Surgical diagnosis and treatment of a solitary lung nodule of IgG4-related disease, mimicking primary lung carcinoma or metastatic lung tumour: A rare case

INTRODUCTION

IgG4-related disease is a poorly understood immune disorder. Its features include tumour-like swelling of involved organs, lymphoplasmacytic infiltrate with IgG4 positive plasma cells. IgG4-related lung disease can manifest radiologically as various types of pulmonary abnormalities, including mass-like lesions and pleural effusion, and it may mimic malignant disease.

PRESENTATION OF CASE

A 76-year-old man was found to have a 4-mm ground glass opacity in the left lower lobe of the lung on follow-up chest CT after surgery for colon carcinoma. This lesion gradually became consolidated and enlarged to 9 mm over about three years. We performed a video-assisted left basal segmentectomy for the purposes of both diagnosis and treatment. Pathological examination revealed lymphoplasmacytic infiltration, mainly with IgG4-positive plasma cells.

DISCUSSION

A major characteristic of IgG4-related lung disease is multiple, small, bilateral, lung nodules and solid nodules reportedly being detected in almost all patients. However, solitary nodules are rare, being present in only 14 %. Moreover, this case shows extremely rare radiological findings in which a ground-glass opacity had gradually morphed into a solid nodule. It is difficult to differentiate IgG4-related lung nodules from other lung diseases, such as primary or metastatic lung tumours, standard interstitial pneumonia, organizing pneumonia.

CONCLUSION

We have here presented a rare case of IgG4-related lung disease with a 3-year course, including detailed radiological findings. Surgery is very useful for both diagnosis and treatment of a small, solitary, deeply located, pulmonary nodule of IgG4-related lung disease.

Multi-task deep learning network to predict future macrovascular invasion in hepatocellular carcinoma

BACKGROUND

Models predicting future macrovascular invasion in hepatocellular carcinoma are constructed to assist timely interventions.

METHODS

A total of 366 HCC cases were retrospectively collected from five Chinese hospitals between April 2007 and November 2016: the training dataset comprised 281 patients from four hospitals; the external validation dataset comprised 85 patients from another hospital. Multi-task deep learning network-based models were constructed to predict future macrovascular invasion. The discrimination, calibration, and decision curves were compared to identify the best model. We compared the time to macrovascular invasion and overall survival using the best model and related image heterogeneity scores (H-score). Then, we determined the need for a segmentation subnet or the replacement deep learning algorithm by logistic regression in screening clinical/radiological factors. Finally, an applet was constructed for future application.

FINDINGS

The best model combined clinical/radiological factors and radiomic features. It achieved best discrimination (areas under the curve: 0·877 in the training dataset and 0·836 in the validation dataset), calibration, and decision curve. Its performance was not affected by the treatments and disease stages. The subgroups had statistical significance for time to macrovascular invasion (training: hazard ratio [HR] = 0·073, 95% confidence interval [CI]: 0·032-0·167, p < 0·001 and validation: HR = 0·090, 95%CI: 0·022-0·366, p < 0·001) and overall survival (training: HR = 0·344, 95%CI: 0·246-0·547, p < 0·001 and validation: HR = 0·489, 95%CI: 0·279 - 0·859, p = 0·003). Similar results were achieved when the patients were subdivided by the H-score. The subnet for segmentation and end-to-end deep learning algorithms improved the performance of the model.

INTERPRETATION

Our multi-task deep learning network-based model successfully predicted future macrovascular invasion. In high-risk populations, besides the current first-line treatments, more therapies may be explored for macrovascular invasion.

Lung nodules and IgG4 related disease: a single-center based experience

BACKGROUND

This study was undertaken in an attempt to characterize the frequency and clinical features of lung nodules in IgG4 related disease (IgG4-RD) patients as an insight for help with the diagnosis of lung nodules.

METHODS

A retrospective study was carried out in West China Hospital, Sichuan University from January 2012 to December 2018, 89 patients with definite IgG4-RD were enrolled.

RESULTS

Fifty of 89 patients with definite IgG4-RD had radiologically confirmed lung nodules, 6 of whom were diagnosed with definite IgG4 related lung disease. Lung nodules detected in more than 40 patients were small and solid, always with regular margins. Multiple (41/50) and bilateral (34/50) distributions was also a major characteristic of these lung nodules. Lobulation and speculation were simultaneously detected in 3 patients, including 2 patients combined with pleural indentation. Calcification of nodules was detected in only one patient. Thirty-seven patients also had additional radiological abnormalities of lungs, including ground-glass opacity (21/50), thickening of pleura (9/50), thickening of interlobular septa (4/50), thickening of bronchial wall (3/50), pleural effusion (4/50), mass (3/50), interstitial changes (5/50), and mediastinal or hilar lymphadenopathy (32/50). Most patients (44/50) were treated with glucocorticoids alone or combined with immunosuppressive agents. Sixteen patients received a re-examination by chest computed tomography (CT) scan after treatment, 10 of whom showed a decrease in the size and/or the number of nodules.

CONCLUSIONS

The incidence of lung nodules in IgG4-RD patients can be high. For an IgG4-RD patient with lung nodules, the possibility that the lung nodules related to IgG4-RLD is high. It is hard to differentiate IgG4 related lung nodules from other lung diseases, in particular, lung cancer. Radiological characteristics and positive responses to glucocorticoids and immunosuppressive agents can help with the differential diagnosis. For these patients, regular follow-up is also important.

A new formulation of polymer gel dosimeter with reduced toxicity: Dosimetric characteristics and radiological properties

The present study aimed to produce a new, less toxic, and cost-effective polymer gel dosimeter using potassium salt of 2-acrylamido-2 methyl-propane sulfonic acid (AMPS) monomer. The new formulation was called PAKAG. The irradiation of PAKAG polymer gel dosimeter was performed using a 6 MV clinical linear accelerator, and its response was evaluated using magnetic resonance imaging. The obtained images were post-processed to produce related R₂ maps. Afterward, the Dose-R₂ calibration curves were obtained. Response dependence on the imaging temperature was examined. Furthermore, response stability over time was investigated. To investigate the radiological characteristics, the elemental composition, effective atomic number, electron density, and photon attenuation coefficient of PAKAG polymer gel dosimeter were calculated. A maximum sensitivity of 0.152±0.007 with the goodness of fit of R²=0.999 in a dynamic range of 0-6Gy at 12h post-irradiation time was found. Such as other polymer gel dosimeter, the response of PAKAG polymer gel dosimeter was dependent on post-irradiation time and imaging temperature. Finally, it was concluded that the PAKAG polymer gel dosimeter could be used as a less toxic and cost-effective polymer gel dosimeter.

The clinicoradiological features and surgical outcomes of primary intracranial fibrosarcoma: a single-institute experience with a systematic review

Primary intracranial fibrosarcoma (PIF) was a rare tumor with a high relapse rate and dismal survival rate. This study aimed to delineate the clinical characteristics of primary intracranial fibrosarcoma (PIF) and the risk factors for outcomes. We reviewed 15 PIF patients, who underwent surgical treatment at our institution from January 2009 to December 2018. Meanwhile, 36 cases from the prior literature between November 1962 and December 2019 were also retrieved and pooled to identify the risk factors. In our cohort, while cystic component (46.7%), perilesional edema (83.3%), and vascular flow void (66.7%) were commonly observed, no patient was accurately diagnosed. The 2-year relapse-free survival (RFS) and overall survival (OS) were 12.2% and 30.2%, respectively. Based on the pooled data, tumor size (p = 0.006), Ki-67 index (p = 0.004), and radiotherapy dose (p = 0.029) were prognostic factors for RFS in univariate analysis. In the univariate analysis, tumor size (p = 0.002), NGTR (p = 0.049), and high Ki-67 index (p = 0.019) were significant predictors for OS; and further multivariate analysis (n = 18) showed that large tumor size (≥ 5 cm; HR 14.613, p = 0.022) and high Ki-67 index (≥ 30%; HR 5.879, p = 0.020) were the independent risk factors for OS. Due to the rarity and nonspecific clinicoradiological features, the correct diagnosis of PIF before surgery was challenging. The outcomes of PIF were poor, and GTR plus radiotherapy (at least 60 Gy) might benefit to the outcomes and were recommended. Future study with a large cohort was needed to verify our findings.

Radiological Characteristics and Surgical Outcome of Patients with Long Ossification of the Posterior Longitudinal Ligament Resulting in Ossified Lesions in the Upper Cervical Spine

OBJECTIVE

Designing surgical strategies for ossified lesions in the upper cervical spine is challenging owing to the complex anatomic structures. The present study aimed to clarify the prevalence of ossified lesions in the upper cervical spine in patients with ossification in the posterior longitudinal ligament and illustrate the clinical features, radiological findings, and surgical outcomes of this abnormality.

METHODS

Demographic and clinical data were collected for all patients preoperatively and included age, gender, body mass index, alcohol and tobacco use, history of diabetes, visual analog score, and Japanese Orthopaedic Association score. The cervical angle, morphology of ossification in the posterior longitudinal ligament, K-line, occupation ratio, space available for the spinal cord, high-intensity zone, and compression ratio of the spinal cord were calculated. The operative approach, technique used, and complications were recorded.

RESULTS

A total of 38 patients were enrolled. The upper cervical segment in 23 patients was not surgically addressed. In the group with the upper cervical segment addressed surgically, 10 patients were treated with C3-C6 open-door laminoplasty and C2 partial laminectomy, 1 with C1-C7 laminoplasty, 1 with C2-C7 laminoplasty, 2 with C3-C6 total and C2 partial laminectomy, and 1 with C1-C5 laminectomy and occipitocervical fusion.

CONCLUSIONS

The development of ossified lesions in the upper cervical spine has a high incidence. Decompressive surgery for upper cervical spine segments should be recommended for patients with severe narrowing of the spinal canal and a high signal intensity that extends to the upper cervical segment of the spinal cord. We hope that the findings from the present study will aid in clinical decision-making and provide useful information that can be incorporated into future guidelines.

Appropriate surgical procedures for Chiari type 1 malformation and associated syrinx based on radiological characteristics of the craniovertebral junction

Several surgical procedures can be applied for syrinx associated with Chiari type 1 malformation; however, it remains controversial as to which approach is the most effective. Here, we evaluated the indications and limitations of foramen magnum decompression (FMD) with or without dural plasty. Forty patients with Chiari type 1 malformation were surgically treated and followed up for > 12 months. Thirty-two patients (80.0%) underwent FMD with removal of only the outer dura mater layer, while eight patients underwent FMD with dural plasty. We evaluated surgery-related complications and preoperative radiological findings affecting syrinx shrinkage rates. Post-surgery, the mean syrinx shrinkage rates were 0.32 ± 0.44 in the outer layer-removal group and 0.72 ± 0.27 in the dural plasty group (P = 0.012). Surgery-related complications were less frequent, but reoperation was more frequent, in the outer layer-removal group. The extent of tonsillar descent significantly affected syrinx shrinkage in FMD with outer layer removal (P = 0.042). The outcomes of both approaches in patients with tonsillar descent < 10.0 mm were similar. The dura mater in the posterior fossa was thin, necessitating dural plasty with FMD, while the spinal dura was sufficiently thick for removal of the outer layer in the Chiari patients. These histological differences corresponded with the inferior margin of the cerebellar tonsil. Recognizing the appropriate surgical indication for achieving good post-procedural outcomes is necessary for reducing complications and improving outcomes of FMD for Chiari type 1 malformations.

A new less toxic polymer gel dosimeter: Radiological characteristics and dosimetry properties

PURPOSE

A new polymer gel dosimeter recipe was investigated that may be more suitable for widespread applications than polyacrylamide gel dosimeters, since the extremely toxic acrylamide has been replaced with the less harmful monomer 2-Acrylamido 2-Methyl Propane Sulfonic acid (AMPS).

METHODS

The new formulation was named PAMPSGAT. The MRI response (R2) of the dosimeters was analyzed for conditions of varying dose, dose rate, and temperature during scanning. Radiological properties of the PAMPSGAT polymer gel dosimeter were investigated.

RESULTS

The dose-response (R2) of AMPS/Bis appears to be linear over a dose range 10-40 Gy. The percentage of difference between the R2 values for imaging at 15 °C and MRI room temperature is about 4.6% for vial with 40 Gy absorbed dose which decreased to less than 1% for imaging at 20 °C. The percentage difference of Zeff of PAMPSGAT gel and soft tissue was less than 1% in the practical energy range (100 KeV-100 MeV). The electron density of the PAMPSGAT polymer gel was 2.9% higher than that of muscle. Results showed that the sensitivity of PAMPSGAT polymer gel dosimeter irradiated by ⁶⁰Co (energy = 1.25 MeV) is about 27.7% higher than that of irradiated using a 6 MeV Linac system.

CONCLUSIONS

Temperature during MRI scanning has a small effect on the R2 response of the PAMPSGAT polymer gel dosimeter. Results confirmed tissue equivalency of the PAMPSGAT polymer gel dosimeter in most practical energy range. The PAMPSGAT polymer gel dosimeter response depends on energy and dose rate.

Anatomic Features of Paraclinoid Aneurysms: Computed Tomography Angiography Study of 144 Aneurysms in 136 Consecutive Patients

BACKGROUND

Paraclinoid aneurysms are among the most challenging aneurysms to treat. Computed tomography (CT) angiography helps in evaluating the radiological characteristics of these aneurysms next to bony structures.

OBJECTIVE

To present the CT angiography characteristics of paraclinoid aneurysms in order to better understand such pathology.

METHODS

The study examined CT angiography-based anatomical characteristics obtained retrospectively from 136 patients with 144 paraclinoid aneurysms selected from single-defined catchment populations in Finland. We examined the diameters of the parent artery (internal carotid artery), the location of the aneurysm, its dimensions (width, height, neck), and aneurysm wall irregularity.

RESULTS

We analyzed 144 paraclinoid aneurysms in 136 patients admitted to the hospital during 2000-2014. Multivariable analysis reveals that rupture aneurysms have the following radiological features: aneurysm larger than 5 mm in diameter (P = .006), irregular wall (P = .046), superior location, larger aspect ratio (P = .039), and neck wider than parent artery (P < .001).

CONCLUSION

Smaller diameter of the internal carotid artery and superior location, as well as a large and irregular aneurysm wall, are radiological characteristics of ruptured paraclinoid aneurysms, which CT angiography can measure easily.

The presentation, treatment and outcome of periosteal chondrosarcoma in the Netherlands

In this case study, we describe the clinical presentation and treatment of 36 patients with periosteal chondrosarcoma collected over a 59-year period by the archive of the Netherlands Committee on Bone Tumours. The demographics, clinical presentation, radiological features, treatment and follow-up are presented with the size, location, the histological grading of the tumour and the survival. We found a slight predominance of men (61%), and a predilection for the distal femur (33%) and proximal humerus (33%). The metaphysis was the most common site (47%) and the most common presentation was with pain (44%). Half the tumours were classified histologically as grade 1. Pulmonary metastases were reported in one patient after an intra-lesional resection. A second patient died from local recurrence and possible pulmonary and skin metastases after an incomplete resection. It is clearly important to make the diagnosis appropriately because an incomplete resection may result in local recurrence and metastatic spread. Staging for metastatic disease is recommended in grade II or III lesions. These patients should be managed with a contrast-enhanced MRI of the tumour and histological confirmation by biopsy, followed by en-bloc excision.