CT-based response assessment of advanced gastrointestinal stromal tumor: Dual energy CT provides a more predictive imaging biomarker of clinical benefit than RECIST or Choi criteria

Objectives

Dual-energy CT (DECT) allows quantification of intravenously injected iodinated contrast media in tumors, and therefore may be considered as a surrogate marker for perfusion and tumor vascularity. This study evaluated whether newly developed DECT response criteria allow better correlation with survival than established response criteria.

Methods

Seventeen patients with advanced GIST treated with tyrosine-kinase-inhibitors were assessed by contrast-enhanced DECT 2 and 6 months after beginning of treatment. Response to treatment of 165 tumor lesions was evaluated according to RECIST, Choi criteria and newly developed DECT criteria, defining non-responders as an increase of both tumor size >20% and iodine related attenuation or either a >50% increase of tumor size or iodine related attenuation. All other patients were classified as responders. Progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan–Meier analysis.

Results

Choi criteria and DECT showed a significantly longer median PFS of patients rated as responders than patients rated as non-responders (9–29 months vs. 2–6 months; p < 0.02) at follow-up. Only DECT analysis at 6 months follow-up allowed a valid prediction of OS.

Conclusion

This study indicates that DECT allows a better prediction of therapeutic benefit in advanced GIST patients treated with tyrosine-kinase-inhibitors than established response criteria. However, the most important predictive biomarker of therapeutic benefit was absence of progression, no matter which response evaluation criteria were applied.     

Size determination and response assessment of liver metastases with computed tomography—Comparison of RECIST and volumetric algorithms

Objective

To compare different three-dimensional volumetric algorithms (3D-algorithms) and RECIST for size measurement and response assessment in liver metastases from colorectal and pancreatic cancer.

Methods

The volumes of a total of 102 liver metastases in 45 patients (pancreatic cancer, n = 22; colon cancer, n = 23) were estimated using three volumetric methods (seeded region growing method, slice-based segmentation, threshold-based segmentation) and the RECIST 1.1 method with volume calculation based on the largest axial diameter. Each measurement was performed three times by one observer. All four methods were applied to follow-up on 55 liver metastases in 29 patients undergoing systemic treatment (median follow-up, 3.5 months; range, 1–10 months). Analysis of variance (ANOVA) with post hoc tests was performed to analyze intraobserver variability and intermethod differences.

Results

ANOVA showed significant higher volumes calculated according to the RECIST guideline compared to the other measurement methods (p < 0.001) with relative differences ranging from 0.4% to 41.1%. Intraobserver variability was significantly higher (p < 0.001) for RECIST and threshold based segmentation (3.6–32.8%) compared with slice segmentation (0.4–13.7%) and seeded region growing method (0.6–10.8%). In the follow-up study, the 3D-algorithms and the assessment following RECIST 1.1 showed a discordant classification of treatment response in 10–21% of the patients.

Conclusions

This study supports the use of volumetric measurement methods due to significant higher intraobserver reproducibility compared to RECIST. Substantial discrepancies in tumor response classification between RECIST and volumetric methods depending on applied thresholds confirm the requirement of a consensus concerning volumetric criteria for response assessment.     

Evaluation of inter-observer variability according to RECIST 1.1 and its influence on response classification in CT measurement of liver metastases

ObjectiveThe aim of this study is the evaluation of inter-observer variability in the measurement of liver metastases according to RECIST and its influence on response classification.Patients and methodsA total of 100 radiologists measured liver target lesions, on pre- and post-chemotherapy CT scans of three patients. Each observer filled out a questionnaire about his personal and work features. The evaluations of a well experienced radiologist, considered as “the gold standard”, were compared to those taken by the observers.The percentage of the observers in agreement with the reviewer, in terms of the response category and in terms of inter-observer variability, was calculated for each patient.ResultsThe percentage of the inter-observer agreement was elevated. Most of the observers in agreement with the reviewer were senior radiologists, while those who disagreed were junior radiologist, but this result did not reach a statistical significance. More than 30% of observers disagreed with the reviewer at least in one of the three cases.ConclusionsRECIST measurements are reproducible on a large and heterogeneous population of radiologists. Age and expertise of the radiologist remain the most critical factors: this suggests a revision by well-experienced radiologists in clinical trials.     

Therapy response in malignant pleural mesothelioma-role of MRI using RECIST, modified RECIST and volumetric approaches in comparison with CT

To evaluate and compare early therapy response according to RECIST (response evaluation criteria in solid tumours) and modified RECIST criteria using MRI techniques in patients with malignant pleural mesothelioma (MPM) in comparison with CT. Fifty patients with MPM (32 male/18 female) were included in this study. Early therapy response was evaluated after 9 weeks [three of six chemotherapy (CHT)] cycles. Additionally patients were examined before chemotherapy, 4 weeks after early therapy response evaluation and after six cycles to evaluate diagnostic follow-up. RECIST and modified RECIST criteria were applied using CT and MRI (HASTE, VIBE, T2-TSE sequences). In MRI additionally a volumetric approach measuring tumour weight (overall segmented tumour volume) was applied. Additionally vital capacity (VC) was measured for correlation. Image interpretation was performed by three independent readers independently and in consensus. The 'gold standard' was follow-up examination. Twenty-eight patients showed partial response, 12 patients stable disease and 10 patients progressive disease at early therapy response evaluation. In the follow-up these results remained. For MRI, in 46 cases patients were identically classified using RECIST and modified RECIST criteria. Modified RECIST criteria were identically classified as gold standards in all cases, whereas using RECIST criteria in four cases there was a mismatch (partial response vs. stable disease). Modified RECIST kappa values showed better interobserver variability compared with RECIST criteria (kappa=0.9-1.0 vs. 0.7-1.0). For CT, in 44 cases patients were identically classified using RECIST and modified RECIST criteria. Modified RECIST criteria were identically classified as in gold standards in 48 out of 50 patients, whereas using RECIST criteria in 6 cases there was a mismatch (partial response vs. stable disease). Modified RECIST kappa values showed better interobserver variability compared with RECIST criteria (kappa=0.9-1.0 vs. 0.6-1.0). Modified RECIST criteria especially in combination with high-resolution MRI is a very accurate and reproducible technique to correctly evaluate early therapy response in MPM.     

Exploring intra- and inter-reader variability in uni-dimensional,bi-dimensional,and volumetric measurements of solid tumors on CT scans reconstructed at different slice intervals

Objective

Understanding magnitudes of variability when measuring tumor size may be valuable in improving detection of tumor change and thus evaluating tumor response to therapy in clinical trials and care. Our study explored intra- and inter-reader variability of tumor uni-dimensional (1D), bi-dimensional (2D), and volumetric (VOL) measurements using manual and computer-aided methods (CAM) on CT scans reconstructed at different slice intervals.

Materials and methods

Raw CT data from 30 patients enrolled in oncology clinical trials was reconstructed at 5, 2.5, and 1.25 mm slice intervals. 118 lesions in the lungs, liver, and lymph nodes were analyzed. For each lesion, two independent radiologists manually and, separately, using computer software, measured the maximum diameter (1D), maximum perpendicular diameter, and volume (CAM only). One of them blindly repeated the measurements. Intra- and inter-reader variability for the manual method and CAM were analyzed using linear mixed-effects models and Bland–Altman method.

Results

For the three slice intervals, the maximum coefficients of variation for manual intra-/inter-reader variability were 6.9%/9.0% (1D) and 12.3%/18.0% (2D), and for CAM were 5.4%/9.3% (1D), 11.3%/18.8% (2D) and 9.3%/18.0% (VOL). Maximal 95% reference ranges for the percentage difference in intra-reader measurements for manual 1D and 2D, and CAM VOL were (−15.5%, 25.8%), (−27.1%, 51.6%), and (−22.3%, 33.6%), respectively.

Conclusions

Variability in measuring the diameter and volume of solid tumors, manually and by CAM, is affected by CT slice interval. The 2.5 mm slice interval provides the least measurement variability. Among the three techniques, 2D has the greatest measurement variability compared to 1D and 3D.     

Comparison of Radiological Tumor Response Based on iRECIST and RECIST 1.1 in Metastatic Clear-Cell Renal Cell Carcinoma Patients Treated with Programmed Cell Death-1 Inhibitor Therapy

ObjectiveTo evaluate the radiological tumor response patterns and compare the response assessments based on immune-based therapeutics Response Evaluation Criteria in Solid Tumors (iRECIST) and RECIST 1.1 in metastatic clear-cell renal cell carcinoma (mccRCC) patients treated with programmed cell death-1 (PD-1) inhibitors.Materials and MethodsAll mccRCC patients treated with PD-1 inhibitors at Henan Cancer Hospital, China, between January 2018 and April 2019, were retrospectively studied. A total of 30 mccRCC patients (20 males and 10 females; mean age, 55.6 years; age range, 37–79 years) were analyzed. The target lesions were quantified on consecutive CT scans during therapy using iRECIST and RECIST 1.1. The tumor growth rate was calculated before and after therapy initiation. The response patterns were analyzed, and the differences in tumor response assessments of the two criteria were compared. The intra- and inter-observer variabilities of iRECIST and RECIST 1.1 were also analyzed.ResultsThe objective response rate throughout therapy was 50% (95% confidence interval [CI]: 32.1–67.9) based on iRECIST and 30% (95% CI: 13.6–46.4) based on RECIST 1.1. The time-to-progression (TTP) based on iRECIST was longer than that based on RECIST 1.1 (median TTP: not reached vs. 170 days, p = 0.04). iRECIST and RECIST 1.1 were discordant in 8 cases, which were evaluated as immune-unconfirmed PD based on iRECIST and PD based on RECIST 1.1. Six patients (20%, 6/30) had pseudoprogression based on iRECIST, of which four demonstrated early pseudoprogression and two had delayed pseudoprogression. Significant differences in the tumor response assessments based on the two criteria were observed (p < 0.001). No patients demonstrated hyperprogression during the study period.ConclusionOur study confirmed that the iRECIST criteria are more capable of capturing immune-related atypical responses during immunotherapy, whereas conventional RECIST 1.1 may underestimate the benefit of PD-1 inhibitors. Pseudoprogression is not rare in mccRCC patients during PD-1 inhibitor therapy, and it may last for more than the recommended maximum of 8 weeks, indicating a limitation of the current strategy for immune response monitoring.     

The value of PET, CT and in-line PET/CT in patients with gastrointestinal stromal tumours: long-term outcome of treatment with imatinib mesylate

Purpose Gastrointestinal stromal tumours (GIST) are mesenchymal neoplasms of the gastrointestinal tract that are unresponsive to standard sarcoma chemotherapy. Imaging of GIST patients is done with structural and functional methods such as contrast-enhanced helical computed tomography (ceCT) and positron emission tomography (PET) with ¹⁸F-fluorodeoxyglucose (FDG). The aim of this study was to compare the prognostic power of PET and ceCT and to evaluate the clinical role of PET/CT imaging.Methods All patients with GIST undergoing PET or PET/CT examinations were prospectively included in this study, and the median overall survival, time to progression and treatment duration were documented. The prognostic significance of PET and ceCT criteria of treatment response was assessed and PET/CT was compared with PET and ceCT imaging. Data for 34 patients (19 male, 15 female, 21–76 years) undergoing PET or PET/CT for staging or restaging were analysed.Results In 28 patients, PET/CT and ceCT were available after introduction of treatment with the tyrosine kinase inhibitor imatinib mesylate (Gleevec; Novartis, Basel, Switzerland). Patients without FDG uptake after the start of treatment had a better prognosis than patients with residual activity. In contrast, ceCT criteria provided insufficient prognostic power. However, more lesions were found on ceCT images than on PET images, and FDG uptake was sometimes very variable. PET/CT delineated active lesions better than did the combination of PET and ceCT imaging.Conclusion Both PET and PET/CT provide important prognostic information and have an impact on clinical decision-making in GIST patients. PET/CT precisely delineates lesions and thus allows for the correct planning of surgical interventions.     

Automated CT volumetry of pulmonary metastases: the effect of a reduced growth threshold and target lesion number on the reliability of therapy response assessment using RECIST criteria

The purpose of this study was to evaluate the reproducibility of CT-volumetric tumour response assessment of pulmonary metastasis using variable volume change thresholds (VCT) and target lesions with response evaluation criteria in solid tumours (RECIST). Fifty consecutive patients with pulmonary metastases undergoing follow-up multislice CT under chemotherapy were assessed for response to chemotherapy with modifications to RECIST: (1) decreasing the percentual VCT for diagnosis of tumour response (range = 70%–20%), (2) reducing the number of target lesions (range = 1–5). Continuous and categorical observer agreements were tested by Bland and Altman and extended (κ_e) or non-weighted kappa (κ) and correlated with percentual VCT to predict observer agreement. A total of 202 metastases were evaluated (average volume = 522.4 mm³±902.4 mm³). General agreement on treatment response was very high (κ_e = 0.93–1), but was reduced with VCT < 35% (κ_e < 0.95). Kappa correlation with VCT values was strong (r=0.94–0.96; p≤0.0002). Average confidence decreased significantly at VCT < 45% (p < 0.01) and agreement on stable disease at VCT < 35% (κ_e < 0.95; p < 0.01). Reduction of target lesions (n < 3; VCT = 35%) resulted in decreased reader confidence (for n = 1: κ = 0.49; p < 0.05). Agreement for evaluation of treatment response was robust using VCT ≥35% and ≥3 metastases. This may translate into shortening of follow-up intervals or enable for response assessment with tumours displaying minimal volume change.     

胃肠道间质瘤的CT和MRI诊断价值(附16例分析)

目的:评价CT和MRI诊断胃肠道间质瘤的价值。方法:回顾性分析经手术和病理证实的16例胃肠道间质瘤患者的资料。结果:16例肿瘤均为单发,位于胃部9例,空肠3例,回肠、食管、直肠及后腹膜各1例。良性2例,潜在恶性4例,恶性10例。CT和MRI表现:粘膜下富血供性肿块,肿瘤倾向于腔外生长,可有囊变、坏死、出血、钙化。增强后良性者强化均匀,边界清楚,恶性者强化不均匀,可有邻近结构侵犯。结论:CT和MRI对胃肠道间质瘤的定位和定性判断,以及鉴别诊断有重要价值。     

Perfusion CT in acute stroke: prediction of vessel recanalization and clinical outcome in intravenous thrombolytic therapy

This study evaluated perfusion computed tomography (PCT) for the prediction of vessel recanalization and clinical outcome in patients undergoing intravenous thrombolysis. Thirty-nine patients with acute ischemic stroke of the middle cerebral artery territory underwent intravenous thrombolysis within 3 h of symptom onset. They all had non-enhanced CT (NECT), PCT, and CT angiography (CTA) before treatment. The Alberta Stroke Program Early Computed Tomography (ASPECT) score was applied to NECT and PCT maps to assess the extent of ischemia. CTA was assessed for the site of vessel occlusion. The National Institute of Health Stroke Scale (NIHSS) score was used for initial clinical assessment. Three-month clinical outcome was assessed using the modified Rankin scale. Vessel recanalization was determined by follow-up ultrasound. Of the PCT maps, a cerebral blood volume (CBV) ASPECT score of >6 versus ≤6 was the best predictor for clinical outcome (odds ratio, 31.43; 95% confidence interval, 3.41–289.58; P < 0.002), and was superior to NIHSS, NECT and CTA. No significant differences in ASPECT scores were found for the prediction of vessel recanalization. ASPECT score applied to PCT maps in acute stroke patients predicts the clinical outcome of intravenous thrombolysis and is superior to both early NECT and clinical parameters. S.P. Kloska and R. Dittrich contributed equally to this work.     

Follow-up of hepatic and peritoneal metastases of gastrointestinal tumors (GIST) under Imatinib therapy requires different criteria of radiological evaluation (size is not everything!!!)

Purpose

To define computed tomography (CT) criteria for evaluating the response of patients with gastrointestinal stromal tumors (GIST) who are receiving Imatinib (tyrosine-kinase inhibitor therapy).

Materials and methods

This prospective CT study evaluated 107 consecutive patients with advanced metastatic GIST treated with Imatinib.

Results

Seventy patients had total or partial cystic-like transformation of hepatic and/or peritoneal metastases. These pseudocysts remained unchanged in size or stable in size on successive CT examinations (stable disease according to RECIST criteria). Forty-six patients developed metastases, 17 patients showed increasing parietal thickness and 29 patients with peripheral enhancing nodules. These CT changes represented local recurrence consistent with GIST resistance to Imatinib treatment. WHO or RECIST criteria did not provide a reliable evaluation of disease evolution or recurrence. Development of new enhancement of lesions (parietal thickness or nodule) was the only reliable criterion.

Conclusion

The development of peripheral thickening or enhancing nodules within cystic-like metastatic lesions, even without any change in size, represented progressive GIST under Imatinib, growing in a short time and should alert the clinician for the possible need for a change in therapy.     

Imaging-Based Tumor Treatment Response Evaluation: Review of Conventional, New, and Emerging Concepts

Tumor response may be assessed readily by the use of Response Evaluation Criteria in Solid Tumor version 1.1. However, the criteria mainly depend on tumor size changes. These criteria do not reflect other morphologic (tumor necrosis, hemorrhage, and cavitation), functional, or metabolic changes that may occur with targeted chemotherapy or even with conventional chemotherapy. The state-of-the-art multidetector CT is still playing an important role, by showing high-quality, high-resolution images that are appropriate enough to measure tumor size and its changes. Additional imaging biomarker devices such as dual energy CT, positron emission tomography, MRI including diffusion-weighted MRI shall be more frequently used for tumor response evaluation, because they provide detailed anatomic, and functional or metabolic change information during tumor treatment, particularly during targeted chemotherapy. This review elucidates morphologic and functional or metabolic approaches, and new concepts in the evaluation of tumor response in the era of personalized medicine (targeted chemotherapy).     

Differentiation of large (≥5 cm) gastrointestinal stromal tumors from benign subepithelial tumors in the stomach: Radiologists’ performance using CT

Purpose

To identify significant CT findings for the differentiation of large (≥5 cm) gastric gastrointestinal stromal tumors (GIST) from benign subepithelial tumors and to assess whether radiologists’ performance in differentiation is improved with knowledge of significant CT criteria.

Materials and methods

One-hundred twenty patients with pathologically proven large (≥5 cm) GISTs (n = 99), schwannomas (n = 16), and leiomyomas (n = 5) who underwent CT were enrolled. Two radiologists (A and B) retrospectively reviewed their CT images in consensus for the location, size, degree and pattern of enhancement, contour, growth pattern and the presence of calcification, necrosis, surface ulceration, or enlarged lymph nodes. CT findings considered significant for differentiation were determined using uni- and multivariate statistical analyses. Thereafter, two successive review sessions for the differentiation of GIST from non-GIST were independently performed by two other reviewers (C and D) with different expertise of 2 and 9 years using a 5-point confidence scale. At the first session, reviewers interpreted CT images without knowledge of significant CT findings. At the second session, the results of statistical analyses were provided to the reviewers. To assess improvement in radiologists’ performance, a pairwise comparison of receiver operating curves (ROC) was performed.

Results

Heterogeneous enhancement, presence of necrosis, absence of lymph nodes, and mean size of ≥6 cm were found to be significant for differentiating GIST from schwannoma (P < 0.05). Non-cardial location, heterogeneous enhancement, and presence of necrosis were differential CT features of GIST from leiomyoma (P < 0.05). Multivariate analyses indicated that absence of enlarged LNs was the only statistically significant variable for GIST differentiating from schwannoma. The area under the curve of both reviewers obtained using ROC significantly increased from 0.682 and 0.613 to 0.903 and 0.904, respectively, with information of the significant CT findings differentiating GISTs from non-GISTs (P < 0.001).

Conclusion

Non-cardial location, heterogeneous enhancement, presence of necrosis, larger lesion size, and absence of lymphadenopathy are highly suggestive CT findings for large GISTs in differentiation from schwannomas or leiomyomas. Regardless of radiologists’ expertise, diagnostic performance in differentiation can be significantly improved with knowledge of these CT findings.     

实体瘤反应评价标准、欧洲肝病学会和改良实体瘤反应评价标准评价原发性肝癌化疗栓塞效果一致性的比较

目的 比较实体瘤反应评价标准(RECIST)、欧洲肝病学会(EASL)和改良的RECIST标准用于评价原发性肝癌化疗栓塞术后肿瘤缓解程度的一致性.方法 50例确诊为原发性肝癌患者接受两次化疗栓塞术.术前1周内、治疗后4周患者分别接受螺旋CT或MR三期扫描.据RECIST、EASL、改良RECIST标准评价肿瘤缓解程度.3种方法评价缓解率的比较采用x2检验,一致性检验采用kappa分析.结果 据RECIST、EASL、改良RECIST标准分别评价疗效时,达CR、PR、SD、PD患者例数分别为0、10、30、10例,6、21、14、9例,6、21、13、10例.据上述3种标准评价治疗的缓解率分别为20%、54%、54%,差异有统计学意义(P＜0.01).RECIST与EASL标准之间、RECIST与改良RECIST标准之间的kappa分析,kappa值分别为0.382、0.170(P=0.000);而EASL与改良RECIST标准之间的kappa值达0.857(P=0.000).结论 RECIST标准低估原发性肝癌化疗栓塞术局部治疗的效果.EASL和改良RECIST标准,对疗效评价一致性程度高;但改良RECIST标准在临床实践中更简便易行.     

Comparison between CT volume measurement and histopathological assessment of response to neoadjuvant therapy in rectal cancer

Objectives

The aim of this study was to compare volume measurements on computed tomography (CT) images with histopathological assessments of chemoradiotherapy (CRT)-induced tumor regression in locally advanced rectal cancer (RC).

Methods

In 25 patients (13 males, 12 females; median age, 63 years; age range, 44–79 years) with locally advanced RC treated with preoperative CRT and surgery, two radiologists measured tumor volume on CT images before and after CRT. CT-based tumor volumetry and the modified response evaluation criteria in solid tumors (mRECISTs) were compared with T and N downstaging after CRT, and with the tumor regression grade (TRG).

Results

Tumor volumes were significantly smaller on CT images after CRT. The tumors regressed in 52% (13/25), 36% (9/25) and 40% (10/25) of patients, based on T downstaging, TRG and mRECIST findings, respectively. In terms of T downstaging, the pre- and post-CRT tumor volumes of responders and non-responders to the treatment differed statistically, while their tumor volume reduction rates and volume reductions according to the 65% mRECIST threshold did not. In terms of N downstaging and TRG, the differences between the responders’ and the non-responders’ pre- and post-CRT tumor volumes, tumor volume reduction rates, and mRECIST thresholds were never statistically significant.

Conclusion

Measuring tumor size on CT images is of limited value in predicting the histopathological response to preoperative CRT in RC patients, so it may be unwise to select surgical treatment strategies based on CT volumetry.     

Radiomics and its emerging role in lung cancer research,imaging biomarkers and clinical management: State of the art

With the development of functional imaging modalities we now have the ability to study the microenvironment of lung cancer and its genomic instability. Radiomics is defined as the use of automated or semi-automated post-processing and analysis of large amounts of quantitative imaging features that can be derived from medical images. The automated generation of these analytical features helps to quantify a number of variables in the imaging assessment of lung malignancy. These imaging features include: tumor spatial complexity, elucidation of the tumor genomic heterogeneity and composition, subregional identification in terms of tumor viability or aggressiveness, and response to chemotherapy and/or radiation. Therefore, a radiomic approach can help to reveal unique information about tumor behavior. Currently available radiomic features can be divided into four major classes: (a) morphological, (b) statistical, (c) regional, and (d) model-based. Each category yields quantitative parameters that reflect specific aspects of a tumor. The major challenge is to integrate radiomic data with clinical, pathological, and genomic information to decode the different types of tissue biology. There are many currently available radiomic studies on lung cancer for which there is a need to summarize the current state of the art.     

Pulmonary cryptococcosis in rheumatoid arthritis (RA) patients: Comparison of imaging characteristics among RA,acquired immunodeficiency syndrome,and immunocompetent patients

Purpose

The imaging characteristics of cryptococcosis in rheumatoid arthritis (RA) patients were analyzed by comparing them with those of acquired immunodeficiency syndrome (AIDS) and immunocompetent patients, and the imaging findings were correlated with pathological findings.

Methods

Two radiologists retrospectively compared the computed tomographic (CT) findings of 35 episodes of pulmonary cryptococcosis in 31 patients with 3 kinds of underlying states (10 RA, 12 AIDS, 13 immunocompetent), focusing on the nature, number, and distribution of lesions. The pathological findings of 18 patients (8 RA, 2 AIDS, 8 immunocompetent) were analyzed by two pathologists, and then correlated with imaging findings.

Results

The frequencies of consolidation and ground glass attenuation (GGA) were significantly higher, and the frequency of peripheral distribution was significantly lower in the RA group than in the immunocompetent group. Peripheral distribution was less common and generalized distribution was more frequent in the RA group than in the AIDS group. The pathological findings of the AIDS and immunocompetent groups reflected their immune status: There was lack of a granuloma reaction in the AIDS group, and a complete granuloma reaction in the immunocompetent group, while the findings of the RA group varied, including a complete granuloma reaction, a loose granuloma reaction and a hyper-immune reaction. Cases with the last two pathologic findings were symptomatic and showed generalized or central distribution on CT.

Conclusion

Cryptococcosis in the RA group showed characteristic radiological and pathological findings compared with the other 2 groups.