESULTS

A small minority of 15/100 (15%) radiomic features were considered stable (ICC > 0.9). Bias increased and R2 decreased at lower dose, but shape features seemed to be more robust to milliampere-second variations than other feature classes.

CONCLUSION

A large majority of pulmonary nodule radiomic features were not inherently robust to radiation dose level variations. For a subset of features, it was possible to correct this variability by a simple linear model. However, the correction became increasingly less accurate at lower radiation dose levels.

CLINICAL RELEVANCE STATEMENT

Radiomic features provide a quantitative description of a tumor based on medical imaging such as computed tomography (CT). These features are potentially useful in several clinical tasks such as diagnosis, prognosis prediction, treatment effect monitoring, and treatment effect estimation.

KEY POINTS

• The vast majority of commonly used radiomic features are strongly influenced by variations in radiation dose level. • A small minority of radiomic features, notably the shape feature class, are robust against dose-level variations according to ICC calculations. • A large subset of radiomic features can be corrected by a linear model taking into account only the radiation dose level.

[Clinical diagnosis and treatment of multiple pulmonary nodules]

CT screening has markedly reduced the lung cancer mortality in high-risk population and increased the detection of early-stage pulmonary neoplasms, including multiple pulmonary nodules, especially those with a ground-glass appearance on CT. Multiple primary lung cancer (MPLC) constitutes a specific subtype of lung cancer with indolent biological behaviors, which is predominantly early-stage adenocarcinoma. Although MPLC progresses slowly with rare lymphatic metastasis, existence of synchronous lesions and distributed location of these nodules still pose difficulty for the management of such patients. One single operation is usually insufficient to eradicate all neoplastic lesions, whereas repeated surgical procedures bring about another dilemma: whether clinical benefits of surgical treatment outweigh loss of pulmonary function following multiple operations. Therefore, despite the anxiety for treatment among MPLC patients, whether and how to treat the patient should be assessed meticulously. Currently there is a heated discussion upon the timing of clinical intervention, operation mode and the application of local therapy in MPLC. Based on clinical experience of our multiple disciplinary team, we have summarized and commented on the evaluation, surgical treatment, non-surgical local treatment, targeted therapy and immunotherapy of MPLC in this article to provide further insight into this field.

A case of idiopathic multicentric Castleman disease with pulmonary hyalinizing granuloma-like multiple pulmonary nodules

A 41-year-old man presented with chronic cough and chest pain. Laboratory tests revealed anemia, inflammation, hypoalbuminemia, polyclonal hypergammaglobulinemia, and elevated interleukin-6 levels. Computed tomography revealed diffuse bilateral pulmonary nodules and multicentric lymphadenopathy. Histopathology of the pulmonary nodule resembled pulmonary hyalinizing granuloma (PHG), whereas lymph node histopathology was consistent with idiopathic multicentric Castleman disease (iMCD). The patient was diagnosed with iMCD involving PHG-like pulmonary nodules. Little is known about the association between these two diseases, and the present case provides insights regarding the relationship between PHG and iMCD.

Case report: identification of EGFR R776H and FANCE R381H germline mutations in a patient with multiple pulmonary nodules

Pulmonary nodules evaluation is clinically crucial because they may be the early predictors of lung cancer. Except for CT screening and serum tumor biomarkers testing, genetic alteration analysis by next-generation sequencing (NGS) technology can also help to find cancer earlier. In this study, we report a case of multiple pulmonary nodules patient with EGFR R776H and FANCE R381H germline mutations. Her father, paternal aunt, and elder uncle harbored either one or both two mutations and were found with multiple pulmonary ground-glass or sub-solid nodules. Her 7-year-old daughter also inherited the same two mutations.

Newly diagnosed metastatic pulmonary calcification in a kidney transplantation recipient: a case report

Metastatic pulmonary calcification (MPC) is defined as calcium deposition in lung tissues. It is commonly seen in end-stage renal disease patients. However, MPC occurring in kidney transplant recipients (KTRs) is rare. We report a case of MPC in a 55-year-old female patient after successful kidney transplantation (KT). One year after KT, bisphosphonate and vitamin D were prescribed for osteoporosis. Then, 4.5 years after KT, we incidentally found multiple nodular lesions on chest X-ray (CXR) without any symptoms. Chest computed tomography showed multiple high-density nodules. A bone scan confirmed MPC in the right middle lobe and right lower lobe. A retrospective review of pretransplant blood chemistry revealed the following: serum calcium level, 11.2 mg/dL; phosphorus level, 3.2 mg/dL; intact parathyroid hormone level, lower than 2.5 pg/mL; and 24-hour urine calcium level, within normal limits (WNL). After KT, all of these parameters remained WNL. Therefore, hidden adynamic bone disease might have been aggravated by bisphosphonate and vitamin D supplementation, causing MPC. Both were discontinued. She was monitored by routine CXR, and MPC did not progress. Since MPC is commonly asymptomatic and difficult to diagnose in KTRs, caution is required when administering such medications. Patient should be followed up with routine CXR.

Clinical impact of a deep learning system for automated detection of missed pulmonary nodules on routine body computed tomography including the chest region

OBJECTIVES

To evaluate the clinical impact of a deep learning system (DLS) for automated detection of pulmonary nodules on computed tomography (CT) images as a second reader.

METHODS

This single-centre retrospective study screened 21,150 consecutive body CT studies from September 2018 to February 2019. Pulmonary nodules detected by the DLS on axial CT images but not mentioned in initial radiology reports were flagged. Flagged images were scored by four board-certificated radiologists each with at least 5 years of experience. Nodules with scores of 2 (understandable miss) or 3 (should not be missed) were then categorised as unlikely to be clinically significant (2a or 3a) or likely to be clinically significant (2b or 3b) according to the 2017 Fleischner guidelines for pulmonary nodules. The miss rate was defined as the total number of studies receiving scores of 2 or 3 divided by total screened studies.

RESULTS

Among 172 nodules flagged by the DLS, 60 (35%) missed nodules were confirmed by the radiologists. The nodules were further categorised as 2a, 2b, 3a, and 3b in 24, 14, 10, and 12 studies, respectively, with an overall positive predictive value of 35%. Missed pulmonary nodules were identified in 0.3% of all CT images, and one-third of these lesions were considered clinically significant.

CONCLUSIONS

Use of DLS-assisted automated detection as a second reader can identify missed pulmonary nodules, some of which may be clinically significant.

CLINICAL RELEVANCE/APPLICATION

Use of DLS to help radiologists detect pulmonary lesions may improve patient care.

KEY POINTS

• DLS-assisted automated detection as a second reader is feasible in a large consecutive cohort. • Performance of combined radiologists and DLS was better than DLS or radiologists alone. • Pulmonary nodules were missed more frequently in abdomino-pelvis CT than the thoracic CT.

[Application of CT-guided Localization with Medical Glue for Single and Two or More Small Pulmonary Nodules before Video-assisted Thoracic Surgery]

BACKGROUND

The localization of pulmonary nodules is related to whether the lesions can be found and removed accurately and quickly. It is an important link for the success of minimally invasive video-assisted thoracic surgery (VATS). This study investigated the feasibility of medical glue localization under VATS video-assisted thoracoscopic computed tomography (CT) guidance for single pulmonary nodule and more than two pulmonary nodules, and compared with the accuracy and safety of single nodule localization.

METHODS

A retrospective analysis of the clinical data of patients who underwent unilateral CT-guided medical glue localization before VATS from November 2018 to March 2021 were performed, the patients was divided into multiple pulmonary nodules group (localized nodules ≥2) and single pulmonary nodule group according to the number of localized nodules. The localization time, success rate and complication rate of the two groups were compared.

RESULTS

There were 126 nodules in the two groups, including 62 in single pulmonary nodule group and 64 in multiple pulmonary nodules group. The average single nodule localization time was (13.23±4.5) min in single pulmonary nodule group and (10.52±2.8) min in multiple pulmonary nodules group, the difference between the two groups is statistically significant (P<0.05). The localization success rate of single pulmonary nodule group and multiple pulmonary nodules group were 100% and 98.4% separately, the difference between the two groups was not statistically significant (P>0.05). All VATS were successfully completed after localization. The incidence of pneumothorax was higher in multiple pulmonary nodules group than in single pulmonary nodule group (P=0.07).

CONCLUSIONS

Compared with localization of single lung nodule, unilateral CT-guided medical glue localization for multiple pulmonary nodules before VATS is also feasible and accuracy, it is worthy of clinical application. But the higher rate of pneumothorax should be paid attention to.

A radiomics approach for lung nodule detection in thoracic CT images based on the dynamic patterns of morphological variation

OBJECTIVES

To propose and evaluate a set of radiomic features, called morphological dynamics features, for pulmonary nodule detection, which were rooted in the dynamic patterns of morphological variation and needless precise lesion segmentation.

MATERIALS AND METHODS

Two datasets were involved, namely, university hospital (UH) and LIDC datasets, comprising 72 CT scans (360 nodules) and 888 CT scans (2230 nodules), respectively. Each nodule was annotated by multiple radiologists. Denoted the category of nodules identified by at least k radiologists as ALk. A nodule detection algorithm, called CAD-MD algorithm, was proposed based on the morphological dynamics radiomic features, characterizing a lesion by ten sets of the same features with different values extracted from ten different thresholding results. Each nodule candidate was classified by a two-level classifier, including ten decision trees and a random forest, respectively. The CAD-MD algorithm was compared with a deep learning approach, the N-Net, using the UH dataset.

RESULTS

On the AL1 and AL2 of the UH dataset, the AUC of the AFROC curves were 0.777 and 0.851 for the CAD-MD algorithm and 0.478 and 0.472 for the N-Net, respectively. The CAD-MD algorithm achieved the sensitivities of 84.4% and 91.4% with 2.98 and 3.69 FPs/scan and the N-Net 74.4% and 80.7% with 3.90 and 4.49 FPs/scan, respectively. On the LIDC dataset, the CAD-MD algorithm attained the sensitivities of 87.6%, 89.2%, 92.2%, and 95.0% with 4 FPs/scan for AL1-AL4, respectively.

CONCLUSION

The morphological dynamics radiomic features might serve as an effective set of radiomic features for lung nodule detection.

KEY POINTS

• Texture features varied with such CT system settings as reconstruction kernels of CT images, CT scanner models, and parameter settings, and so on. • Shape and first-order statistics were shown to be the most robust features against variation in CT imaging parameters. • The morphological dynamics radiomic features, which mainly characterized the dynamic patterns of morphological variation, were shown to be effective for lung nodule detection.

Defining growth in small pulmonary nodules using volumetry: results from a "coffee-break" CT study and implications for current nodule management guidelines

Objectives

An increase in lung nodule volume on serial CT may represent true growth or measurement variation. In nodule guidelines, a 25% increase in nodule volume is frequently used to determine that growth has occurred; this is based on previous same-day, test–retest (coffee-break) studies examining metastatic nodules. Whether results from prior studies apply to small non-metastatic nodules is unknown. This study aimed to establish the interscan variability in the volumetric measurements of small-sized non-metastatic nodules.

Methods

Institutional review board approval was obtained for this study. Between March 2019 and January 2021, 45 adults (25 males; mean age 65 years, range 37–84 years) with previously identified pulmonary nodules (30–150 mm³) requiring surveillance, without a known primary tumour, underwent two same-day CT scans. Non-calcified solid nodules were measured using commercial volumetry software, and interscan variability of volume measurements was assessed using a Bland–Altman method and limits of agreement.

Results

One hundred nodules (range 28–170 mm³; mean 81.1 mm³) were analysed. The lower and upper limits of agreement for the absolute volume difference between the two scans were − 14.2 mm³ and 12.0 mm³ respectively (mean difference 1.09 mm³, range − 33–12 mm³). The lower and upper limits of agreement for relative volume difference were − 16.4% and 14.6% respectively (mean difference 0.90%, range − 24.1–32.8%).

Conclusions

The interscan volume variability in this cohort of small non-metastatic nodules was smaller than that in previous studies involving lung metastases of varying sizes. An increase of 15% in nodule volume on sequential CT may represent true growth, and closer surveillance of these nodules may be warranted.

Key Points

• In current pulmonary nodule management guidelines, a threshold of 25% increase in volume is required to determine that true growth of a pulmonary nodule has occurred.

• This test–retest (coffee break) study has demonstrated that a smaller threshold of 15% increase in volume may represent true growth in small non-metastatic nodules.

• Closer surveillance of some small nodules growing 15–25% over a short interval may be appropriate.

Impact of Vessel Suppressed-CT on Diagnostic Accuracy in Detection of Pulmonary Metastasis and Reading Time

RATIONALE AND OBJECTIVES

To assess if vessel suppression (VS) improves nodule detection rate, interreader agreement, and reduces reading time in oncologic chest computed tomography (CT).

MATERIAL AND METHODS

One-hundred consecutive oncologic patients (65 male; median age 60y) who underwent contrast-enhanced chest CT were retrospectively included. For all exams, additional VS series (ClearRead CT, Riverrain Technologies, Miamisburg) were reconstructed. Two groups of three radiologists each with matched experience were defined. Each group evaluated the SD-CT as well as VS-CT. Each reader marked the presence, size, and position of pulmonary nodules and documented reading time. In addition, for the VS-CT the presence of false positive nodules had to be stated. Cohen's Kappa (k) was used to calculate the interreader-agreement between groups. Reading time was compared using paired t test.

RESULTS

Nodule detection rate was significantly higher in VS-CT compared to the SD-CT (+21%; p <0.001). Interreader-agreement was higher in the VS-CT (k = 0.431, moderate agreement) compared to SD-CT (k = 0.209, fair agreement). Almost all VS-CT series had false positive findings (97-99 out of 100). Average reading time was significantly shorter in the VS-CT compared to the SD-CT (154 ± 134vs. 194 ± 126; 21%, p<0.001).

CONCLUSIONS

Vessel suppression increases nodule detection rate, improves interreader agreement, and reduces reading time in chest CT of oncologic patients. Due to false positive results a consensus reading with the SD-CT is essential.

Computed tomography-guided cyanoacrylate injection for localization of multiple ipsilateral lung nodules

OBJECTIVES

To retrospectively assess the clinical effectiveness of CT-guided cyanoacrylate localization for multiple ipsilateral small pulmonary nodules (SPNs) and to determine the independent predictors for pneumothorax.

METHODS

In total, 81 patients with 169 lesions undergoing CT-guided cyanoacrylate localization for multiple ipsilateral SPNs between September 2016 and July 2020 were enrolled (group M). Another 284 patients who received single SPN localization during the same period served as the control group (group S). Propensity score analysis was performed to minimize selection bias. Possible independent predictors for pneumothorax were evaluated using multivariate logistic regression analysis.

RESULTS

Multiple ipsilateral SPN localization was successfully performed in all 81 patients. The incidences of successful targeting during localization and surgery were 100% and 98.8%, respectively. Seventy-seven patients (95.1%) underwent the procedure on the day before the surgery. Propensity matching created 81 pairs of patients. There were no significant differences in the incidence of successful targeting during localization and surgery, localization-related pain score, and additional morphine use between the two groups. However, group M was associated with a significant longer localization procedural time (p < 0.001) and a higher incidence of pneumothorax (p < 0.001). In multivariate analysis, position change was significantly associated with a sevenfold increase in the risk for pneumothorax (p = 0.001).

CONCLUSIONS

CT-guided cyanoacrylate injection for multiple ipsilateral SPN localization was safe and reliable, and allowed a flexible surgical schedule, despite a lengthy procedure and an increased incidence of pneumothorax. Avoiding position change may help to reduce the occurrence of pneumothorax.

KEY POINTS

• Compared to single SPN localization, multiple ipsilateral SPN localization using cyanoacrylate injection achieved comparable safety, reliability, and comfort. • CT-guided cyanoacrylate localization for multiple ipsilateral SPNs allowed a flexible surgical schedule. • Position change was the only independent risk factor for pneumothorax during the multiple ipsilateral SPN localization.

Next-generation sequencing facilitates differentiating between multiple primary lung cancer and intrapulmonary metastasis: a case series

Background

In lung cancer management, differential diagnosis between multiple primary lung cancer (MPLC) and intrapulmonary metastasis (IMP) is a critical point that is of direct therapeutic and clinical importance. However, this process often suffers from absence of a gold standard, resulting in equivocal cases. Herein, we present a series of three cases, in which genomic alteration patterns revealed by next-generation sequencing (NGS) facilitated the differential diagnosis between MPLC and IMP.

Case presentation

Case 1 was a 57-year-old female with two separate lesions in the upper lobe and the lower lobe of left lung, which were both histopathologically determined as T2aN0M0 adenocarcinomas. NGS identified an EGFR L858R in one lesion and an EGFR 20 exon insertion in the other one, suggestive of double primary malignancies. The patient underwent wedge resections and received an adjuvant treatment of icotinib and chemotherapy. She had a disease-free survival (DFS) of 19 months and counting. Case 2 was a 55-year-old female with multiple small lesions in both lungs. Histopathological examinations of resected lesions from right upper lobe revealed three subtypes: atypical adenomatous hyperplasia of alveolar epithelium, adenocarcinomas in situ and minimally invasive adenocarcinoma. NGS identified two different BRAF driver mutations G466E and V600_K601delinsE in two lesions of adenocarcinoma in situ, and a BRAF K601E in a lesion of minimally invasive adenocarcinoma. Case 3, a 68-year-old male, had the right upper lobe lesion histophathologically classified as a stage T3NxM0 mixed adenoneuroendocrine carcinoma and the left upper lobe lesion as a stage T1aN0M0 adenocarcinoma. NGS performed with different loci of surgical tissues revealed a rare sensitizing EGFR mutation G719A shared by the right upper lobe lesion and lymph node, and two EGFR mutations L861Q and G719S in left upper lobe lesion. The patient received icotinib treatment postoperatively and achieved a stable disease with a progression-free survival of 5 months.

Conclusion

Our cases provide evidence for utility of NGS in facilitating diagnosis and treatment decisions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-021-01083-6.

Simultaneous preoperative computed tomography-guided microcoil localizations of multiple pulmonary nodules

OBJECTIVES

To evaluate retrospectively the feasibility and safety of simultaneous multiple microcoil localizations of multiple pulmonary nodules prior to video-assisted thoracoscopic surgery (VATS).

METHODS

This retrospective cohort study enrolled 288 consecutive patients, who underwent computed tomography (CT)-guided microcoil localization and subsequent VATS at our academic hospital between July 2017 and June 2018. Of these patients, 36 with 79 pulmonary nodules undergoing simultaneous multiple microcoil localizations in the ipsilateral lung were designated the multiple localization group; the remaining 252 with 252 pulmonary nodules undergoing single microcoil localization were designated the single localization group. The main outcomes were the technical success and complication rates of the localization procedures. The Student t test and Mann-Whitney U test were used for continuous variables. The chi-squared test and logistic regression analysis were used to assess dichotomous variables.

RESULTS

The localization technical success rates of the multiple and single localization groups were 96.2% (76/79) and 98.0% (247/252), respectively (p = 0.326). The rate of any complication (pneumothorax or pulmonary hemorrhage) was significantly higher in the multiple localization than in the single localization group (55.6% vs 21.8%, respectively; p < 0.001). The incidence of pneumothorax was significantly higher in the multiple localization than in the single localization group (p < 0.001). The difference between the incidence of pulmonary hemorrhage in the 2 groups was not significant (p = 0.385).

CONCLUSIONS

Although preoperative CT-guided simultaneous microcoil localizations of multiple pulmonary nodules produced a significantly higher incidence of pneumothorax, the localizations were clinically feasible and safe.

KEY POINTS

• Simultaneous preoperative CT-guided microcoil localizations of multiple pulmonary nodules are clinically feasible and safe. • Simultaneous microcoil localizations of multiple pulmonary nodules produced a significantly higher incidence of pneumothorax.

Determining the invasiveness of ground-glass nodules using a 3D multi-task network

OBJECTIVES

The aim of this study was to determine the invasiveness of ground-glass nodules (GGNs) using a 3D multi-task deep learning network.

METHODS

We propose a novel architecture based on 3D multi-task learning to determine the invasiveness of GGNs. In total, 770 patients with 909 GGNs who underwent lung CT scans were enrolled. The patients were divided into the training (n = 626) and test sets (n = 144). In the test set, invasiveness was classified using deep learning into three categories: atypical adenomatous hyperplasia (AAH) and adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and invasive pulmonary adenocarcinoma (IA). Furthermore, binary classifications (AAH/AIS/MIA vs. IA) were made by two thoracic radiologists and compared with the deep learning results.

RESULTS

In the three-category classification task, the sensitivity, specificity, and accuracy were 65.41%, 82.21%, and 64.9%, respectively. In the binary classification task, the sensitivity, specificity, accuracy, and area under the ROC curve (AUC) values were 69.57%, 95.24%, 87.42%, and 0.89, respectively. In the visual assessment of GGN invasiveness of binary classification by the two thoracic radiologists, the sensitivity, specificity, and accuracy of the senior and junior radiologists were 58.93%, 90.51%, and 81.35% and 76.79%, 55.47%, and 61.66%, respectively.

CONCLUSIONS

The proposed multi-task deep learning model achieved good classification results in determining the invasiveness of GGNs. This model may help to select patients with invasive lesions who need surgery and the proper surgical methods.

KEY POINTS

• The proposed multi-task model has achieved good classification results for the invasiveness of GGNs. • The proposed network includes a classification and segmentation branch to learn global and regional features, respectively. • The multi-task model could assist doctors in selecting patients with invasive lesions who need surgery and choosing appropriate surgical methods.

Intergroupe francophone de cancérologie thoracique, Société de pneumologie de langue française, and Société d'imagerie thoracique statement paper on lung cancer screening

Following the American National Lung Screening Trial results in 2011 a consortium of French experts met to edit a statement. Recent results of other randomized trials gave the opportunity for our group to meet again in order to edit updated guidelines. After literature review, we provide here a new update on lung cancer screening in France. Notably, in accordance with all international guidelines, the experts renew their recommendation in favor of individual screening for lung cancer in France as per the conditions laid out in this document. In addition, the experts recommend the very rapid organization and funding of prospective studies, which, if conclusive, will enable the deployment of lung cancer screening organized at the national level.

Lung nodule radio-guided localization and uniportal video-assisted thoracoscopic surgery resection

Since the introduction of lung nodule radio-guided localization, multiport video-assisted thoracoscopic surgery resection has been widely described. To date, only one series has reported the use of uniportal approach. Our objective is to describe the experience of a single institution of lung nodule radio-guided localization and uniportal video-assisted thoracoscopic surgery resection. Retrospective cohort study based on data from medical records of patients between May 2012 and April 2019. Twenty-four patients were included, 13 were women (54.2%) with a median age of 59.5 years (range 19 and 81 years). Median nodule size was 7 mm (range 3-12 mm) and 19 (79.2%) patients had single lung nodule. The main indication was sub-centimetric nodule in 22 (91.6%) patients followed by a deep localization in 10 (41.6%) patients and sub-solid nodule in 9 (37.5%) patients. Median surgical time was 102.5 min (range 55-160 min). 4 (16.6%) patients had malignant neoplasm of the lung, 10 (41.7%) patients had lung metastases and 10 (41.7%) patients had benign lung lesions. The success rate found was 95.8%. Concordance analysis between palpation of the pulmonary nodule and the presence of the nodule in the histopathology was rated as poor, kappa value - 0.71 (P = 0.186) and between the resection of the pulmonary nodule according to the presence of the nodule in the pathology report was rated as good, Kappa value 0.625 (P = 0.001). Lung nodule radio-guided localization and uniportal video-assisted thoracoscopic surgery resection has a similar success rate and complications to those described by multiport video-assisted thoracoscopic surgery resections.

Risk Factors for The Growth of Residual Nodule in Surgical Patients with Adenocarcinoma Presenting as Multifocal Ground-glass Nodules

PURPOSE

We aim to investigate the risk factors influencing the growth of residual nodule (RN) in surgical patients with adenocarcinoma presenting as multifocal ground-glass nodules (GGNs).

METHOD

From January 2014 to June 2018, we enrolled 238 patients with multiple GGNs in a retrospective review. Patients were categorized into growth group 63 (26.5%), and non-growth group 175 (73.5%). The median follow-up time was 28.2 months (range, 6.3-73.0 months). To obtain the time of RN growth and find the risk factors for growth, data such as age, gender, history of smoking, history of malignancy, type of surgery, pathology and radiological characteristics were analyzed to use Kaplan-Meier method with the log-rank test and Cox regression analysis.

RESULTS

The median growth time of RN was 56.0 months (95% CI, 45.0-67.0 months) in all 238 patients. Roundness (HR 4.62, 95% CI 2.20-9.68), part-solid nodule (CTR ≥ 50%) (HR 4.39, 95% CI 2.29-8.45), vascular convergence sign (HR 2.32, 95% CI 1.36-3.96) of RN, and age (HR 1.04, 95% CI 1.01-1.07) were independent predictors of further nodule growth. However, radiological characteristics and pathology of domain tumour (DT) cannot be used as indicators to predict RN growth.

CONCLUSIONS

RN showed an indolent growth pattern in surgical patients with multifocal GGNs. RN with a higher roundness, presence of vascular convergence sign, more solid component, and in the elder was likely to grow. However, the growth of RN showed no association with the radiological features and pathology of DT.

Nodular distribution pattern on chest computed tomography (CT) in patients diagnosed with nontuberculous mycobacteria (NTM) infections

BACKGROUND

This study evaluated the prevalence of spreading pathways in nontuberculous mycobacteria (NTM) pulmonary infections according to nodular distribution patterns seen on chest computed tomography (CT).

METHODS

This study included 63 patients diagnosed with NTM lung infections who underwent CT at our institution. A retrospective analysis of CT images focused on the presence and distribution of nodules, presence of intrathoracic lymphadenopathy and the predominant side of infection in the lungs. The findings were classified into five groups; centrilobular (bronchogenic spread), perilymphatic (lymphangitic spread), random (hematogenous spread), combined pattern and no nodules present. The groups were then compared according to other CT findings.

RESULTS

Among 51 (81%) patients identified with a nodular pattern on chest CT, 25 (39.8%) presented with centrilobular, 7 (11.1%) with perilymphatic, 6 (9.5%) with random and 13 (20.6%) with combined nodular patterns but located in different areas of the lungs. The right side of the lungs was predominant in 38 cases (60.3%). Intrathoracic lymphadenopathy was evident in 20 patients (31.7%). Significant differences in distributions of nodular patterns were seen in patients infected with Mycoplasma avium complex (MAC) associated with centrilobular pattern (p = 0.0019) and M. fortuitum associated with random pattern (p = 0.0004). Some of the findings were related to perilymphatic nodules between other isolated species of NTM (p = 0.0379).

CONCLUSION

The results of this study showed a high proportion of perilymphatic nodules and right-sided predominance in the upper lobe, which, combined with intrathoracic lymphadenopathy is highly suggestive of the lymphangitic spread of lung NTM infections.

Efficiency of a computer-aided diagnosis (CAD) system with deep learning in detection of pulmonary nodules on 1-mm-thick images of computed tomography

PURPOSE

To evaluate the performance of a deep learning-based computer-aided diagnosis (CAD) system at detecting pulmonary nodules on CT by comparing radiologists' readings with and without CAD.

MATERIALS AND METHODS

A total of 120 chest CT images were randomly selected from patients with suspected lung cancer. The gold standard of nodules ≥ 3 mm was established by a panel of three expert radiologists. Two less experienced radiologists read the images without and afterward with CAD system. Their reading times were recorded.

RESULTS

The radiologists' sensitivity increased from 20.9% to 38.0% with the introduction of CAD. The positive predictive value (PPV) decreased from 70.5% to 61.8%, and the F1-score increased from 32.2% to 47.0%. The sensitivity significantly increased from 13.7% to 32.4% for small nodules (3-6 mm) and from 33.3% to 47.6% for medium nodules (6-10 mm). CAD alone showed a sensitivity of 70.3%, a PPV of 57.9%, and an F1-score of 63.5%. Reading time decreased by 11.3% with the use of CAD.

CONCLUSION

CAD improved the less experienced radiologists' sensitivity in detecting pulmonary nodules of all sizes, especially including a significant improvement in the detection of clinically important-sized medium nodules (6-10 mm) as well as small nodules (3-6 mm) and reduced their reading time.

[Pulmonary histoplasmosis in an immunocompetent patient]

INTRODUCTION

Acute pulmonary histoplasmosis (APH) is rare in an immunocompetent patient. We report a case of APH diagnosed by culture of broncho-alveolar lavage (BAL) in a patient presenting a pseudo-tumoral form with nodules progressing to cavitation.

OBSERVATION

A 41 year-old male smoker was hospitalized with a persistent fever, dry cough and dyspnoea on exertion. The first CT scan showed a reticulo-nodular interstitial infiltrate with lymphadenopathy that progressed rapidly to multiple pulmonary nodules with central cavitation. Bronchial endoscopy, with BAL culture, provided the diagnosis of Histoplasma capsulatum, variety capsulatum. The infection may have occurred during work in a hangar in Guadeloupe that was scattered with bats' guano. After two months of treatment by itraconazole, the patient's condition improved clinically and radiologically with reduction of the nodules and their cavitation.

CONCLUSION

This case presents an immunocompetent patient with pulmonary histoplasmosis and multiple, radiologically atypical, nodules. The diagnosis was established by BAL culture.

Impact of a Health Information Technology Intervention on the Follow-up Management of Pulmonary Nodules

Lung cancer is the leading cause of cancer deaths in the USA. The most common abnormalities suspicious for lung cancer on CT scan include pulmonary nodules. Recommendations to improve care for patients with pulmonary nodules require follow-up management. However, transitions in care, especially for patients undergoing transitions to ambulatory care sites from the emergency department (ED) and inpatient settings, can exacerbate failures in follow-up testing and compromise patient safety. We evaluate the impact of a discharge module that includes follow-up recommendations for further management of pulmonary nodules on the study outcome and follow-up management of patients with pulmonary nodules within 1 year after discharge. After IRB approval, we collected data on all patients undergoing chest or abdominal CT exams over a 12-month baseline and 12-month intervention period at an academic medical center. The inpatient discharge module was implemented in November 2011; the ED module was implemented in May 2012. Multivariable logistic regression was performed to account for care setting, imaging modality, recommendations, and patient demographics. Implementation of a discharge module resulted in improved follow-up of patients with pulmonary nodules within 1 year after discharge (OR = 1.64, p = 0.01); the ED implementation resulted in better follow-up compared to the inpatient module (OR = 2.24, p < 0.01). Twenty-seven percent of patients with pulmonary nodules received follow-up management, which, although significantly improved from the 18% baseline, remains low. An electronic discharge module is associated with improved follow-up management of patients with pulmonary nodules, and may be combined with interventions to further improve management of these patients.

[Progress in Basic Research and Clinical Treatment of Multiple Pulmonary Nodules]

肺癌是世界上发病率和死亡率最高的肿瘤。随着多层螺旋计算机断层扫描（computed tomography, CT）技术的发展和肺癌筛查的广泛开展，越来越多的肺结节被发现, 其中不少是多发肺结节，这些结节在病理学上常被诊断为多原发肺腺癌。对于具有不同影像学特征的多发结节，首选处理方法不尽相同，且每个肺结节的处理方法仍存在很大争议。近年来多发肺结节各病灶的演进及病灶间的相互影响机制，病灶内和病灶间肿瘤细胞在基因组学方面的同质性和异质性也备受关注。本文从组织病理学、基因组学、外科处理等多方面综合论述多发肺结节的研究进展。

The clinical significance of indeterminate pulmonary nodules in melanoma patients at baseline and during follow-up chest CT

Objective

This study aims to determine an appropriate timeline to monitor indeterminate pulmonary nodules (IPN) in melanoma patients to confirm metastatic origin.

Materials and Methods

588 clinically non-metastatic melanoma patients underwent curative intent surgery during 3 years. Patients with baseline chest CT and at least one follow-up (FU) CT were retrospectively analyzed to assess for IPN. Patients with definitely benign nodules, metastases and non-melanoma malignancies were excluded. Change in volume from first to FU CT, initial diameter (D1) and volume (V1), distance from pleura, peripheral and perifissural location, density and clinical stage were evaluated. Nodules were volumetrically measured on CTs and were considered metastases if they increased in size between two CTs or if increase was accompanied by multiple new nodules or extrapulmonary metastases.

Results

148 patients were included. Two out of 243 baseline IPN detected in 70 patients, increased significantly in volume in 3 and 5 months and were proven metastases. During FU, 86% of 40 interval IPN detected in 28 patients, were proven metastases. Interval nodule (p < 0.0001, HR:243,CI:[57.32,1033.74]), 3-month volume change (OR:1.023,CI:[1.014,1.033]), V1 (OR:1.006,CI:[1.003,1.009]), D1 (OR:1.424,CI:[1.23,1.648]), distance from pleura (OR:1.03,CI:[1.003,1.059]), and combined stage IIC + III (OR:11.29,CI:[1.514,84.174]), were associated with increased risk for metastasis. 43%, 72% and 94% of patients with IPN were confirmed with metastases in the first FU CT at 3, 6 and 12 months respectively.

Conclusion

Baseline IPN are most likely benign, while interval IPN are high risk for metastasis. Absence of volume increase of IPN within 6 months excluded metastasis in most patients.

[Diffuse pulmonary meningotheliomatosis: a case report and literature review]

Objective: To analyze the clinical features, diagnosis and differential diagnosis of diffuse pulmonary meningotheliomatosis (DPM), a rare subtype of minute pulmonary meningothelial-like nodules (MPMN), so as to improve the understanding of this disorder. Methods: The clinical data of a patient diagnosed as DPM admitted in department of Respiratory Medicine, Peking University Third Hospital in August 2016 were reported and the related literatures were reviewed. With "pulmonary meningothelial-like nodules" , "minute pulmonary meningothelial-like nodules" or "diffuse pulmonary meningotheliomatosis" as the search terms, and the search time before November 1st 2017 for Wanfangdata, China National Knowledge Infrastructure (CNKI), and PubMed.Twenty-five articles were retrieved, among which 6 English (all case reports) articles were found with the search term "diffuse pulmonary meningotheliomatosis" involving 10 cases, and the other 19 articles (1 Chinese, 18 English) about MPMN mainly discussed non-DPM cases,including 13 case reports and 6 pathological/genetic studies. Results: A 68-year old female was admitted to the hospital because of intermittent cough and expectoration for more than 3 years and aggravation for 3 weeks. Her pulmonary CT showed diffuse minute nodules distributed randomly throughout both lungs, and did not improve after treatment with oral Moxifloxacin for 2 weeks. A video-assisted thoracoscopic biopsy was performed. The specimens showed MPMN and no other lesions, which confirmed the final diagnosis of DPM. She was followed without any medication therapy and her pulmonary CT showed stabilization of the lesions one year later. DPM was considered as a rare type of MPMN. A total of 11 cases were analyzed, including 10 cases reported in the literature. The patients included 1man and 10 women, aged 51 to 75 years, with an average age of (64±8) years. Among the 11 patients, 8 denied a history of smoking or of occupational exposure, 7 presented with dyspnea, shortness of breath, or fatigue, and 8 had mild abnormalities of pulmonary function test. The pulmonary CT of all the patients showed randomly distributed, diffuse bilateral small solid or ground-glass nodules, with the diameters less than 5 millimeters, some of which were cavitated. Only 1 patient had pulmonary thromboembolism, while the other 10 did not have any other lung diseases. All the patients were histologically diagnosed, 8 by open lung biopsies, 2 by transbronchial lung biopsy, and 1 by CT-guided fine needle aspiration. Three patients were followed for 12-92 months and the lung lesions were all stable. Conclusions: As a rare subtype of MPMN, DPM lacks specificity of clinical manifestations, and presents with diffuse bilateral small solid or ground-glass nodules, distributed randomly throughout both lungs. An early correct diagnosis depends on biopsy.

Rheumatoid pulmonary nodules: clinical and imaging features compared with malignancy

OBJECTIVES

The objective of this study was to identify clinical and imaging features that distinguish rheumatoid lung nodules from malignancy.

METHODS

We conducted a retrospective review of 73 rheumatoid patients with histologically-proven rheumatoid and malignant lung nodules encountered at Mayo Clinic, Rochester, MN (2001-2016). Medical records and imaging were reviewed including a retrospective blinded review of CT and PET/CT studies.

RESULTS

The study cohort had a mean age of 67 ± 11 years (range 45-86) including 44 (60%) women, 82% with a smoking history, 38% with subcutaneous rheumatoid nodules, and 78% with rheumatoid factor seropositivity. Subjects with rheumatoid lung nodules compared to malignancy were younger (59 ± 12 vs 71 ± 9 years, p < 0.001), more likely to manifest subcutaneous rheumatoid nodules (73% vs 20%, p < 0.001) and rheumatoid factor seropositivity (93% vs 68%, p = 0.034) but a history of smoking was common in both groups (p = 0.36). CT features more commonly associated with rheumatoid lung nodules compared to malignancy included multiplicity, smooth border, cavitation, satellite nodules, pleural contact, and a subpleural rind of soft tissue. Optimal sensitivity (77%) and specificity (92%) (AUC 0.85, CI 0.75-0.94) for rheumatoid lung nodule were obtained with ≥ 3 CT findings (≥ 4 nodules, peripheral location, cavitation, satellite nodules, smooth border, and subpleural rind). Key ¹⁸FDG-PET/CT features included low-level metabolism (SUV_max 2.7 ± 2 vs 7.2 ± 4.8, p = 0.007) and lack of ¹⁸F-fluorodeoxyglucose (FDG)-avid draining lymph nodes.

CONCLUSION

Rheumatoid lung nodules have distinct CT and PET/CT features compared to malignancy. Patients with rheumatoid lung nodules are younger and more likely to manifest subcutaneous rheumatoid nodules and seropositivity.

KEY POINTS

• Rheumatoid lung nodules have distinct clinical and imaging features compared to lung malignancy. • CT features of rheumatoid lung nodules include multiplicity, cavitation, satellite nodules, smooth border, peripheral location, and subpleural rind. • Key PET/CT features include low-level metabolism and lack of FDG-avid draining lymph nodes.

Surgical Treatment of Primary Pulmonary Myopericytoma

Myopericytoma is a benign tumor that occurs in soft tissues. Myopericytoma in the lungs is very rare. We report the case of a 63-year-old woman presenting with cavitary masses in the left lung and multiple tiny nodules in both lungs. She underwent surgery, and a histological examination revealed primary pulmonary myopericytoma.

[Interstitial lung disease and pancreatic cancer: Series of two cases]

INTRODUCTION

Pancreatic cancer is often not diagnosed until at a metastatic stage at which point the prognosis is very poor. Pulmonary metastases are pleomorphic, often present at the time of diagnosis and can lead to the discovery of an asymptomatic primary disease.

CASE REPORT

We describe two cases aged 60 and 74 years, where imaging identified what was thought to be an interstitial lung disease but which was actually metastasis from pancreatic cancer. In the first case, CT showed multiple excavated pulmonary nodules but the presentation with medullary compression led rapidly to pathological diagnosis on bone lesions. In the second patient, a history of rheumatoid arthritis and the lack of abdominal symptoms led to an initial search for disease related to the rheumatoid disease. Histopathology, from lung and bone biopsies, enabled a correct diagnosis to be achieved.

CONCLUSION

Where atypical interstitial lung disease occurs, biopsy should be considered in order not to delay a diagnosis of cancer, especially pancreatic cancer.

Benign Pulmonary Metastasizing Leiomyoma of the Uterus

Benign Metastasizing Leiomyoma (BML) is a rare disease which represents with multiple leiomyomatous lesions in many tissues and organs especially in lungs. These patients have been operated for leiomyoma of the uterus. Here we report a case of a 41-year-old woman who was evaluated in a thoracic surgery hospital for dyspnea and bilateral nodules in chest roentgenogram. She had no history of neoplasm, only myomectomy history of uterine leiomyoma 10 years ago. Biopsy and histopathological examination were consistent with pulmonary leiomyoma. The patient was reffered to our clinic and we performed a total abdominal hysterectomy for her multiple uterine leiomyomas. The final diagnosis was 'benign pulmonary metastasizing leiomyoma'. After this diagnosis, surgical castration was performed but two years later, repeat imaging showed progression in pulmonary lesions and progesterone therapy was administered to the patient. Patient has continued on this hormonal therapy to date and during the 5-years follow-up, the persisting lesions in both lungs regressed.

[Hydatidosis simulating a cardiac tumour with pulmonary metastases]

BACKGROUND

The presence of multiple symptomatic pulmonary nodules and one cardiac tumour in a child requires urgent diagnosis and treatment. Until a few decades ago, the diagnosis of a cardiac tumour was difficult and was based on a high index of suspicion from indirect signs, and required angiocardiography for confirmation. Echocardiography and other imaging techniques have also helped in the detection of cardiac neoplasms. However, it is not always easy to make the correct diagnosis.

CLINICAL CASE

The case is presented of a 12 year-old boy with pulmonary symptoms, and diagnosed with a cardiac tumour with lung metastases. The presence of numerous pulmonary nodules was confirmed in our hospital. The echocardiogram detected a solid cardiac nodule in the right ventricle. Magnetic resonance imaging confirmed the findings and the diagnosis. Puncture-aspiration of a lung nodule gave the diagnosis of hydatidosis. He underwent open-heart surgery with cardiac cyst resection and treated with anthelmintics. The lung cysts were then excised, and he recovered uneventfully.

DISCUSSION

This child had multiple pulmonary nodules and a solid cardiac nodule, and was suspected of having a cardiac tumour with pulmonary metastases. However, given the clinical history, background and morphology of pulmonary nodules, another possible aetiology for consideration is echinococcosis. The clinical picture of cardiac hydatidosis and its complications is highly variable. The clinical history is essential in these cases, as well as having a high index of suspicion.

CONCLUSION

Hydatidosis should be included in the differential diagnosis of a solid, echogenic, cardiac nodule. The treatment for cardiopulmonary hydatid cysts is surgical, followed by anthelmintics.

Cryoablation of a small pulmonary nodule with pure ground-glass opacity: a case report

Treatments for pure ground-glass nodules (GGNs) include limited resection; however, surgery is not always possible in patients with limited pulmonary functional reserve. In such patients, cryoablation may be a suitable alternative to treat a pure GGN. Here, we report our initial experience with cryoablation of a pure GGN that remained after repeated surgical resection in a patient with multiple GGNs. A 5-mm-sized pure GGN in the left lower lobe was cryoablated successfully without recurrence at the 6-month follow-up.

Risk of malignancy in pulmonary nodules: A validation study of four prediction models

OBJECTIVES

Clinical prediction models assess the likelihood of malignancy in pulmonary nodules detected by computed tomography (CT). This study aimed to validate four such models in a UK population of patients with pulmonary nodules. Three models used clinical and CT characteristics to predict risk (Mayo Clinic, Veterans Association, Brock University) with a fourth model (Herder et al. [4]) additionally incorporating (18)Fluorine-Fluorodeoxyglucose (FDG) avidity on positron emission tomography-computed tomography (PET-CT).

MATERIALS AND METHODS

The likelihood of malignancy was calculated for patients with pulmonary nodules (4-30mm diameter) and data used to calculate the area under the receiver operating characteristic curve (AUC) for each model. The models were used in a restricted cohort of patients based on each model's exclusion criteria and in the total cohort of all patients.

RESULTS

Two hundred and forty-four patients were studied, of whom 139 underwent FDG PET-CT. Ninety-nine (40.6%) patients were subsequently confirmed to have malignant nodules (33.2% primary lung cancer, 7.4% metastatic disease). The Mayo and Brock models performed similarly (AUC 0.895 and 0.902 respectively) and both were significantly better than the Veterans Association model (AUC 0.735, p<0.001 and p=0.002 respectively). In patients undergoing FDG PET-CT, the Herder model had significantly higher accuracy than the other three models (AUC 0.924). When the models were tested on all patients in the cohort (i.e. including those outside the original model inclusion criteria) AUC values were reduced, yet remained high especially for the Herder model (AUC 0.916). For sub-centimetre nodules, AUC values for the Mayo and Brock models were 0.788 and 0.852 respectively.

CONCLUSIONS

The Mayo and Brock models showed good accuracy for determining likelihood of malignancy in nodules detected on CT scan. In patients undergoing FDG PET-CT for nodule evaluation, the highest accuracy was seen for the model described by Herder et al. incorporating FDG avidity.

Case of pulmonary cryptococcosis mimicking hematogeneous metastases in an immunocompetent patient: value of absent 18F-fluorodeoxyglucose uptake on positron emission tomography/CT scan

The radiologic appearance of multiple discrete pulmonary nodules in immunocompetent patients, with cryptococcal infection, has been rarely described. We describe a case of pulmonary cryptococcosis, presenting with bilaterally and randomly distributed nodules on a computed tomography, mimicking hematogeneous metastases. Positron emission tomography does not demonstrate 18F-fluorodeoxyglucose (FDG) uptake, suggesting a low probability for malignancy, which is a crucial piece of information for clinicians when making a management decision. We find the absence of FDG uptake correlates with the pathologic finding of an infectious nodule, composed of fibrosis and necrosis.

[Acute respiratory failure due to Mycoplasma pneumonia]

INTRODUCTION

Respiratory infections due to Mycoplasma pneumoniae are typically mild and subacute. We report the case of a 40-year-old man hospitalized for acute respiratory distress in the context of an acute infection with Mycoplasma pneumoniae. Radiological and pulmonary function test were consistent with an acute infectious bronchiolitis.

CASE REPORT

The patient presented with isolated respiratory failure with profound hypoxemia requiring oxygen delivered at high concentration by face mask. The CT appearance of the lesions corresponded to a spread of bilateral micro-connected pulmonary nodules (a "tree-in-bud" pattern) associated with obstructive ventilatory disorder. The only pathogen identified by PCR on BAL and serology was Mycoplasma pneumoniae. The evolution was favorable with antibiotic therapy combined with corticosteroids.

CONCLUSION

Mycoplasma pneumoniae may be responsible for severe respiratory illness in the form of bronchiolitis. In the setting of severe acute community pneumoniae antibiotic treatment which is also effective against Mycoplasma pneumonia should be considered. In this case, corticosteroids may be an effective adjunct by their action on the small airways.

A case of secondary syphilis presenting as multiple pulmonary nodules

Syphilis is a sexually transmitted disease caused by Treponema pallidum. The prevalence of this disease has recently increased worldwide. However, pulmonary involvement in secondary syphilis is extremely rare. A 51-year-old heterosexual male patient presented with multiple pulmonary nodules with reactive serology from the Venereal Disease Research Laboratory test and positive fluorescent treponemal antibody absorption testing. A hematogenous metastatic malignancy was suspected and an excisional lung biopsy was performed. Histopathological examination showed only central necrosis with abscess and plasma cell infiltration, but no malignant cells. The patient reported sexual contact with a prostitute 8 weeks previously and a penile lesion 6 weeks earlier. Physical examination revealed an erythematous papular rash on the trunk. Secondary syphilis with pulmonary nodules was suspected, and benzathine penicillin G, 2.4 million units, was administered. Subsequently, the clinical signs of syphilis improved and the pulmonary nodules resolved. The final diagnosis was secondary syphilis with pulmonary nodular involvement.

Pulmonary hyalinizing granuloma in HIV/AIDS

A 55-year-old man who was recently diagnosed with HIV/AIDS developed multiple bilateral pulmonary nodules after starting highly active antiretroviral therapy. Workup confirmed the diagnosis of pulmonary hyalinizing granuloma. This is the first described case of pulmonary hyalinizing granuloma in HIV/AIDS, and may represent a rare form of immune reconstitution inflammatory syndrome.

Isolated pulmonary cryptococcosis in an immunocompetent boy

Pulmonary cryptococcosis is rare in immunocompetent subjects. Here, we present the case of a 16-year-old boy who was referred to our pediatric department for the management of multiple consolidations detected on chest radiography, which was routinely performed when the patient was being evaluated for an ankle fracture. Fine needle aspiration biopsy was performed, and the definitive diagnosis was established as cryptococcal pneumonia. After 8 weeks of antifungal treatment, the pulmonary nodules on the chest radiographs disappeared.