Adrenal mass imaging with multidetector CT: pathologic conditions, pearls, and pitfalls

Early stage adrenocortical carcinoma-what contributes to poor prognosis after adrenalectomy? A retrospective cohort study

Purpose

Adrenocortical carcinoma (ACC) is a rare primary carcinoma originating in the adrenal gland with a poor prognosis and a high recurrence rate. This study evaluated the risk factors associated with recurrence in patients with early stage ACC after curative surgical resection.

Methods

The present study retrospectively evaluated the risk factors for recurrence in 38 patients with stages 1 and 2 ACC who underwent curative resection between 1995 and 2020.

Results

Recurrence was observed in 21 patients (55.3%), with no significant difference between stages 1 and 2 ACC (P = 0.640). The overall recurrence rate was higher in patients who underwent minimally invasive surgery than open adrenalectomy (71.4% vs. 51.6%). Of the 33 patients with gross tumor margins negative for malignancy, 16 (48.5%) experienced tumor recurrence, and all 5 patients with positive and unknown gross resection margins had recurrence. Recurrences were observed in 14 of the 30 patients (46.7%) negative for pathologic resection margins, 6 of the 7 patients (85.7%) with pathologically indeterminate margins, and 1 patient with pathologically positive margins.

Conclusion

The recurrence rates are high even in patients with early stage ACC, being higher in patients who undergo minimally invasive surgery than open adrenalectomy. Obtaining clear resection margins during surgery may reduce tumor recurrence; however, gross or pathologic margin safety was not a secure factor in preventing recurrence. None of the factors analyzed was a definitive predictor of poor prognosis.

Validation of the modified CT criteria for identifying non-adenomas

PURPOSE

Although adrenal computed tomography (CT) percentage washout is a potentially powerful imaging technique for differentiating adrenal adenomas from non-adenomas, its application to non-adenomas can be problematic. Recently, modified criteria for diagnosing pheochromocytomas using adrenal CT were developed based on data from 199 patients with surgically proven pheochromocytomas and adenomas. However, these criteria have not been thoroughly validated. The purpose of this study was to validate the performance of the modified criteria for diagnosing non-adenomas including pheochromocytomas.

METHODS

The conventional and modified criteria were applied to 266 patients from two cohorts who had surgically proven lipid-poor adenomas (155/266, 58.3%) and non-adenomas (111/266, 41.7%) and underwent adrenal CT. Two radiologists calculated the attenuation on each dynamic phase and percentage washout of adrenal masses. The final assessments based on the conventional and modified criteria were categorized into adenomas or non-adenomas. The diagnostic performance of each criterion for diagnosing non-adenomas was evaluated using the area under the receiver operating characteristic curve (AUC). False negatives and positives were also compared.

RESULTS

The AUC for the diagnosis of non-adenomas was 0.806 for conventional criteria and 0.858 for modified criteria (p = 0.047). The false-negative rate of conventional criteria for the diagnosis of non-adenomas was 29.7%. Use of modified criteria could have reduced the false-negative rate by to 7.2%. The false-positive rate increased from 9% to 21.3% when using the modified criteria.

CONCLUSION

The utilization of modified criteria has the potential to identify additional non-adenomas that would otherwise be misdiagnosed as adenomas using conventional criteria alone.

MCNet: A multi-level context-aware network for the segmentation of adrenal gland in CT images

Accurate segmentation of the adrenal gland from abdominal computed tomography (CT) scans is a crucial step towards facilitating the computer-aided diagnosis of adrenal-related diseases such as essential hypertension and adrenal tumors. However, the small size of the adrenal gland, which occupies less than 1% of the abdominal CT slice, poses a significant challenge to accurate segmentation. To address this problem, we propose a novel multi-level context-aware network (MCNet) to segment adrenal glands in CT images. Our MCNet mainly consists of two components, i.e., the multi-level context aggregation (MCA) module and multi-level context guidance (MCG) module. Specifically, the MCA module employs multi-branch dilated convolutional layers to capture geometric information, which enables handling of changes in complex scenarios such as variations in the size and shape of objects. The MCG module, on the other hand, gathers valuable features from the shallow layer and leverages the complete utilization of feature information at different resolutions in various codec stages. Finally, we evaluate the performance of the MCNet on two CT datasets, including our clinical dataset (Ad-Seg) and a publicly available dataset known as Distorted Golden Standards (DGS), from different perspectives. Compared to ten other state-of-the-art segmentation methods, our MCNet achieves 71.34% and 75.29% of the best Dice similarity coefficient on the two datasets, respectively, which is at least 2.46% and 1.19% higher than other segmentation methods.

Three-dimensional CT cinematic rendering of adrenal masses: Role in tumor analysis and management

The adrenal gland is home to an array of complex physiological and neoplastic disease processes. While dedicated adrenal computed tomography (CT) is the gold standard imaging modality for adrenal lesions, there exists significant overlap among imaging features of adrenal pathology. This can often make radiological diagnosis and subsequent determination of the optimal surgical approach challenging. Cinematic rendering (CR) is a novel CT post-processing technique that utilizes advanced light modeling to generate highly photorealistic anatomic visualization. This generates unique prospects in the evaluation of adrenal masses. As one of the first large tertiary care centers to incorporate CR into routine diagnostic workup, our preliminary experience with using CR has been positive, and we have found CR to be a valuable adjunct during surgical planning. Herein, we highlight the unique utility of CR techniques in the workup of adrenal lesions and provide commentary on the opportunities and obstacles associated with the application of this novel display method in this setting.

Can MDCT Enhancement Patterns Be Helpful in Differentiating Secretory from Non-Functional Adrenal Adenoma?

Background and Objectives: Primary adrenal tumors (AT) are a heterogeneous group of neoplasms due to their functional heterogeneity, which results in the diverse clinical presentation of these tumors. The purpose of this study was to examine cross-sectional imaging characteristics using multi-detector computed tomography (MDCT) to provide insight into the lesion characterization and functional status of these tumors. The radionuclide imaging using Technetium-99m radiolabeled hydrazinonicotinylacid-d-phenylalanyl1-tyrosine3-octreotide (99mTc-HYNIC-TOC), was also used in the diagnostic evaluation of these tumors. Materials and Methods: This cross-sectional study included 50 patients with confirmed diagnoses of AT (21 hormone-secreting and 29 non-functional) at the University Clinical Center, Kragujevac, Serbia, during the 2019-2022 year period. The morphological and dynamic characteristics using MDCT were performed, using qualitative, semi-quantitative, and quantitative analysis. Absolute washout (APW) and relative washout (RPW) values were also calculated. A semi-quantitative analysis of all visual findings with 99mTc-HYNIC-TOC was performed to compare the tumor to non-tumor tracer uptake. Results: A statistically significant difference was found in the MDCT values in the native phase (p < 0.05), the venous phase (p < 0.05), and the delayed phase (p < 0.001) to detect the existence of adrenal tumors. Most of these functional adrenocortical lesions (n = 44) can be differentiated using the delayed phase (p < 0.05), absolute percentage washout (APW) (p < 0.05), and relative percentage washout (RPW) (p < 0.001). Furthermore, 99mTc-HYNIC-TOC could have a high diagnostic yield to detect adrenal tumor existence (p < 0.001). There is a positive correlation between radionuclide imaging scan and APW to detect all AT (p < 0.01) and adrenocortical adenomas as well (p < 0.01). Conclusions: The results can be very helpful in a diagnostic algorithm to quickly and precisely diagnose the expansive processes of the adrenal glands, as well as to learn about the advantages and limitations of the mentioned imaging modalities.

Adrenal Abscess in a Chronic Hemodialysis Patient: A Case Report

Adrenal gland abscesses are rare lesions usually reported to be caused by fungal pathogens and typically through hematogenous spread from other primary sources of infection. Imaging has always been known to play a major role in the characterization of focal adrenal lesions. However, given the rare occurrence of abscesses in this location, making the right diagnosis remains challenging. We report the case of a 39-year-old man with chronic renal disease on hemodialysis presenting with signs of sepsis and left upper quadrant pain revealing a left adrenal gland abscess.

The Use of Ovarian Vein Sampling to Lateralize a Virilizing Leydig Cell Ovarian Tumor

Background/Objective

Leydig cell tumors are a rare androgen-secreting ovarian tumor. We present a patient with virilization symptoms secondary to a Leydig cell tumor, with nonrevealing imaging studies, that was localized using ovarian vein sampling (OVS).

Case Report

A 56-year-old postmenopausal woman was referred by her gynecologist to the endocrinology clinic for voice-deepening, clitoral enlargement, scalp hair loss, and excessive body hair growth. Her total testosterone was 11.5 (0.3-1.3 nmol/L), bioavailable testosterone was 7.19 (0.1-0.6 nmol/L), and dehydroepiandrosterone sulfate was 4.0 (0.8-4.9 μmol/L). Transvaginal ultrasound and abdominal magnetic resonance imaging showed no adrenal or ovarian masses bilaterally. On adrenal vein sampling (AVS) and OVS, total testosterone from the left gonadal vein was 780.0 (0.3-1.3 nmol/L) and right gonadal vein was 18.6 (0.3-1.3 nmol/L), with a left-to-right ovarian testosterone ratio of 41.94. A bilateral salpingo-oophorectomy was performed, and a 1.0 cm Leydig cell tumor in the left ovary was noted on histopathology. One month after surgery, her total and bioavailable testosterone were <0.4 (0.3-1.3 nmol/L and 0.1-0.6 nmol/L, respectively). At 6 months, she had normalization of her voice to baseline, decreased clitoral size, decreased hair growth on her back, and improvement in her male-pattern baldness.

Discussion

OVS and AVS are useful diagnostic investigation tools in cases of virilization, in which imaging is nonrevealing. Our case supports previously suggested left-to-right ovarian vein testosterone ratio of ≥15 being associated with a left-sided tumor.

Conclusion

Few cases have been published on the interpretation of AVS and OVS in the setting of virilization. Previously suggested ratios for lateralization were valid for this patient.

Role of computed tomography in predicting adrenal adenomas with cortisol hypersecretion

OBJECTIVES

To investigate performance of adrenal CT-derived multivariate prediction models in differentiating adenomas with cortisol hypersecretion from the other subtypes.

METHODS

This retrospective study included 127 patients who underwent adrenal CT and had a surgically proven adrenal adenoma. Adenoma subtypes were defined according to biochemical test results: Group A, overt cortisol hypersecretion; Group B, mild cortisol hypersecretion; Group C, aldosterone hypersecretion; and Group D, non-function. Two independent readers analyzed size, attenuation, and washout properties of adenomas, and performed quantitative and qualitative analyses for assessing contralateral adrenal atrophy. Actual and internally validated areas under the curves (AUCs) of adrenal CT-derived multivariate prediction models for differentiating adenomas with cortisol hypersecretion from the other subtypes were assessed.

RESULTS

In differentiating Group A from the other groups, the actual and internally validated AUCs of the prediction model were 0.856 (95% confidence interval [CI]: 0.786, 0.926) and 0.847 (95% CI: 0.695, 0.999) for Reader 1, respectively, and 0.901 (95% CI: 0.845, 0.956) and 0.897 (95% CI: 0.783, 1.000) for Reader 2, respectively. In differentiating Group B from groups C and D, the actual and internally validated AUCs of the prediction model were 0.777 (95% CI: 0.687, 0.866) and 0.760 (95% CI: 0.552, 0.969) for Reader 1, respectively, and 0.783 (95% CI: 0.690, 0.875) and 0.765 (95% CI: 0.553, 0.977) for Reader 2, respectively.

CONCLUSION

Adrenal CT may be useful in differentiating adenomas with cortisol hypersecretion from the other subtypes.

ADVANCES IN KNOWLEDGE

Adrenal CT may benefit in adrenal adenoma subtyping.

Impact of body weight and sex in selected dog breeds on the canine adrenal gland dimensions measured by computed tomographic imaging

BACKGROUND

The present study aimed to investigate possible influences of body weight and sex on adrenal gland size in endocrinologically healthy dogs. Possible factors influencing the adrenal size are discussed in relation to a universal upper reference value from the literature of 7.4 mm as the thickness in the caudal pole of the adrenal gland. The adrenal size was measured by computed tomography (CT) from 66 normal dogs of six different breeds (Labrador Retriever (n = 16), German Shepherd (n = 10), Boxer (n = 8), Beagle (n = 14), Dachshund (n = 6) and Jack Russell Terrier (n = 12); male n = 38 (thereof neutered n = 23), female n = 28 (thereof neutered n = 17)) based on volume quantification and linear measurements using the data processing software Amira. For interbreed comparability, a ratio consisting of the third root of adrenal volume to aortic diameter (Ratio volume-aorta, RVA) was introduced. Additionally, breed-related attenuation values in contrast-enhanced CT data sets were measured.

RESULTS

The measured volumes ranged from 0.34 to 1.93 cm3 for the right and from 0.39 to 2.23 cm3 for the left adrenal gland. The present study was able to demonstrate a body weight effect on the adrenal volume as well as on length and height. In terms of adrenal size, no significant differences between male and female, nor between intact and neutered dogs were obtained due to the RVA. In addition, for the weight classes, a breed independent threshold for dogs less (left 1.4; right gland 1.5) or more than 20 kg body weight (left 1.1; right gland 1.2) based on RVA was defined. Breed-related significant differences with respect to attenuation were determined only for the left adrenal gland, with lower attenuation values in large dog breeds.

CONCLUSION

The present study points out the importance of weight-related data when assessing CT data of the canine adrenal gland regarding volume, size and attenuation. The use of a universal reference value for the assessment of adrenal size appears unsuitable considering weight-related volume and linear measurements. Sex seems not to affect adrenal gland size.

Adrenal Abscesses: A Systematic Review of the Literature

Objective: To summarize the existing knowledge about adrenal gland abscesses, including etiology, clinical presentation, common laboratory and imaging findings, management and overall morbidity and mortality. Design: Systematic literature review. Methods: We performed a search in the PubMed database using search terms: 'abscess and adrenal glands', 'adrenalitis', 'infection and adrenal gland', 'adrenal abscess', 'adrenal infection' and 'infectious adrenalitis'. Articles from 2017 to 2022 were included. We found total of 116 articles, and after applying exclusion criteria, data from 73 articles was included in the final statistical analysis. Results: Of 84 patients included in this review, 68 were male (81%), with a mean age of 55 years (range: 29 to 85 years). Weight loss was the most frequent symptom reported in 58.3% patients, followed by fever in 49%. Mean duration of symptoms was 4.5 months. The most common laboratory findings were low cortisol (51.9%), elevated ACTH (43.2%), hyponatremia (88.2%) and anemia (83.3%). Adrenal cultures were positive in 86.4% cases, with Histoplasma capsulatum (37.3%) being the leading causative agent. Blood cultures were positive in 30% of patients. The majority of the adrenal infections occurred through secondary dissemination from other infectious foci and abscesses were more commonly bilateral (70%). A total of 46.4% of patients developed long-term adrenal insufficiency requiring treatment. Abscess drainage was performed in 7 patients (8.3%) and adrenalectomy was performed in 18 (21.4%) patients. The survival rate was 92.9%. Multivariate analysis showed that the only independent risk factor for mortality was thrombocytopenia (p = 0.048). Conclusion: Our review shows that adrenal abscesses are usually caused by fungal pathogens, and among these, Histoplasma capsulatum is the most common. The adrenal glands are usually involved in a bilateral fashion and become infected through dissemination from other primary sources of infection. Long-term adrenal insufficiency develops in 46% of patients, which is more common than what is observed in non-infectious etiology of adrenal gland disorders. Mortality is about 7%, and the presence of thrombocytopenia is associated with worse prognosis. Further prospective studies are needed to better characterize optimal testing and treatment duration in patients with this relatively rare but challenging disorder.

Age-related morphometrics of normal adrenal glands based on deep learning-aided segmentation

OBJECTIVE

This study aims to evaluate the morphometrics of normal adrenal glands in adult patients semiautomatically using a deep learning-based segmentation model.

MATERIALS AND METHODS

A total of 520 abdominal CT image series with normal findings, from January 1, 2016, to March 14, 2019, were retrospectively collected for the training of the adrenal segmentation model. Then, 1043 portal venous phase image series of inpatient contrast-enhanced abdominal CT examinations with normal adrenal glands were included for analysis and grouped by every 10-year gap. A 3D U-Net-based segmentation model was used to predict bilateral adrenal labels followed by manual modification of labels as appropriate. Quantitative parameters (volume, CT value, and diameters) of the bilateral adrenal glands were then analyzed.

RESULTS

In the study cohort aged 18-77 years old (554 males and 489 females), the left adrenal gland was significantly larger than the right adrenal gland [all patients, 2867.79 (2317.11-3499.89) mm³ vs. 2452.84 (1983.50-2935.18) mm³, P < 0.001]. Male patients showed a greater volume of bilateral adrenal glands than females in all age groups (all patients, left: 3237.83 ± 930.21 mm³ vs. 2646.49 ± 766.42 mm³, P < 0.001; right: 2731.69 ± 789.19 mm³ vs. 2266.18 ± 632.97 mm³, P = 0.001). Bilateral adrenal volume in male patients showed an increasing then decreasing trend as age increased that peaked at 38-47 years old (left: 3416.01 ± 886.21 mm³, right: 2855.04 ± 774.57 mm³).

CONCLUSIONS

The semiautomated measurement revealed that the adrenal volume differs as age increases. Male patients aged 38-47 years old have a peaked adrenal volume.

CT of hemorrhagic adrenal adenomas: radiologic-pathologic correlation

PURPOSE

To describe the appearance of chronically hemorrhagic adenomas on adrenal protocol CT and correlate imaging with pathologic findings.

METHODS

Retrospective case series of adult patients with resected adrenal adenomas showing internal hemorrhage at histology. Seven of nine patients underwent pre-operative adrenal protocol CT and 2/7 underwent unenhanced CT with portal venous phase CT. Two abdominal radiologists in consensus assessed the CT images for the presence of calcifications, macroscopic fat, cystic/necrotic appearance, and the presence, pattern, and percent nodule volume of areas < 10 HU on unenhanced CT. Absolute washout was calculated using a large ROI, and ROIs on the highest and lowest attenuating regions on the portal venous phase.

RESULTS

Mean adenoma length was 4.9 cm. All adenomas had areas measuring < 10 HU on unenhanced CT, ranging from < 20 to > 80% nodule volume. Calcifications were present in 4/9 adenomas and gross fat in 4/9 on CT. Of the seven cases with adrenal protocol CT, the absolute washout was < 60% in 5/7 using the large ROI, 5/7 using the low attenuation ROI, and 7/7 using the high attenuation ROI. At histology, all nine cases had microscopic evidence of hemorrhage, lipid rich adenoma cells, and fibrosclerosis. Myelolipomatous changes were identified in 4/9 cases, with the remaining five cases showing lipomatous metaplasia without a myeloid component.

CONCLUSION

Chronically hemorrhagic adrenal adenomas demonstrated variable areas < 10 HU on unenhanced CT corresponding to lipid rich adenoma cells. Absolute washout was most often < 60%, hypothesized to be due to fibrosclerosis within the adenomas.

Adrenal Lesions: A Review of Imaging

Adrenal lesions are frequently incidentally diagnosed during investigations for other clinical conditions. Despite being usually benign, nonfunctioning, and silent, they can occasionally cause discomfort or be responsible for various clinical conditions due to hormonal dysregulation; therefore, their characterization is of paramount importance for establishing the best therapeutic strategy. Imaging techniques such as ultrasound, computed tomography, magnetic resonance, and PET-TC, providing anatomical and functional information, play a central role in the diagnostic workup, allowing clinicians and surgeons to choose the optimal lesion management. This review aims at providing an overview of the most encountered adrenal lesions, both benign and malignant, including describing their imaging characteristics.

Diagnostic performance of radiomics in adrenal masses: A systematic review and meta-analysis

Objectives

(1) To assess the methodological quality and risk of bias of radiomics studies investigating the diagnostic performance in adrenal masses and (2) to determine the potential diagnostic value of radiomics in adrenal tumors by quantitative analysis.

Methods

PubMed, Embase, Web of Science, and Cochrane Library databases were searched for eligible literature. Methodological quality and risk of bias in the included studies were assessed by the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) and Radiomics Quality Score (RQS). The diagnostic performance was evaluated by pooled sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC). Spearman’s correlation coefficient and subgroup analysis were used to investigate the cause of heterogeneity. Publication bias was examined using the Deeks’ funnel plot.

Results

Twenty-eight studies investigating the diagnostic performance of radiomics in adrenal tumors were identified, with a total of 3579 samples. The average RQS was 5.11 (14.2% of total) with an acceptable inter-rater agreement (ICC 0.94, 95% CI 0.93–0.95). The risk of bias was moderate according to the result of QUADAS-2. Nine studies investigating the use of CT-based radiomics in differentiating malignant from benign adrenal tumors were included in the quantitative analysis. The pooled sensitivity, specificity, DOR and AUC with 95% confidence intervals were 0.80 (0.68-0.88), 0.83 (0.73-0.90), 19.06 (7.87-46.19) and 0.88 (0.85–0.91), respectively. There was significant heterogeneity among the included studies but no threshold effect in the meta-analysis. The result of subgroup analysis demonstrated that radiomics based on unenhanced and contrast-enhanced CT possessed higher diagnostic performance, and second-order or higher-order features could enhance the diagnostic sensitivity but also increase the false positive rate. No significant difference in diagnostic ability was observed between studies with machine learning and those without.

Conclusions

The methodological quality and risk of bias of studies investigating the diagnostic performance of radiomics in adrenal tumors should be further improved in the future. CT-based radiomics has the potential benefits in differentiating malignant from benign adrenal tumors. The heterogeneity between the included studies was a major limitation to obtaining more accurate conclusions.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/ CRD 42022331999 .

A deep learning-based approach for the diagnosis of adrenal adenoma: a new trial using CT

OBJECTIVE

To develop and validate deep convolutional neural network (DCNN) models for the diagnosis of adrenal adenoma (AA) using CT.

METHODS

This retrospective study enrolled 112 patients who underwent abdominal CT (non-contrast, early, and delayed phases) with 107 adrenal lesions (83 AAs and 24 non-AAs) confirmed pathologically and with 8 lesions confirmed by follow-up as metastatic carcinomas. Three patients had adrenal lesions on both sides. We constructed six DCNN models from six types of input images for comparison: non-contrast images only (Model A), delayed phase images only (Model B), three phasic images merged into a 3-channel (Model C), relative washout rate (RWR) image maps only (Model D), non-contrast and RWR maps merged into a 2-channel (Model E), and delayed phase and RWR maps merged into a 2-channel (Model F). These input images were prepared manually with cropping and registration of CT images. Each DCNN model with six convolutional layers was trained with data augmentation and hyperparameter tuning. The optimal threshold values for binary classification were determined from the receiver-operating characteristic curve analyses. We adopted the nested cross-validation method, in which the outer fivefold cross-validation was used to assess the diagnostic performance of the models and the inner fivefold cross-validation was used to tune hyperparameters of the models.

RESULTS

The areas under the curve with 95% confidence intervals of Models A-F were 0.94 [0.90, 0.98], 0.80 [0.69, 0.89], 0.97 [0.94, 1.00], 0.92 [0.85, 0.97], 0.99 [0.97, 1.00] and 0.94 [0.86, 0.99], respectively. Model E showed high area under the curve greater than 0.95.

CONCLUSION

DCNN models may be a useful tool for the diagnosis of AA using CT.

ADVANCES IN KNOWLEDGE

The current study demonstrates a deep learning-based approach could differentiate adrenal adenoma from non-adenoma using multiphasic CT.

Prognosis and Therapeutic Efficacy Prediction of Adrenocortical Carcinoma Based on a Necroptosis-Associated Gene Signature

Background. Adrenocortical carcinoma (ACC) is a rare and poor prognosis malignancy. Necroptosis is a special type of cell apoptosis, which is regulated in caspase-independent pathways and mainly induced through the activation of receptor-interacting protein kinase 1, receptor-interacting protein kinase 3, and mixed lineage kinase domain-like pseudokinase. A precise predictive tool based on necroptosis is needed to improve the level of diagnosis and treatment. Method. Four ACC cohorts were enrolled in this study. The Cancer Genome Atlas ACC (TCGA-ACC) cohort was used as the training cohort; three datasets (GSE19750, GSE33371, and GSE49278) from Gene Expression Omnibus (GEO) platform were combined as the GEO testing cohort after removing of batch effect. Forty-nine necroptosis-associated genes were obtained from a prior study and further filtered by least absolute shrinkage and selection operator Cox regression analysis; corresponding coefficients were used to calculate the necroptosis-associated gene score (NAGs). Patients in the TCGA-ACC cohort were equally divided into two groups with the mean value of NAGs. We investigated the associations between NAGs groups and clinicopathological feature distribution and overall survival (OS) in ACC, the molecular mechanisms, and the value of NAGs in therapy prediction. A nomogram risk model was established to quantify risk stratification for ACC patients. Finally, the results were confirmed in the GEO-combined cohort. Result. Patients in the TCGA-ACC cohort were divided into high and low NAGs groups. The high NAGs group had more fatal cases and advanced stage patients than the low NAGs group ( $P<0.001$ , hazard ratio $\left(\text{HR}\right)=13.97$ , 95% confidence interval (95% CI): 4.168–46.844; survival rate: low NAGs, 7.69% vs. high NAGs, 61.53%). NAGs were validated to be negatively correlated with OS ( $R=-0.48$ , $P<0.001$ ) and act as an independent factor in ACC with high discriminative efficacy ( $P<0.001$ , $\text{HR}=11.76$ , 95% CI: 2.86–48.42). In addition, a high predictive efficacy nomogram risk model was established combining NAGs with tumor stage. Higher mutation rates were observed in the high NAGs group, and the mutation of TP53 may lead to a high T cell infiltration level among the NAGs groups. Patients belonged to the high NAGs are more sensitive to the chemotherapy of cisplatin, gemcitabine, paclitaxel, and etoposide (all $P<0.05$ ). Ultimately, the same statistical algorithms were conducted in the GEO-combined cohort, and the crucial role of NAGs prediction value was further validated. Conclusion. We constructed a necroptosis-associated gene signature, revealed the prognostic value between ACC and it, systematically explored the molecular alterations among patients with different NAGs, and manifested the value of drug sensitivity prediction in ACC.

[Diagnostic value of ct in examination of patients with adrenal cancer]

BACKGROUND

In most cases adrenal tumours are detected by accident while performing medical imaging tests for other diseases. These findings are treated as adrenal incidentaloma. Prevalence of incidentalomas detected on CT scans is up to 4%. According to different authors, 4-12% of all adrenal tumours are adrenocortical carcinomas. As for today, the most significant medical imaging technique is CT scan with bolus IV injection of contrast agent and assessment of tumour's density. The analysis of the results of CT imaging in 67 patients with ACC was carried out according to a single protocol. The main signs characteristic of this disease are described. It is very important to evaluate typical signs of ACC on CT scans for risk assessment of ACC before surgical treatment. If malignant tumour is suspected during preoperative examination, it is extremely important to choose the right surgical treatment strategy.

AIM

To evaluate the significance of CT as the main method of preoperative diagnosis in patients with malignant tumors of the adrenal cortex. Studying CT semiotics of adrenocortical cancer in a large group of patients using a single standard imaging protocol. Find the main radiological symptoms characteristic of adrenocortical cancerMATERIALS AND METHODS: Here are the results of retrospective study of CT scans performed on 67 patients with adrenocortical carcinoma who received treatment in the Department of Endocrine Surgery of Saint-Petersburg State University N.I. Pirogov Clinic of High Medical Technologies during 2012-2020. The diagnostic significance of CT in patients with ACC was assessed.

RESULTS

The most common features of ACC: tumour heterogeneity (84.3%), tumour's size 3-9 cm (75%), signs of invasion into surrounding structures (10%), pre-contrast density above +30 HU (75%), absolute contrast washout less than 60% (68.8%), relative contrast washout less than 40% (64.6%)CONCLUSION: CT scan with IV contrast was not able to show any definitive pathognomonic signs of ACC. Nevertheless, CT scan should be performed in all patients with suspected (or confirmed using other medical imaging technique) adrenal tumour according to standard protocol. Bolus injection of contrast agent should be performed in all patients with tumour's pre-contrast density above +5 HU.

Imaging findings of spontaneous intraabdominal hemorrhage: neoplastic and non-neoplastic causes

Contrary to traumatic and iatrogenic intraabdominal hemorrhages, spontaneous intraabdominal hemorrhage is a challenging clinical situation. A variety of neoplastic and non-neoplastic conditions may cause spontaneous intraabdominal bleeding. Imaging findings vary depending on the source of bleeding and the underlying cause. In this article, we aim to increase the awareness of imagers to the most common causes of spontaneous intraabdominal hemorrhage by using representative cases.

Imaging features of atypical adrenocortical adenomas: a radiological-pathological correlation

OBJECTIVE

Adrenal adenomas are frequently picked up incidentally on cross-sectional imaging and are known to have a classic imaging appearance on CT and MRI. However, not all adrenal adenomas have this typical radiologic appearance. Our aim is to present the radiological features of atypical adrenocortical adenomas with pathological correlation.

METHODS

All the imaging from the pathologically proven adrenal adenoma cases in our hospital (Tallaght University Hospital, Dublin, Ireland) database (from 2004 to 2019) was reviewed. 8 out of 48 cases (16%) had an atypical radiological appearance and were selected for presentation.

RESULTS

Eight cases demonstrated atypical radiological features including heterogeneous density, incomplete washout on post-contrast imaging, the presence of macroscopic fat and calcification. Lipomatous metaplasia was present in two of the cases pathologically.

CONCLUSION

Adrenocortical adenomas are the most common adrenal mass encountered on CT, however, may not always have classic imaging features. Radiologists should be familiar with both the typical and atypical imaging manifestations of these benign adrenal lesions.

ADVANCES IN KNOWLEDGE

This paper comprehensively describes the atypical features of adrenocortical adenomas with case examples and radiologic-pathologic correlation. Guidelines and an approach to the work-up of adrenal lesions with atypical appearances are also provided.

Risk prediction model establishment with tri-phasic CT image features for differential diagnosis of adrenal pheochromocytomas and lipid-poor adenomas: Grouping method

OBJECTIVES

The purpose of this study was to establish a risk prediction model for differential diagnosis of pheochromocytomas (PCCs) from lipid-poor adenomas (LPAs) using a grouping method based on tri-phasic CT image features.

METHODS

In this retrospective study, we enrolled patients that were assigned to a training set (136 PCCs and 183 LPAs) from two medical centers, along with an external independent validation set (30 PCCs and 54 LPAs) from another center. According to the attenuation values in unenhanced CT (CTu), the lesions were divided into three groups: group 1, 10 HU < CTu ≤ 25 HU; group 2, 25 HU < CTu ≤ 40 HU; and group 3, CTu > 40 HU. Quantitative and qualitative CT imaging features were calculated and evaluated. Univariate, ROC, and binary logistic regression analyses were applied to compare these features.

RESULTS

Cystic degeneration, CTu, and the peak value of enhancement in the arterial and venous phase (DEpeak) were independent risk factors for differential diagnosis of adrenal PCCs from LPAs. In all subjects (groups 1, 2, and 3), the model formula for the differentiation of PCCs was as follows: Y = -7.709 + 3.617*(cystic degeneration) + 0.175*(CTu ≥ 35.55 HU) + 0.068*(DEpeak ≥ 51.35 HU). ROC curves were drawn with an AUC of 0.95 (95% CI: 0.927-0.973) in the training set and 0.91 (95% CI: 0.860-0.929) in the external validation set.

CONCLUSION

A reliable and practical prediction model for differential diagnosis of adrenal PCCs and LPAs was established using a grouping method.

The challenge to differentiate between sarcoma or adrenal carcinoma—an observational study

Background

Adrenal sarcomas are rare malignant tumors with structural and clinical similarities to sarcomatoid adrenocortical carcinoma. Preoperative diagnosis of tumors of the adrenal gland can be challenging and often misleading thus detaining patients from appropriate oncological strategies.

Objective

This analysis of a case series evaluated the predictive capability of the primary clinical diagnosis in case of malignancies of the adrenal gland.

Methods

Thirty two patients were treated from 2009 to 2015 at our clinic and analyzed retrospectively. All patients had computed tomography and/or magnet resonance imaging and a primary histopathological examination at our institution after surgery. Ten questionable cases were surveyed by a reference pathologist.

Results

Twelve out of 32 diagnoses had to be revised (37.5%). Only 15 out of 24 tumors primarily classified as adrenocortical carcinoma were finally described as primary adrenal cancer. We found two leiomyosarcomas, one liposarcoma, one sarcomatoid adrenocortical carcinoma, and one epitheloid angiosarcoma among 12 misleading diagnoses. Other tumors turned out to be metastases of lung, hepatocellular, and neuroendocrine tumors. Larger tumors were significantly more often correctly diagnosed compared to smaller tumors. Four patients of the group of revised diagnoses died whereas all patients with confirmed diagnoses survived during the follow-up.

Conclusion

Preoperative assessment of tumors of the adrenal gland is still challenging. In case of wrong primary diagnosis, the prognosis could be impaired due to inadequate surgical procedures or insufficient preoperative oncological treatment.

Are the washout values currently accepted for lesion characterization in dedicated adrenal CT adequate for diagnosis?

PURPOSE

We aimed to investigate the accuracy of density characteristics and washout values of lesions detected on computed tomography (CT) at the cutoff values obtained from the literature by taking the pathological results of adrenalectomy specimens as reference and to determine the cutoff values of parameters evaluated on CT for the differentiation of adenoma and nonadenoma lesions in the study group.

METHODS

Hospital records and standard CT imaging data (noncontrast early phase [65 s] and late phase [15 min] ) of 84 patients with 87 lesions who underwent adrenalectomy between January 2012 and December 2018 were retrospectively reevaluated by two radiologists in consensus. The patients were categorized as having adenoma and nonadenoma lesions according to the pathology results. The sensitivity, specificity and diagnostic accuracy of CT parameters (density values and washout percentages) were evaluated. Differences in the CT parameters (size, noncontrast and early-late enhancement density and absolute and relative washout values) were investigated. The optimal cutoff values of CT parameters were determined by ROC analysis.

RESULTS

Noncontrast CT had a specificity of 87.75% and 95.9%, sensitivity of 60% and 48.6%, diagnostic accuracy of 77.7% and 89.47% for adenomas, at the cutoff values of ≤10 HU and ≤0 HU, respectively. For absolute washout value ≥ 60%, the sensitivity, specificity and accuracy were 64.7%, 52.38% and 56.75%, respectively; while these rates were 76.47%, 56.52% and 62.16%, respectively, for relative washout value ≥40%. Adenomas and nonadenomas showed significant difference in terms of size (p < 0.0001), unenhanced attenuation (p < 0.0001), relative washout (p = 0.020) and delay enhancement (p < 0.001). But there were no differences in terms of absolute washout (p = 0.230) and early enhancement (p = 0.264). The cutoff values for the differentiation of adenomas and nonadenomas were as follows: size ≤44 mm, noncontrast density <20 HU, early-phase density ≥45 HU, delayed-phase density ≤44 HU, absolute washout 74.83% and relative washout 57.76%.

CONCLUSION

The current washout criteria used in the differentiation of adenoma and nonadenoma lesions in dynamic CT imaging can give false negative and positive results. According to the existing criteria, the most reliable parameter in adenoma-nonadenoma differentiation is ≤ 0 HU noncontrast CT density value.

Management of Incidentalomas

Incidental findings are common in the evaluation of surgical patients. Understanding the appropriate assessment and management of these frequent occurrences is important for the provision of comprehensive quality care. This review details the epidemiology, considerations, and recommendations for management of common incidental manifestations in surgical patients, including Meckel diverticulum, adrenal incidentaloma, thyroid nodule, solitary pulmonary nodule, small bowel intussusception, gallstones, and incidental appendectomy.

Adrenal incidentaloma. Part 2. Modern concepts of computed tomography semiotics of adrenal gland incidentalomas: algorithm of differential diagnosis

While accidentally detecting an adrenal gland lesion (incidentaloma) during a routine computed tomography (CT) scan, the radiologist should correctly interpret revealed changes. The most common lesion is adenoma with high lipid content, but a lipid poor adenoma, pheochromocytoma, adrenocortical cancer, metastasis and other less common adrenal diseases are also worth of attention and require detailed knowledge of their CT semiotics. The article presents criteria of differential diagnosis of the adrenal incidentalomas on the basis of which an algorithm of differential diagnosis was proposed for the most common adrenal lesions.

An optimized two-stage cascaded deep neural network for adrenal segmentation on CT images

Segmentation of adrenal glands from CT images is a crucial step in the AI-assisted diagnosis of adrenal gland-related disease. However, highly intrasubject variability in shape and adhesive boundaries with surrounding tissues make accurate segmentation of the adrenal gland a challenging task. In the current study, we proposed a novel two-stage deep neural network for adrenal gland segmentation in an end-to-end fashion. In the first stage, a localization network that aims to determine the candidate volume of the target organ was used in the preprocessing step to reduce class imbalance and computational burden. Then, in the second stage, a Small-organNet model trained with a novel boundary attention focal loss was designed to refine the boundary of the organ within the screened volume. The experimental results show that our proposed cascaded framework outperforms the state-of-the-art deep learning method in segmenting the adrenal gland with respect to accuracy; it requires fewer trainable parameters and imposes a smaller demand on computational resources.

Results of Adrenalectomy for Isolated, Metachronous Metastasis of Breast Cancer: A Retrospective Cohort Study

Background and Aim: Metachronous, isolated adrenal metastases from breast cancer are extremely rare. The aim of this study was to evaluate the results of adrenalectomy as a treatment of this uncommon condition.

Methods: Twelve female patients (median age: 68 years) underwent 13 adrenalectomies for isolated, metachronous metastases of breast cancer. Ten resections were performed thorugh open surgery and two were preformed through a laparoscopic approach. As main study endpoints, postoperative mortality, postoperative morbidity and disease-free survival were considered. Median length of follow-up was 40 months.

Results: Postoperative mortality was absent. Postoperative morbidity was 17%: one patient presented a postoperative pneumothorax requiring drainage and one patient required re-hospitalization 8 days after contralateral adrenalectomy for electrolyte imbalance. Two patients died of recurrent metastatic disease, 28 and 33 months respectively after adrenalectomy. One patient remained alive with hepatic metastases at 32 months from resection of adrenal recurrence. All in all, disease-free survival at 48 months was 75%.

Conclusions: Adrenalectomy for metachronous, isolated metastases of breast cancer can be performed with no postoperative mortality and minimal postoperative morbidity, enabling good long-term disease-free survival.

[Adrenal imaging: anatomy and pathology (literature review)]

This literature review focuses on the normal adrenal gland anatomy and typical imaging features necessary to evaluate benign and malignant lesions. In particular, adenoma, pheochromocytoma, metastases and adrenocortical carcinoma were discussed as some of the most common lesions. For this purpose, a review of relevant local and international literature sources up to January 2021 was conducted.In many cases, adrenal incidentalomas have distinctive features allowing characterization using noninvasive methods. It is possible to suspect a malignant nature and promptly refer the patient for the necessary invasive examinations in some cases. -Computed tomography, especially with intravenous contrast enhancement, is the primary imaging modality because it enables differential diagnosis. Magnetic resonance tomography remains a sensitive method in lesion detection and follow-up but is not very specific for determining the malignant potential. Positron emission computed tomography also remains an additional method and is used mainly for differential diagnosis of malignant tumors, detecting metastases and recurrences after surgical treatment. Ultrasound has a limited role but is nevertheless of great importance in the pediatric population, especially newborns. Promising techniques such as radiomics and dual-energy CT can expand imaging capabilities and improve diagnostic accuracy.Because adrenal lesions are often incidentally detected by imaging performed for other reasons, it is vital to interpret such findings correctly. This review should give the reader a broad overview of how different imaging modalities can evaluate adrenal pathology and guide radiologists and clinicians.

Distinguishing pheochromocytoma from adrenal adenoma by using modified computed tomography criteria

PURPOSE

To investigate the performance of modified criteria to distinguish pheochromocytoma from adrenal adenoma by using adrenal protocol computed tomography (CT).

METHODS

We retrospectively included consecutive 199 patients who underwent adrenal CT and surgically proven pheochromocytoma (n = 66) or adenoma (n = 133). Two independent radiologists analyzed two CT criteria for pheochromocytoma. Conventional criteria were as follows: (a) lesion attenuation on unenhanced CT > 10 Hounsfield unit (HU); (b) absolute percentage washout < 60%; and (c) relative percentage washout < 40%. Modified criteria were as follows: (a) conventional criteria or (b) one of the following findings: (i) lesion attenuation on unenhanced CT ≥ 40 HU, (ii) 1-min enhanced CT ≥ 160 HU, (iii) 15-min enhanced CT ≥ 70 HU, , or (iv) intralesional cystic degeneration seen on both 1-min and 15-min enhanced CT. We analyzed area under the curve (AUC) and inter-reader agreement.

RESULTS

Proportion of pheochromocytoma was 33.2% (66/199). AUC of modified criteria was consistently higher than that of conventional criteria for distinguishing pheochromocytoma from adenoma (reader 1, 0.864 versus 0.746 for raw data set and 0.865 versus 0.746 for internal validation set; reader 2, 0.872 versus 0.758 for raw data set and 0.872 versus 0.757 for internal validation set) (p < 0.05 for all comparisons). Inter-reader agreement was excellent in interpreting any criteria (weighted kappa > 0.800).

CONCLUSION

Our modified criteria seem to improve diagnostic performance of adrenal CT in distinguishing pheochromocytoma from adrenal adenoma.

Hyperattenuating adrenal lesions in lung cancer: biphasic CT with unenhanced and 1-min enhanced images reliably predicts benign lesions

OBJECTIVES

To investigate usefulness of biphasic computed tomography (CT) in characterizing hyperattenuating adrenal lesions in lung cancer.

METHODS

This retrospective study included 239 patients with lung cancer who underwent adrenal CT for hyperattenuating (> 10 Hounsfield unit) adrenal lesions. Adrenal CT comprised unenhanced and 1-min and 15-min enhanced images. We dichotomized adrenal lesions depending on benign or metastatic lesions. Reference standard for benignity was histologic confirmation or ≥ 6-month stability on follow-up CT. Two independent readers analyzed absolute (APW) or relative percentage wash-out (RPW) using triphasic CT, and enhancement ratio (ER) or percentage wash-in (PWI) using biphasic CT (i.e., unenhanced and 1-min enhanced CT). Criteria for benignity were as follows: criteria 1, (a) APW ≥ 60% or (b) RPW ≥ 40%, and criteria 2, (a) ER > 3 and (b) PWI > 200%. We analyzed area under the curve (AUC) and accuracy for benignity, and inter-reader agreement.

RESULTS

Proportion of benign adrenal lesion was 71.1% (170/239). For criteria 1 and 2, AUCs were 0.872 (95% confidence interval [CI], 0.822-0.911) and 0.886 (95% CI, 0.838-0.923), respectively, for reader 1 (p = 0.566) and 0.816 (95% CI, 0.761-0.863) and 0.814 (95% CI, 0.759-0.862), respectively, for reader 2 (p = 0.955), and accuracies were 87.9% (210/239) and 86.2% (206/239), respectively, for reader 1 (p = 0.479) and 81.2% (194/239) and 80.3% (192/239), respectively, for reader 2 (p = 0.763). Weighted kappa was 0.725 (95% CI, 0.634-0.816) for criteria 1 and 0.736 (95% CI, 0.649-0.824) for criteria 2.

CONCLUSION

Biphasic CT can reliably characterize hyperattenuating adrenal lesions in patients with lung cancer.

KEY POINTS

• Criteria from biphasic computed tomography (CT) for diagnosing benign adrenal lesions were enhancement ratio of > 3 and percentage wash-in of > 200%. • In the analysis by two independent readers, area under the curve between criteria 1 and 2 was not significantly different (0.872 and 0.886 for reader 1; 0.816 and 0.814, for reader 2; p > 0.05 for each comparison). • Wash-in characteristics from biphasic CT are helpful to predict benign adrenal lesions in lung cancer.

[Adrenal incidentaloma. Part 1. Computed tomography of adrenal incidentaloma: the possibilities and difficulties of differential diagnosis]

The adrenal incidentaloma is a lesion of a different etiology and found incidentally in patients who underwent a diagnostic study not about the disease of this organ. Lesions can be both hormonally inactive and hormonally active, can arise from different zones of the adrenal gland or have non-specific organ affiliation, can be benign or malignant. Computed tomography characterization of these lesions, especially the differential diagnosis of benign and malignant, is extremely important for the correct diagnosis in order to provide adequate management of the patient. The article presents the key computed tomography criteria that allow radiologist to characterize the lesion most accurately and consider appropriate diagnosis.

11C-metomidate PET in the diagnosis of adrenal masses and primary aldosteronism: a review of the literature

BACKGROUND

Adrenal masses are commonly encountered in clinical practice, many of whom are incidental. Identifying malignancy, and excess hormone production is essential for appropriate management. Biochemical workup and imaging tests (dedicated adrenal CT and/or MRI) are used to determine the likelihood of excessive hormone function and malignancy, respectively. However, imaging cannot provide information about function and biochemical workup cannot localize the source. Furthermore, in primary aldosteronism, adrenal vein sampling, the gold standard for lateralization, has important limitations such as the technical expertise required, the elevated costs, and potential complications. Over the last decades, there has been a renewed interest in alternative noninvasive imaging techniques that provide information about adrenal function without the need for invasive procedures. In this review, we will evaluate the evidence and the potential role of ¹¹C-metomidate as a promising positron emission tomography (PET) tracer in clinical practice.

METHODS

A review of the English literature for articles describing the use of the tracer ¹¹C-metomidate in adrenal disorders.

RESULTS

A total of 12 studies were included in the systematic review, which altogether addressed the use of ¹¹C-metomidate in adrenal masses and the application of this tracer in primary aldosteronism.

CONCLUSIONS

¹¹C-metomidate, a selective inhibitor of 11-β-hydroxylase, demonstrated a high specificity for adrenocortical tissue. In addition, ¹¹C-metomidate is correlated with this enzyme activity making it a potentially useful PET tracer for the identification primary aldosteronism, in addition to detection of adrenocortical masses.

Imaging of Adrenal-Related Endocrine Disorders

Endocrine disorders associated with adrenal pathologies can be caused by insufficient adrenal gland function or excess hormone secretion. Excess hormone secretion may result from adrenal hyperplasia or hormone-secreting (ie, functioning) adrenal masses. Based on the hormone type, functioning adrenal masses can be classified as cortisol-producing tumors, aldosterone producing tumors, and androgen-producing tumors, which originate in the adrenal cortex, as well as catecholamine-producing pheochromocytomas, which originate in the medulla. Nonfunctioning lesions can cause adrenal gland enlargement without causing hormonal imbalance. Evaluation of adrenal-related endocrine disorders requires clinical and biochemical workup associated with imaging evaluation to reach a diagnosis and guide management.

The case series of functional adrenal tumors: Experience of two tertiary hospitals in Yaoundé, Cameroon

•

This is a case series of functional adrenal tumors and treatment outcomes.

•

A diversity of cases is presented with clinical, medical imaging, macroscopic and microscopic features included.

•

Successful management of two cases of adrenal insufficiency following classic adrenalectomy in a low resource community is reported.

Introduction

Adrenal tumors are often found incidentally during abdominal imaging. Functioning adrenal tumors are less frequent than these incidentalomas discovered unexpectedly. We report treatment outcomes (major complications) of 7 cases of symptomatic adrenal masses from 2009 to 2019.

Presentation of the cases

Seven cases of functioning adrenal tumors: four adenomas presenting with Cushing’s syndrome, two adrenal carcinomas, and one pheochromocytoma are described. The preoperative diagnoses were made through clinical manifestations, an increase in urinary free cortisol with normal ACTH, elevated metanephrine and enlarged masses on CT. The diagnoses were established on histopathology of adrenalectomy specimens. Adrenal insufficiency in two patients following surgery was corrected with corticoid replacement therapy. One patient died of hypovolemia the day of surgery and another from anaphylactic shock (allergy) late in the post-operative period.

Discussion

Pre, intra and post-operative complications from vascular instability often complicate surgery in functioning adrenal tumors. Adrenal adenomas manifest as Cushing’s syndrome in 10–15 % of patients. They are the most common adrenal tumor although the diagnosis is most often coincidental to abdominal imaging. The incidence of adrenal adenoma increases with age, up to 7 % in the seventh decade. Laparoscopic adrenalectomy, which was not available in our hospitals then, is standard treatment for most tumors. It is alleged to have better outcomes in trained and tested hands.

Conclusion

Surgery of functioning adrenal tumors demands close collaboration of multiple clinical disciplines to manage vascular instability and adrenal insufficiency, especially in resource strapped communities.

Characteristics of adrenocortical carcinoma in South Korea: a registry-based nationwide survey

PURPOSE

To evaluate the clinical characteristics and prognostic factors in patients with adrenocortical carcinoma (ACC) in South Korea.

METHODS

A nationwide, registry-based survey was conducted to identify pathologically proven ACC at 25 tertiary care centers in South Korea between 2000 and 2014. Cox proportional hazard model and log-rank test were adopted for survival analysis.

RESULTS

Two hundred four patients with ACC were identified, with a median follow-up duration of 20 months (IQR 5-52 months). The median age at diagnosis was 51.5 years (IQR 40-65.8 years), and ACC was prevalent in women (n = 110, 53.9%). Abdominal pain was the most common clinical symptom (n = 70, 40.2%), and ENSAT stage 2 was most common (n = 62, 30.4%) at the time of diagnosis. One hundred sixty-nine patients underwent operation, while 17 were treated with other modalities. The remission rate was 48%, and median recurrence-free survival time was 46 months. Estimated 5-year recurrence-free rate was 44.7%. There were more women, large tumor, atypical mitosis, venous invasion, and higher mitotic count in cancer recurrence group. Estimated 5-year overall survival and disease-specific survival rates were 64.5 and 70.6%, respectively. Higher ENSAT stage and advanced pathologic characteristics were risk factors for all-cause mortality of ACC. Large tumor size and cortisol-secreting tumor were additional risk factors for ACC-specific death.

CONCLUSIONS

We report the first epidemiologic study regarding ACC in an Asian population. ENSAT stage 4; lymph node involvement; non-operative group; and invasion of vein, sinusoid, or capsule were associated with an increased risk for all-cause mortality.

Venous Tumor Thrombosis and Pulmonary Metastases in a Case of Adrenal Neuroblastoma—Occurrence of Two Rare Manifestations in a Single Patient: Case Report and Review of Literature

Unlike other pediatric extra cranial solid neoplasms, neuroblastomas have very low incidence of pulmonary metastases. Neuroblastomas also tend to encase rather than infiltrate the major vessels with very low incidence of tumor thrombus. Even in cases with inferior vena cava tumor thrombosis, pulmonary metastases are a rare occurrence. These patients usually show widespread disseminated disease at presentation. We present a rare case of adrenal neuroblastoma with tumor thrombus and bilateral pulmonary metastases at presentation. This presentation can be confused with adrenocortical carcinoma and differentiating between the two is essential for further management.

Adrenal cortical adenoma: current update, imaging features, atypical findings, and mimics

Adrenal adenoma is the most common adrenal lesion. Due to its wide prevalence, adrenal adenomas may demonstrate various imaging features. Thus, it is important to identify typical and atypical imaging features of adrenal adenomas and to be able to differentiate atypical adrenal adenomas from potentially malignant lesions. In this article, we will discuss the diagnostic approach, typical and atypical imaging features of adrenal adenomas, as well as other lesions that mimic adrenal adenomas.

Adrenal cortical carcinoma: pathology, genomics, prognosis, imaging features, and mimics with impact on management

Adrenocortical carcinoma (ACC) is a rare tumor with a poor prognosis. Most tumors are either metastatic or locally invasive at the time of diagnosis. Differentiation between ACC and other adrenal masses depends on clinical, biochemical, and imaging factors. This review will discuss the genetics, pathological, and imaging feature of ACC.

Imaging features of adrenal gland masses in the pediatric population

The spectrum of adrenal masses in the pediatric population markedly differs from that in the adult population. Imaging plays a crucial role in detecting adrenal masses, differentiating malignant from benign lesions, recognizing extra-adrenal lesions in the suprarenal fossa, and directing further management. Ultrasound is the primary imaging modality of choice for the evaluation of adrenal masses in the neonatal period, whereas MRI or CT is used as a problem-solving tool. In older children, computed tomography or magnetic resonance imaging is often required after initial sonographic evaluation for further characterization of a lesion. Herein, we discuss the salient imaging features along with pathophysiology and clinical features of pediatric adrenal masses.

Tumor in the veins: an abdominal perspective with an emphasis on CT and MR imaging

Endovenous tumor thrombus in abdomen should be accurately diagnosed as it is a significant finding that may change medical and surgical treatment approaches. As some underlying reasons for endovenous tumor thrombi are relatively rare and imaging findings may be quite subtle, they can be easily overlooked which may have important clinical consequences. In this paper, we described the various imaging aspects of endovenous tumor thrombi originating from various tumor types in different venous structures of the abdomen.

Calcified Adrenal Lesions: Pattern Recognition Approach on Computed Tomography With Pathologic Correlation

Incidental adrenal lesions are found in 2% to 10% of the population. The presence and pattern of calcifications, in conjunction with other clinical and imaging features, such as soft tissue attenuation, enhancement, and laterality, can aid in narrowing a differential diagnosis, thereby preventing unnecessary biopsies and avoiding delays in management. Calcified adrenal lesions can be categorized under the clinical and laboratory headings of normal adrenal function, hyperfunctioning adrenal tissue, and adrenal insufficiency. In this review, we provide an algorithmic approach to assessing calcified adrenal nodules with correlative radiologic findings.

Adrenal angiosarcoma with metastasis: Imaging and histopathology of a rare adrenal cancer

Adrenal angiosarcoma is an extremely rare malignancy with few reported cases in the literature. Patients may be asymptomatic or have nonspecific complaints at presentation. There are no pathognomonic imaging findings, while histopathology can be confounding due to overlap with other disease processes. We present a case of a 38-year-old woman with a long history of cocaine abuse who had metastatic adrenal angiosarcoma at the time of presentation. The adrenal tumor was an incidental finding on imaging. CT demonstrated a heterogeneous mass in the right adrenal gland with central calcification, and MRI identified central necrosis in the mass. Histopathology demonstrated sheets of epithelioid cells, dilated anastomotic vascular spaces, and abundant necrosis, and immunohistochemistry was positive for various vascular markers. The findings were consistent with adrenal angiosarcoma. The patient underwent adrenalectomy and is now receiving adjuvant chemotherapy. Due to the aggressive nature of adrenal angiosarcoma, timely diagnosis and treatment is critical. This case adds to the sparse literature surrounding this disease by highlighting crucial imaging and histopathologic findings that will aid in more efficient diagnosis. Although rare, the disease should be considered in the context of suspicious adrenal lesions. In the future, structured review of all reported cases of adrenal angiosarcoma can help inform diagnosis and therapy for this rare disease.

Adrenal collision tumour comprised of adrenocortical carcinoma and myelolipoma in a patient with congenital adrenal hyperplasia

Adrenal myelolipoma is a benign tumour characterized by the presence of macroscopic fat. Further workup is not necessary if a diagnosis of adrenal myelolipoma is obtained via imaging. We report the first case of adrenal collision tumour comprised of adrenocortical carcinoma and myelolipoma in a patient with bilateral myelolipomas and congenital adrenal hyperplasia. Computed tomography showed a large right adrenal mass consisting of two different components: soft tissue with peripheral heterogeneous enhancement and macroscopic fat. Imaging findings reflected features of both adrenocortical carcinoma and myelolipoma. Although this entity is rare, collision tumour containing an adrenocortical carcinoma component should be suspected if portions of an adrenal mass partially consist of peripheral heterogeneous enhancement.

Bilateral Adrenocortical Adenomas along with Virilization and Cushing's Syndrome

We herein present the case of a 27-year-old woman with clinical and biochemical features of virilism. Imaging studies revealed the presence of a bilateral adrenal tumor. Although the secretion of androgens was remarkable, the autonomous production of cortisol was also evident because of a loss of circadian rhythm and the absence of cortisol suppression by dexamethasone. The surgical excision of both adrenal tumors was performed, and the histological examination showed no malignancy. We also report the successful pregnancy and delivery of the patient who showed evolving adrenocortical insufficiency along with virilization and Cushing's syndrome and who continued to receive glucocorticoid replacement therapy during pregnancy.

Imaging features of adrenal masses

The widespread use of imaging examinations has increased the detection of incidental adrenal lesions, which are mostly benign and non-functioning adenomas. The differentiation of a benign from a malignant adrenal mass can be crucial especially in oncology patients since it would greatly affect treatment and prognosis. In this setting, imaging plays a key role in the detection and characterization of adrenal lesions, with several imaging tools which can be employed by radiologists. A thorough knowledge of the imaging features of adrenal masses is essential to better characterize these lesions, avoiding a misinterpretation of imaging findings, which frequently overlap between benign and malignant conditions, thus helping clinicians and surgeons in the management of patients. The purpose of this paper is to provide an overview of the main imaging features of adrenal masses and tumor-like conditions recalling the strengths and weaknesses of imaging modalities commonly used in adrenal imaging.

What the radiologist needs to know: the role of preoperative computed tomography in selection of operative approach for adrenalectomy and review of operative techniques

Adrenalectomy is the standard of care for management of many adrenal tumor types and, in the United States alone, approximately 6000 adrenal surgeries are performed annually. Two general approaches to adrenalectomy have been described; (1) the open approach, in which a diseased adrenal is removed through a large (10-20 cm) abdominal wall incision, and (2) the minimally invasive approach, in which laparoscopy is used to excise the gland through incisions generally no longer than 1-2 cm. Given these disparate technique options, clear preoperative characterization of those specific disease features that inform selection of adrenalectomy approach is critically important to the surgeon. Because most of these features are directly assessed via preoperative abdominal imaging, in particular computed tomography (CT) scanning, a clear mutual understanding among surgeons and radiologists of those adrenal tumor features impacting operative approach selection is vital for planning adrenal surgery. In this context, we review the preoperative CT imaging features that specifically inform adrenalectomy approach selection, provide illustrative examples from our institution's imaging and surgical archives, and provide a stepwise guide to both the open and laparoscopic adrenalectomy approaches.