Computed tomography (CT) scan identified necrosis, but is it a reliable single parameter for discerning between malignant and benign adrenocortical tumors?

BACKGROUND: Adrenocortical carcinoma is a rare malignant tumor with a poor prognosis. Discernment of adrenocortical carcinoma in an adrenal mass through imaging studies is paramount for early surgical treatment. Recently, necrosis has been proposed as a single morphological parameter for adrenocortical carcinoma diagnosis. The aim of this study was to analyze the measures of diagnostic efficiency of necrosis and the different computed tomography-scan features related to adrenocortical carcinoma diagnosis. METHODS: We conducted a case-control study of patients surgically treated for an adrenal mass with histopathological report consistent with adrenocortical carcinoma (cases) and adrenocortical adenoma (control patients) between 1987 and 2019. Radiological features on computed tomography scan were collected. Bivariate and multivariate statistical analyses were performed for the different imaging features. The measures of diagnostic efficiency for each feature were calculated. Concordance analysis between image-detected and histopathological-identified necrosis was performed. RESULTS: Eighteen adrenocortical carcinoma and 41 adrenocortical adenomas were included. Differences between adrenocortical carcinoma and adrenocortical adenoma were found regarding heterogeneity (odds ratio 4.53, 95% confidence interval 2.3-8.9; P < .0001), tumor size ≥4 cm (odds ratio 3.5, 95% confidence interval 2.05-6.14; P < .0001), and attenuation index ≥10 Hounsfield units (odds ratio 1.9, 95% confidence interval 1.3-2.6; P = .001). Necrosis was the most important imaging feature significantly associated with adrenocortical carcinoma (odds ratio 35, 95% confidence interval 5.1-241.6; P < .0001), present in all adrenocortical carcinoma cases. After measures of diagnostic efficiency calculation, necrosis had the highest diagnostic accuracy (98%). Cohen's kappa for concordance between image-detected and histopathological-identified necrosis was 90.4% (P < .0001). CONCLUSION: Computed tomography scan-detected necrosis is a reliable radiological feature to discern adrenocortical carcinoma from adrenocortical adenomas.

Para-chloro-2-[18F]fluoroethyl-etomidate: A promising new PET radiotracer for adrenocortical imaging.

Introduction: [11C]Metomidate ([11C]MTO), the methyl ester analogue of etomidate, was developed as a positron emission tomography (PET) radiotracer for adrenocortical tumours and has also been suggested for imaging in primary aldosteronism (PA). A disadvantage of [11C]MTO is the rather high non-specific binding in the liver, which impacts both visualization and quantification of the uptake in the right adrenal gland. Furthermore, the short 20-minute half-life of carbon-11 is a logistic challenge in the clinical setting. Objectives: The aim of this study was to further evaluate the previously published fluorine-18 (T1/2=109.5 min) etomidate analogue, para-chloro-2-[18F]fluoroethyl etomidate; [18F]CETO, as an adrenal PET tracer. Methods: In vitro experiments included autoradiography on human and cynomolgus monkey (non-human primate, NHP) tissues and binding studies on adrenal tissue from NHPs. In vivo studies with [18F]CETO in mice, rats and NHP, using PET and CT/MRI, assessed biodistribution and binding specificity in comparison to [11C]MTO. Results: The binding of [18F]CETO in the normal adrenal cortex, as well as in human adrenocortical adenomas and adrenocortical carcinomas, was shown to be specific, both in vitro (in humans) and in vivo (in rats and NHP) with an in vitro Kd of 0.66 nM. Non-specific uptake of [18F]CETO in NHP liver was found to be low compared to that of [11C]MTO. Conclusions: High specificity of [18F]CETO to the adrenal cortex was demonstrated, with in vivo binding properties qualitatively surpassing those of [11C]MTO. Non-specific binding to the liver was significantly lower than that of [11C]MTO. [18F]CETO is a promising new PET tracer for imaging of adrenocortical disease and should be evaluated further in humans.

Functional imaging of adrenal cortex. / Estudios de imagen funcional de la corteza adrenal.

The rising number of high-resolution imaging scans has increased the adrenal lesions detection, which require a differential diagnosis. Currently, the most commonly used scans are CT and MRI, but these are sometimes not very specific. In these cases, nuclear medicine scans with 131I-norcolesterol, 11C-metomidate and 18F-fludeoxyglucose help to differentiate benign vs. malignant lesions, to lateralize the involvement in hypersecretion disease, as well as to guide the therapeutic strategy in both unilateral and bilateral lesions.

Functional imaging with 11C-metomidate PET for subtype diagnosis in primary aldosteronism.

OBJECTIVE: Endocrine Society guidelines recommend adrenal venous sampling (AVS) in primary aldosteronism (PA) if adrenalectomy is considered. We tested whether functional imaging of adrenal cortex with 11C-metomidate (11C-MTO) could offer a noninvasive alternative to AVS in the subtype classification of PA. DESIGN: We prospectively recruited 58 patients with confirmed PA who were eligible for adrenal surgery. METHODS: Subjects underwent AVS and 11C-MTO-PET without dexamethasone pretreatment in random order. The lateralization of 11C-MTO-PET and adrenal CT were compared with AVS in all subjects and in a prespecified adrenalectomy subgroup in which the diagnosis was confirmed with immunohistochemical staining for CYP11B2. RESULTS: In the whole study population, the concordance of AVS and 11C-MTO-PET was 51% and did not differ from that of AVS and adrenal CT (53%). The concordance of AVS and 11C-MTO-PET was 55% in unilateral and 44% in bilateral PA. In receiver operating characteristics analysis, the maximum standardized uptake value ratio of 1.16 in 11C-MTO-PET had an AUC of 0.507 (P = n.s.) to predict allocation to adrenalectomy or medical therapy with sensitivity of 55% and specificity of 44%. In the prespecified adrenalectomy subgroup, AVS and 11C-MTO-PET were concordant in 10 of 19 subjects with CYP11B2-positive adenoma and in 6 of 10 with CYP11B2-positivity without an adenoma. CONCLUSIONS: The concordance of 11C-MTO-PET with AVS was clinically suboptimal, and did not outperform adrenal CT. In a subgroup with CYP11B2-positive adenoma, 11C-MTO-PET identified 53% of cases. 11C-MTO-PET appeared to be inferior to AVS for subtype classification of PA.

Potassium losing, aldosterone producing adrenocortical carcinoma: a rare presentation.

Adrenocortical carcinomas (ACCs) are rare malignancies with an incidence of one to two per million per year. Aldosterone-producing ACCs (APACs) are extremely rare with an incidence less than 1%. We describe a rare case of APAC, presenting with episodic lower-limb weakness and hypertension. Our patient was found to have serum aldosterone levels of 20.8 ng/dL (2.5-15.2) with persistent hypokalaemia and a 9.7×8.3×7.7 cm right adrenal mass, which was suspicious of malignancy on evaluation. He underwent a complete surgical resection which confirmed the diagnosis of ACC and normalised his aldosterone and potassium levels. He was then subjected to postoperative chemotherapy. Postoperative adjuvant chemotherapy with mitotane has a role in preventing recurrence.

Adrenocortical hyperplasia: a review of clinical presentation and imaging.

Adrenal hyperplasia is non-malignant enlargement of the adrenal glands, which is often bilateral. It can be incidental or related to indolent disease process and may be related to benign or malignant etiologies causing biochemical alterations in the hypothalamic-pituitary-adrenal axis which controls steroidogenesis and in particular cortisol production. Clinical significance of the adrenal hyperplasia is variable ranging from asymptomatic finding to serious manifestations of Cushing syndrome. This is often associated with anatomical changes in the adrenal glands, which typically manifests as diffuse and sometimes nodular enlargement of the adrenal glands radiologically. Approaching adrenal hyperplasia requires careful clinical and biochemical evaluation in correlation with imaging review to differentiate ACTH-dependent and ACTH-independent etiologies. CT is the primary modality of choice for adult adrenal imaging owing to reproducibility, temporal and spatial resolution and broader access, while MRI often serves a complimentary role. Ultrasound and MRI are most commonly used in pediatric cases to evaluate congenital adrenal hyperplasia. This article will discuss the clinical presentation and imaging features of different types and mimics of adrenal cortical hyperplasia.

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.

Urine Steroid Metabolomics as a Novel Tool for Detection of Recurrent Adrenocortical Carcinoma.

CONTEXT: Urine steroid metabolomics, combining mass spectrometry-based steroid profiling and machine learning, has been described as a novel diagnostic tool for detection of adrenocortical carcinoma (ACC). OBJECTIVE, DESIGN, SETTING: This proof-of-concept study evaluated the performance of urine steroid metabolomics as a tool for postoperative recurrence detection after microscopically complete (R0) resection of ACC. PATIENTS AND METHODS: 135 patients from 14 clinical centers provided postoperative urine samples, which were analyzed by gas chromatography-mass spectrometry. We assessed the utility of these urine steroid profiles in detecting ACC recurrence, either when interpreted by expert clinicians or when analyzed by random forest, a machine learning-based classifier. Radiological recurrence detection served as the reference standard. RESULTS: Imaging detected recurrent disease in 42 of 135 patients; 32 had provided pre- and post-recurrence urine samples. 39 patients remained disease-free for ≥3 years. The urine "steroid fingerprint" at recurrence resembled that observed before R0 resection in the majority of cases. Review of longitudinally collected urine steroid profiles by 3 blinded experts detected recurrence by the time of radiological diagnosis in 50% to 72% of cases, improving to 69% to 92%, if a preoperative urine steroid result was available. Recurrence detection by steroid profiling preceded detection by imaging by more than 2 months in 22% to 39% of patients. Specificities varied considerably, ranging from 61% to 97%. The computational classifier detected ACC recurrence with superior accuracy (sensitivity = specificity = 81%). CONCLUSION: Urine steroid metabolomics is a promising tool for postoperative recurrence detection in ACC; availability of a preoperative urine considerably improves the ability to detect ACC recurrence.

Concurrent pituitary and adrenocortical lesions on computed tomography imaging in dogs with spontaneous hypercortisolism.

BACKGROUND: Spontaneous hypercortisolism or Cushing's syndrome in dogs is either pituitary or adrenal dependent, but concurrent pituitary and adrenal hypercortisolism also has been reported. OBJECTIVE: To determine how often concurrent pituitary and adrenal lesions are present in dogs with spontaneous hypercortisolism. ANIMALS: Two hundred one client-owned dogs with spontaneous hypercortisolism. METHODS: Retrospective study. Pre- and post-contrast computed tomography (CT) scans of the pituitary and adrenal glands were performed in dogs with confirmed hypercortisolism. RESULTS: In dogs with dexamethasone-suppressible hypercortisolism (122/201), 78 dogs (64%) had an enlarged pituitary gland (median pituitary height/brain area [P/B], 0.43 × 10-2 mm-1 ; range, 0.32-1.21 × 10-2 mm-1 ). Two of these 78 dogs had concurrent adrenal lesions. In the remaining dogs (44/122; 36%), the pituitary gland was not enlarged. In the dexamethasone-resistant group (79/201), the pituitary gland was enlarged in 47 dogs (59%; median P/B, 0.57 × 10-2 ; range, 0.32-1.50 × 10-2 mm-1 ). Eight of these 47 dogs (17%) had concurrent adrenal lesions. In the remaining 32 dexamethasone-resistant dogs (41%), the pituitary gland was not enlarged. Among them, 27 dogs had adrenal lesions and suppressed ACTH concentrations consistent with adrenal-dependent hypercortisolism and 5 dogs were diagnosed with pituitary-dependent hypercortisolism. CONCLUSIONS AND CLINICAL IMPORTANCE: Concurrent pituitary and adrenal lesions were present in 5% of all dogs with hypercortisolism and in 10% of the dexamethasone-resistant dogs. Diagnostic imaging of both pituitary and adrenal glands should be included in the diagnostic evaluation of every dog with spontaneous hypercortisolism to obtain information needed for estimation of prognosis and choosing the optimal treatment.

Rebound thymic hyperplasia after adrenalectomy in a patient with Cushing syndrome caused by adrenocortical adenoma: A case report.

RATIONALE: The development of rebound thymic hyperplasia (RTH) has been reported in patients who have recovered from stressful conditions such as surgery and steroid therapy. We report a case of RTH following the resolution of hypercortisolism after adrenalectomy for the treatment of adrenocortical adenoma in a patient with Cushing syndrome. PATIENT CONCERNS: A 5-month-old female infant with a history of overeating, hirsutism, and excessive weight gain for the previous 2 months was referred to the hospital. The laboratory results revealed elevated 24-hour urinary free cortisol levels. An overnight dexamethasone suppression test showed no response. Abdominal imaging revealed a right-sided suprarenal mass measuring 4_3cm. Histology showed an adrenocortical adenoma. Thus, she underwent a right adrenalectomy. DIAGNOSES: The patient showed clinical improvement with weight loss and normal cortisol levels over the next 4 months. Six months after the operation, a chest computed tomography showed enlargement of the left thymic lobe, which was previously nonexistent. INTERVENTIONS: A fine needle aspiration biopsy was performed, and histological examination revealed diffuse thymic hyperplasia. OUTCOMES: At the 1-year follow-up, the chest imaging studies showed resolution of the RTH. LESSIONS: An understanding of RTH after adrenalectomy as a treatment for cortisol-producing adrenocortical tumors is important for the prevention of unnecessary surgical intervention and therapy.

BILATERAL ADRENOCORTICAL CARCINOMA: CASE REPORT AND REVIEW OF LITERATURE.

Adrenocortical carcinoma is a very rare and aggressive endocrinological malignancy arising from the adrenal cortex. The estimated incidence is 1 per million people, with an estimated 5-year survival rate of 16-47%. It can be bilateral in roughly 2-10% of cases, but the data is scarce and there is no conclusive evidence whether the contralateral mass is an independent tumor or a metastasis from the other adrenal gland cancer. Radical surgical excision is the only curative treatment. Therefore, careful pre- and intraoperative surgical planning is critically important. Open adrenalectomy has historically been the gold standard approach for surgical treatment of adrenocortical carcinoma. Laparoscopic adrenalectomy has emerged as a minimally invasive alternative, but its oncological safety and effectiveness has long been under debate. Current evidence suggests that in experienced hands laparoscopic adrenalectomy is as safe and effective as its open counterpart in the treatment of localized adrenocortical carcinoma and the adrenal masses ≤10 cm. Urologists have been tempted to apply laparoscopy also to bilateral disease, although the need to reposition the patient and a longer operative time can be limitations. Given the rarity of adrenocortical carcinoma and the lack of quality evidence for the bilateral disease, we used the conventional narrative strategy to review the available literature. We also report a case of nonfunctioning bilateral adrenocortical carcinoma in a 65-year old man, who was operated on with simultaneous bilateral laparoscopic adrenalectomy for suspected localized (stage 2) disease, which proved to be bilateral locally advanced carcinoma (stage 3). Postoperatively, the disease rapidly progressed to the fatal outcome. The case once again highlights the importance of detailed operative planning and the need of imaging studies as close as possible to the date of planned surgery.

Confirmatory Tests for the Diagnosis of Primary Aldosteronism: A Prospective Diagnostic Accuracy Study.

The diagnosis of primary aldosteronism typically requires at least one confirmatory test. The fludrocortisone suppression test is generally accepted as a reliable confirmatory test, but it is cumbersome. Evidence from accuracy studies of the saline infusion test (SIT) and the captopril challenge test (CCT) has provided conflicting results. This prospective study aimed to evaluate the diagnostic accuracy of the SIT and CCT using fludrocortisone suppression test as the reference standard. One hundred thirty-five patients diagnosed with primary aldosteronism and 101 patients diagnosed with essential hypertension who completed the 3 confirmatory tests were included for the diagnostic accuracy analysis. The areas under the receiver-operator characteristics curves of the CCT and SIT were 0.96 (95% confidence interval [CI], 0.92-0.98) and 0.96 (95% CI, 0.92-0.98), respectively, using post-test plasma aldosterone concentration (PAC) for diagnosis. However, the areas under the receiver-operator characteristics curves of the CCT decreased to 0.71 (95% CI, 0.65-0.77) when the PAC suppression percentage was used to diagnose primary aldosteronism. The optimal cutoff of PAC post-CCT was set at 11 ng/dL, resulting in a sensitivity of 0.90 (95% CI, 0.84-0.95) and a specificity of 0.90 (95% CI, 0.83-0.95), which were not significantly different from those of SIT (with PAC post-SIT set at 8 ng/dL, sensitivity: 0.85 [95% CI, 0.78-0.91], P=0.192; specificity: 0.92 [95% CI, 0.85-0.97], P=0.551). In conclusion, both CCT and SIT are accurate alternatives to the more complex fludrocortisone suppression test. Because CCT is safe and much easier to perform, it may serve as a more feasible alternative. When interpreting the results of CCT, PAC post-CCT is highly recommended.

Prediction of Adrenal Adenomas With Hypercortisolism by Using Adrenal Computed Tomography: Emphasis on Contralateral Adrenal Thinning.

PURPOSE: To analyze computed tomography (CT) characteristics of adrenal adenomas with hypercortisolism on adrenal CT compared to adenomas with hyperaldosteronism. MATERIALS AND METHODS: Thirty-two adrenal adenomas, consisting of group A (hypercortisolism, n = 16) and group B (hyperaldosteronism, n = 16), were evaluated with adrenal CT. Thirty-four patients without adrenal nodule on CT and hormonal abnormality (group C) were selected for comparison. In adenomas, lesion size, attenuation value, and absolute and relative washout were compared between groups A and B. The mean adrenal thickness was compared quantitatively and qualitatively between groups. RESULTS: All of adenomas satisfied absolute (≥60%) or relative (≥40%) washout criteria of adrenal CT. The mean adrenal thickness was 1.6 ± 0.3 mm in group A, 2.9 ± 0.5 mm in group B, and 3.0 ± 0.4 mm in group C (group A versus B or C, P < 0.001; group B versus C, P = 0.775). For differentiating group A from B, the area under the curve of quantitative and qualitative analyses for contralateral adrenal thickness was 0.982 and 0.934, respectively. Both sensitivity and specificity with cutoff of 2.0 mm or less in thickness and probably thin or more in visual score were 93.7% and 93.7%, and 87.5% and 93.7%, respectively, for predicting group A. CONCLUSIONS: Contralateral adrenal thinning on CT helps predict adrenal adenomas with hypercortisolism.

Pediatric adrenocortical neoplasms: can imaging reliably discriminate adenomas from carcinomas?

BACKGROUND: There is a paucity of literature describing and comparing the imaging features of adrenocortical adenomas and carcinomas in children and adolescents. OBJECTIVE: To document the CT and MRI features of adrenocortical neoplasms in a pediatric population and to determine whether imaging findings (other than metastatic disease) can distinguish adenomas from carcinomas. MATERIALS AND METHODS: We searched institutional medical records to identify pediatric patients with adrenocortical neoplasms. Pre-treatment CT and MRI examinations were reviewed by two radiologists in consensus, and pertinent imaging findings were documented. We also recorded relevant histopathological, demographic, clinical follow-up and survival data. We used the Student's t-test and Wilcoxon rank sum test to compare parametric and nonparametric continuous data, and the Fisher exact test to compare proportions. We used receiver operating characteristic (ROC) curve analyses to evaluate the diagnostic performances of tumor diameter and volume for discriminating carcinoma from adenoma. A P-value ≤0.05 was considered statistically significant. RESULTS: Among the adrenocortical lesions, 9 were adenomas, 15 were carcinomas, and 1 was of uncertain malignant potential. There were no differences in mean age, gender or sidedness between adenomas and carcinomas. Carcinomas were significantly larger than adenomas based on mean estimated volume (581 ml, range 16-2,101 vs. 54 ml, range 3-197 ml; P-value = 0.003; ROC area under the curve = 0.92) and mean maximum transverse plane diameter (9.9 cm, range 3.0-14.9 vs. 4.4 cm, range 1.9-8.2 cm; P-value = 0.0001; ROC area under the curve = 0.92). Carcinomas also were more heterogeneous than adenomas on post-contrast imaging (13/14 vs. 2/9; odds ratio [OR] = 45.5; P-value = 0.001). Six of 13 carcinomas and 1 of 8 adenomas contained calcification at CT (OR = 6.0; P-value = 0.17). Seven of 15 children with carcinomas exhibited metastatic disease at diagnosis, and three had inferior vena cava invasion. Median survival for carcinomas was 27 months. CONCLUSION: In our experience, pediatric adrenocortical carcinomas are larger, more heterogeneous, and more often calcified than adenomas, although there is overlap in their imaging appearances.

Germline PRKACA amplification leads to Cushing syndrome caused by 3 adrenocortical pathologic phenotypes.

We describe the pathology of 5 patients with germline PRKACA copy number gain and Cushing syndrome: 4 males and 1 female, aged 2 to 43 years, including a mother and son. Imaging showed normal or slightly enlarged adrenal glands in 4 patients and a unilateral mass in the fifth. Biochemically, the patients had corticotropin-independent hypercortisolism. Four underwent bilateral adrenalectomy; unilateral adrenalectomy was performed in the patient with the adrenal mass. Pathologically, 3 patients, including the 1 with the tumor (adenoma), had primary pigmented nodular adrenocortical disease with extranodular cortical atrophy and mild intracapsular and extracapsular extension of cortical cells. The other 2 patients had cortical hyperplasia and prominent capsular and extracapsular micronodular cortical hyperplasia. Immunoperoxidase staining revealed differences for synaptophysin, inhibin-A, and Ki-67 (nuclei) in the atrophic cortices (patients 1, 2, and 3) and hyperplastic cortices (patients 4 and 5) and for Ki-67 (nuclei) and vimentin in the extracortical nodules in the 2 groups of patients. ß-Catenin stained the cell membrane, cytoplasm, and nuclei of the adenoma. The patients were well at follow-up (1-23 years); 24-hour urinary cortisol excretion was elevated in the patient who had unilateral adrenalectomy.

[¹²³I]Iodometomidate imaging in adrenocortical carcinoma.

CONTEXT: Imaging with [¹²³I]iodometomidate ([¹²³I]IMTO) has been shown to diagnose adrenocortical lesions with high sensitivity and specificity. OBJECTIVE: Our objective was to evaluate the clinical utility of [¹²³I]IMTO imaging in adrenocortical carcinoma (ACC). DESIGN: We conducted a prospective monocentric diagnostic study and a prospective case series at a single tertiary referral center. PATIENTS AND INTERVENTIONS: Fifty-eight patients with histologically confirmed ACC, all European Network for the Study of Adrenal Tumors stage IV (with distant metastases), received 185 MBq [¹²³I]IMTO. Sequential planar whole-body scans until 24 hours post injection and single photon emission computed tomography/computed tomography (SPECT/CT) hybrid imaging 4 to 6 hours post injection were performed. MAIN OUTCOME MEASURES: Outcome measures included uptake of [¹²³I]IMTO in ACC lesions, sensitivity and specificity of [¹²³I]IMTO imaging compared with conventional imaging, and number of patients eligible for [¹³¹I]IMTO therapy. RESULTS: Of 430 lesions detected by conventional imaging, 30% showed strong, 8% moderate, and 62% no tracer accumulation. [¹²³I]IMTO detected both primary and metastatic lesions of ACC. However, a substantial percentage of lesions failed to show [¹²³I]IMTO uptake. The overall sensitivity and specificity values were 38% and 100%, respectively. Thirty-four patients (59%) had at least 1 [¹²³I]IMTO-positive lesion. Cortisol and aldosterone secretion by ACC was positively correlated to [¹²³I]IMTO uptake (P = .01); cytotoxic chemotherapy and mitotane treatment presumably did not influence tracer uptake. Twenty-one patients (36.2%) had radiotracer uptake in all lesions ≥ 2 cm and therefore were potential candidates for targeted systemic radiotherapy with [¹³¹I]IMTO. CONCLUSION: About one-third of patients with ACC show specific retention of [¹²³I]IMTO in metastatic lesions. This study provides support for the conduct of a prospective trial to determine whether the first molecular informed therapy using [¹³¹I]IMTO will be of value to patients with metastatic ACC.