Unknown primary cancer presenting as an adrenal mass: frequency and implications for diagnostic evaluation of adrenal incidentalomas

Bilateral primary adrenal diffuse large B cell lymphoma: A rare presentation

Primary lymphoma of the adrenal gland is an uncommon origin of adrenal tumors; it must be explicitly invoked anytime bilateral adrenal affections are revealed. We report a case of bilateral primary adrenal diffuse large B cell lymphoma and perform a review of the literature. Our patient was a 55-year-old man who presented night sweats and a feeling of cardiac palpitations all evolving in a context of deterioration of his general condition. An ultrasound study was requested reporting a bilateral mass corresponding to the adrenal region. A thoraco-abdominopelvic CT scan was requested and revealed bilateral homogenous, polylobed, adrenal masses, discreetly enhanced after injection of contrast product. These masses were associated with multiple retroperitoneal, para-aortic, and celio-mesenteric adenopathies. Anatomopathologic examination of the percutaneous CT-guided biopsy specimen of the adrenal tumor revealed the presence of diffuse large B cell lymphoma grade IIIB according to the Ann Arbor system. Primary adrenal lymphoma PAL on its own is an extremely rare disease entity and less than 100 cases have been reported in the last 40 years. A large proportion of PAL case reports showed that this disease usually has no excretory endocrine function and the symptoms are due to the pressure effect of the mass, whereas adrenal insufficiency usually exists. Our patient presented symptoms of indrenal insufficiency which seems to be the reason for the early diagnosis. Primary bilateral adrenal lymphoma is very rare entity that should be kept in mind whenever bilateral adrenal masses are assessed in the CT scan images.

Imaging Recommendations for Diagnosis, Staging, and Management of Adrenal Tumors

Adrenal glands are affected by a wide variety of tumors apart from infective and inflammatory lesions and their noninvasive characterization on imaging is important for the management of these patients. Incidentalomas form the major bulk of adrenal tumors and differentiation of benign adenomas from other malignant lesions, especially in patients with a known malignancy, guide further management. Imaging is an integral part of management along with clinical and biochemical features. The cornerstone of clinical and biochemical evaluation of adrenal tumors is to determine whether the lesion is functional or nonfunctional. Computed tomography (CT) is considered as the workhorse for imaging evaluation of adrenal lesions. CT densitometry and CT contrast washout characteristics are quite reliable in differentiating adenomas from malignant lesions. CT is also the modality of choice for the evaluation of resectability and staging of primary adrenal tumors. Magnetic resonance imaging (MRI) has superior contrast resolution compared to other morphological imaging modalities and is generally used as a problem-solving tool. MRI chemical shift imaging can also be used to reliably detect adrenal adenomas. Ultrasonography (USG) is used as a screening tool that is usually followed by either CT or MRI to better characterize the tumor and it is not routinely used for assessing the resectability, staging, and characterization of adrenal tumors. Another important role of USG is in image-guided sampling of tumors. Fluorodeoxyglucose positron emission tomography-computed tomography and other nuclear medicine modalities are a valuable addition to morphological imaging modalities. Image-guided interventions also play an important role in obtaining tissue samples where diagnostic imaging is not able to characterize adrenal tumors. In the functioning of adrenal tumors, adrenal venous sampling is widely used to accurately lateralize the secreting tumor.

Incidental, Solitary, and Unilateral Adrenal Metastasis as the Initial Manifestation of Lung Adenocarcinoma

An adrenal incidentaloma is an adrenal mass ≥ 1 cm in size discovered on imaging performed for indications other than suspected adrenal disease. It has variable etiologies, which can be benign or malignant, including primary or metastatic disease. We present a rare case of metastatic lung adenocarcinoma with isolated unilateral adrenal metastases, presenting as an adrenal incidentaloma in an asymptomatic patient with no known history of malignancy. A 76-year-old man with a past medical history of chronic obstructive pulmonary disease (COPD) and heavy tobacco use was admitted for the evaluation and treatment of pneumonia. He was found to have an incidental 4.6 cm unilateral adrenal mass on his CT chest. He underwent a workup for the mass, including further imaging studies that were indeterminate and a hormonal workup that concluded that the mass was nonfunctional. Due to the patient's comorbidities, it was determined that he was not a surgical candidate. A multidisciplinary team recommended a biopsy, which revealed metastatic lung adenocarcinoma. The primary lung cancer was located using positron emission tomography with 2-deoxy-2-(fluorine-18) fluoro-D-glucose combined with computed tomography (F-FDG-PET/CT). The patient was evaluated by an oncology service and started on chemotherapy. In this case report, we discuss the approach for evaluating adrenal incidentalomas as well as the role the biopsy has in this process based on a literature review. In addition, we draw a comparison between our case and similar cases in the literature while highlighting the differences that make this case unique.

Brain and Adrenal Metastasis From Unknown Primary Tumor: A Case Report

The clinical management of brain metastasis (BM) and adrenal metastasis (AM) of cancer of unknown primary (CUP) can be challenging. A 73-year-old man presented to the hospital with sudden-onset hemiplegia. His laboratory data were normal, except for elevated levels of carcinoembryonic antigen (CEA) (33.8 ng/mL). Contrast-enhanced magnetic resonance imaging revealed a 2-cm mass with ring enhancement in the right parietal lobe and extensive vasogenic edema around the tumor. The lesion was diagnosed as BM; however, we could not detect the primary origin by fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT). Stereotactic radiotherapy was then administered, resulting in reduced tumor size and relief of symptoms. Follow-up after one year revealed an elevated CEA level (148.6 ng/mL) and remarkable fluorodeoxyglucose (FDG) uptake in the right adrenal gland, with an area of enhancement of 20 mm, on FDG-positron emission tomography computed tomography, with normal findings in other distant organs. He underwent adrenalectomy, and the adrenal tumor was diagnosed as a poorly differentiated adenocarcinoma likely of lung origin based on the histopathologic and immunohistochemistry findings of cytokeratin (CK) 7 (+), CK 20 (-), thyroid transcription factor-1 (TTF-1) (+), inhibin (-), napsin A (+), prostate-specific antigen (PSA) (-), caudal type homeobox 2 (CDX-2) (-), synaptophysin (-), and p40 (-). Metastatic tumors of unknown primary origin remain latent. Aggressive treatment of these lesions can be beneficial for symptom relief, diagnosis, and prolongation of survival.

Incidental Adrenal Mass in a Patient With Surgically Treated Lung Adenocarcinoma

Adrenal metastases are not uncommon in patients with widespread metastatic lung cancer. Isolated metachronous adrenal metastases in cases of surgically treated lung cancer without long-term evidence of disease are rare and may pose a diagnostic and treatment dilemma. The current literature suggests that in such cases, adrenalectomy provides better median and overall survival rates. This case presents an incidentally discovered isolated adrenal mass in a patient with a past medical history of lung adenocarcinoma that was surgically removed three years before metastasis discovery. The patient successfully underwent adrenalectomy and was disease-free with no apparent complications at her three-month follow-up visit. The case highlights the importance of long-term radiographic surveillance after surgical resection of lung adenocarcinoma for the prompt diagnosis and timely treatment of metachronous metastases.

Carcinoma of unknown primary origin with isolated adrenal metastasis: a report of two cases

The adrenal glands are one of the most common sites of malignant tumor metastasis. However, metastatic adrenal carcinoma of unknown primary origin with localized adrenal gland involvement is an extremely rare condition. Herein, we reported two cases of carcinoma of unknown primary origin with isolated adrenal metastasis. In the first case, back pain was the trigger; while in the second case, the triggers were low fever and weight loss. Metabolic abnormalities such as hypertension and obesity were not detected in either case. Neither patient had relevant previous medical histories, including malignancy. However, both had a long-term history of smoking. Systemic imaging studies revealed only adrenal tumors and surrounding lesions. Primary adrenocortical carcinoma was initially suspected, and chemotherapy including mitotane was considered. However, due to difficulty in complete resection of the tumor, core needle tumor biopsies were performed. Histopathological examination of biopsy specimens led to the diagnosis of carcinoma of unknown primary origin with isolated adrenal metastasis. In both cases, additional laboratory testing showed high levels of serum squamous cell carcinoma-related antigen and serum cytokeratin fragment. Malignant lesions confined to the adrenal glands are rare. As in our cases, it could be occasionally difficult to differentiate non-functioning primary adrenocortical carcinoma from metastatic adrenal carcinoma of unknown primary origin localized to the adrenal gland. If the lesion is unresectable and there are elevated levels of several tumor markers with no apparent hormonal excess, core needle tumor biopsy should be considered to differentiate the primary tumor from the metastatic tumor.

Nonseminomatous Germ-Cell Tumor Presenting as Bilateral Adrenal Masses

Objective

Many tumors can metastasize to the adrenal glands, making the diagnosis of adrenal masses challenging. Awareness that rare primary tumors can metastasize to the adrenals and consideration of biopsy for their diagnosis, sometimes at extra-adrenal sites, is essential to prevent unnecessary adrenalectomies and facilitate the right treatment. We report a rare case of bilateral adrenal masses due to metastasis from a nonseminomatous germ-cell tumor of a retroperitoneal lymph node origin.

Methods

The diagnosis of the adrenal masses from the nonseminomatous germ-cell tumor of a retroperitoneal lymph node origin was based on a retroperitoneal lymph node core biopsy. An initial core biopsy of the adrenal gland revealed necrotic tissue and inflammatory cells without evidence of malignancy. Due to nondiagnostic findings, the core biopsy was repeated, which showed degenerating cells with a high mitotic index and immunohistochemical staining positive for vimentin, suggesting the possibility of a high-grade sarcoma. A retroperitoneal lymph node biopsy was performed. The patient was started on chemotherapy.

Results

A 34-year-old man presented with acute left upper-abdominal pain of 2 weeks and tenderness on the left upper quadrant of the abdomen, and he was found to have bilateral adrenal masses. Laboratory results showed the following: adrenocorticotropic hormone 41 pg/mL (7-69 pg/mL), metanephrine <0.1 nmol/L (0-0.49 nmol/L), normetanephrine 0.99 nmol/L (0-0.89 nmol/L), and morning cortisol 3.1 μg/dL after a 1-mg dexamethasone-suppression test. His dehydroepiandrosterone sulfate level was 62 μg/dL (120-520 μg/dL), and 17OH progesterone level was 36 ng/dL (<138 ng/dL); androstenedione and serum estradiol levels were normal. Laboratory tests for tumor markers revealed the following: testosterone 21 ng/dL (241-827 ng/dL), prostate-specific antigen 0.57 ng/mL (0-4 ng/mL), alpha-fetoprotein 1.9 IU/mL (0.6-6 IU/ml), and beta-human chorionic gonadotropin 134 mIU/mL (0-1 mIU/mL).

Conclusion

We report a rare case of rapidly progressing adrenal masses in a young man, found to have metastasized from nonseminomatous germ-cell tumors. Histopathologic confirmation of the metastatic tumor was done, which prevented unnecessary adrenalectomy. The patient received appropriate chemotherapy.

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.

Comparison of synchronous bilateral transperitoneal and posterior retroperitoneal laparoscopic adrenalectomy: results of a multicenter study

BACKGROUND

Different techniques for laparoscopic adrenalectomy have been proposed with the lateral transperitoneal approach and posterior retroperitoneal approach being the two more frequently minimally invasive surgeries in most of the clinics. There are no sufficient studies in which the results of lateral transperitoneal and posterior retroperitoneal approaches in synchronous bilateral laparoscopic adrenalectomy have been compared. In the current study, we aimed to report our multicenter results of the lateral transperitoneal and posterior retroperitoneal synchronous bilateral laparoscopic adrenalectomy experience in patients who had different bilateral adrenal pathologies and to compare the outcomes of these two different operative procedures.

METHODS

Between 2012 and 2018, a total of 52 patients with a mean age of 43.5 years underwent simultaneous bilateral laparoscopic adrenalectomy at 6 different centers. Twenty-seven and 25 patients underwent bilateral lateral transperitoneal and posterior retroperitoneal laparoscopic adrenalectomy, respectively. Patients' age, gender, body max index, operative indications, mass size, operation time, blood loss, length of hospitalization, intraoperative and postoperative complications and pathology reports were analyzed.

RESULTS

Synchronous bilateral transperitoneal group was younger than synchronous posterior retroperitoneal group (37 years vs. 50.4 years.) (p: 0.001). Posterior retroperitoneal group had significantly decreased operating time and less blood loss than transperitoneal group. No significant difference was found with regard to postoperative hospital stay, perioperative and postoperative complications between two groups. Majority of the histopathological results were adrenal hyperplasia associated with Cushing's disease (61.5%). Less frequent pathological results were adrenal adenoma and pheochromocytoma (15.4% and 13.5%, respectively). During the follow-up period, no recurrence or disease-related mortality was observed in the patients.

CONCLUSION

Our results shows that shorter operative time and less bleeding can be achieved with posterior retroperitoneal approach in synchronous bilateral laparoscopic adrenalectomy. In our series, intraoperative and postoperative complication rates were similar between both surgical approaches.

Minimally Invasive Surgery for Primary and Metastatic Adrenal Malignancy

Since the first description of laparoscopic adrenalectomy (LA) for pheochromocytoma and Cushing syndrome in 1992, the utilization of and indications for a minimally invasive approach to the adrenal gland have vastly expanded. Although minimally invasive adrenalectomy has been established as the preferred approach for patients with benign tumors of the adrenal gland, minimally invasive adrenalectomy for cancer remains controversial. In this article, the authors review the indications for minimally invasive adrenalectomy for adrenal nodules suspicious for, or established to represent, a primary malignancy or a site of metastatic cancer.

Primary adrenal insufficiency due to bilateral infiltrative disease

PURPOSE

Evidence on clinical presentation, evaluation, and management of patients with primary adrenal insufficiency (PAI) due to bilateral adrenal infiltrative disease is scarce. Our objective was to review the clinical presentation, biochemical work-up, imaging findings, and management of patients with PAI due to infiltrative adrenal disease in order to determine the best diagnostic and management approach.

METHODS

Retrospective study of patients with PAI due to bilateral infiltrative adrenal disease referred for adrenal biopsy during 2000-2014 at Mayo Clinic, Rochester, Minnesota. Two additional patients evaluated after 2014 were included.

RESULTS

Seven patients (six males and one female) were diagnosed with PAI caused by bilateral adrenal infiltrative disease at a median age of 54 (range 36-80) years. Duration of symptoms prior to the diagnosis of PAI and initiating treatment was 6 months (range 3 months-4 years). All patients demonstrated bilateral adrenal masses on adrenal imaging. The underlying diagnosis was confirmed by histopathology and included: bilateral adrenal metastases (lung and breast adenocarcinoma), diffuse large B-cell lymphoma, tuberculosis, cryptococcus, histoplasmosis, and, Erdheim-Chester disease.

CONCLUSION

In patients with newly diagnosed PAI, the differential diagnosis should include bilateral infiltrative adrenal disease, especially when testing for autoimmune adrenalitis is negative, or if there is clinical history suggesting another etiology. Patients who present with known bilateral adrenal infiltrative disease should be counseled and tested for PAI periodically, particularly if presenting with suggestive signs or symptoms.

The outcomes of adrenalectomy for solitary adrenal metastasis: A 17-year single-center experience

AIM

We aimed to analyze surgical outcomes of open or laparoscopic adrenalectomy for solitary adrenal metastasis and assess the factors influencing survival.

METHODS

We retrospectively reviewed our institutional clinicopathological database for cases of adrenalectomy for solitary adrenal metastasis from solid tumors between 2000 and 2017.

RESULTS

Twenty-five patients underwent open adrenalectomy (n = 11) or laparoscopic adrenalectomy (n = 14). The most common primary site was the lung (n = 7), followed by the kidney (n = 5), liver (n = 3), ovary (n = 2), soft tissue (n = 2), and six other sites. The majority of the patients (n = 19) had metachronous metastasis. The median tumor size was 3.1 cm (1-9 cm). With the median follow-up of 32 months (2-144 months), the median progression-free and overall survivals were 14 and 63 months, respectively. Multivariate analysis revealed that synchronous metastasis (hazard ratio [HR] = 7.5) and tumor size ≥ 4 cm (HR = 17.7) were significant prognostic factors for shorter overall survival. There was no significant difference for survival between the laparoscopic and open groups.

CONCLUSIONS

Adrenalectomy for solitary adrenal metastasis can be applied for selected patients with various types of malignancy. However, synchronous metastasis and tumor size ≥ 4 cm were prognostic factors for shorter overall survival.

Incidence of adrenal gland tumor as a second primary malignancy: SEER-based study

PURPOSE

Advances in cancer treatment achieved during the past decades have resulted in increased survival of most pediatric and adult patients that suffered from different adrenal tumor types. This article reviews the incidence and survival of adrenal gland tumors as second primary tumors, according to data from the Surveillance, Epidemiology, and End Results (SEER) database.

METHOD

The SEER 13 Registries Database from 1992 to 2013 was used. All primary cancer sites were selected using the Multiple Primary Standardized Incidence Ratios (MP-SIR) session.

RESULTS

Data for a total of 2,887,468 persons with cancer were reviewed. 117 of whom had suffered second primary adrenal tumors. The overall standardized incidence ratio (SIR) of adrenal gland tumor as a second primary was 1.49. A high incidence ratio of the event was also detected in specific primary tumor sites: hypopharynx (Observed/Expected(O/E) = 44.59); other endocrine tissue (including the thymus) (O/E=38.27); chronic myeloid leukemia (O/E=11.15); small intestine (O/E=8.86); liver (O/E=8.74); stomach (O/E=4.95); nodal NHL (O/E=3.79); kidney and renal pelvis (O/E=3.19); and breast (O/E=1.78).

CONCLUSION

The underlying shared mechanisms should be investigated between adrenal tumors and hypopharyngeal, endocrine and other tumors. Racial disparity is an important challenge in cancer treatment at US and should be taken into consideration in the design of cancer prevention programs. This could be achieved through follow-up programs at specialized national cancer networks, especially for rare tumors like adrenal gland.

Practical Approach to Adrenal Imaging

Various pathologies can affect the adrenal gland. Noninvasive cross-sectional imaging is used for evaluating adrenal masses. Accurate diagnosis of adrenal lesions is critical, especially in cancer patients; the presence of adrenal metastasis changes prognosis and treatment. Characterization of adrenal lesions predominantly relies on morphologic and physiologic features to enable correct diagnosis and management. Key diagnostic features to differentiate benign and malignant adrenal lesions include presence/absence of intracytoplasmic lipid, fat cells, hemorrhage, calcification, or necrosis and locoregional and distant disease; enhancement pattern and washout values; and lesion size and stability. This article reviews a spectrum of adrenal pathologies.

Isolated Synchronous Adrenal Lesions in Patients with Newly Diagnosed Extra-Adrenal Malignancies

Background:

This study focused on the etiology of patients with extra-adrenal primary malignancy in addition to isolated synchronous adrenal incidentalomas.

Methods:

Patients who were diagnosed as extra-adrenal primary malignancy and synchronous adrenal incidentalomas were enrolled from a single tertiary medical center from 2004 to 2014. Those with a history of malignancy or any extra-adrenal metastases at the time of diagnosis were excluded. Statistical analysis was performed to determine possible predictors for adrenal metastases.

Results:

The primary malignancies of hepatocellular carcinoma and lung cancer had higher rates of adrenal metastases than colon cancer and renal cell carcinoma. Significant predictors for adrenal metastasis were clinical T stage and adrenal mass diameters. Patients with stage T1/2 primary malignancies were more likely to have benign adrenal tumors than those with stage T3 or T4. The average adrenal mass diameters in the benign and metastatic groups were 2.87 and 4.97 cm, respectively (P = 0.001).

Conclusions:

Nearly 40% of the isolated synchronous adrenal incidentalomas in patients with newly diagnosed extra-adrenal malignancies proved to be metastases. In patients with large adrenal lesions, high mass density on computed tomography scans, or a primary malignancy at a high clinical T stage, the risk of adrenal metastasis was high.

Incidentally Detected Bilateral Adrenal Nodules in Patients Without Cancer: Is Further Workup Necessary?

OBJECTIVE

The purpose of this study was to determine the rate of malignancy in incidentally detected bilateral adrenal masses in patients with no known history of cancer.

MATERIALS AND METHODS

A retrospective search of CT reports of patients with incidentally detected bilateral adrenal nodules was performed from January 1, 2002, to January 1, 2014. Patients were excluded if they had a known cancer or suspected functioning adrenal tumor; 161 patients were included. Nodules were characterized as benign or malignant on the basis of imaging features at the index CT examination, imaging features at subsequent adrenal protocol CT or MRI, imaging stability for a minimum of 1 year, or clinical follow-up of a minimum of 2 years.

RESULTS

Mean nodule size was 1.8 cm (range, 0.7-4.9 cm). There were no cases of primary or secondary adrenal malignancy (95% CI, 0.00-0.023). The nodules diagnosed on index CT scans were 73 adrenal adenomas and two myelolipomas. Seventy-four nodules were subsequently characterized as adrenal adenomas on the basis of imaging findings. Of the 113 indeterminate nodules that had imaging follow-up, 111 were stable at the latest follow-up examination. One nodule grew 26% over 8.1 years, and the other grew 59% over 12.4 years. Clinical follow-up of patients with 60 indeterminate nodules revealed no evidence of adrenal malignancy.

CONCLUSION

No case of malignancy was found in 322 incidentally detected bilateral adrenal nodules at CT of patients without known cancer. Imaging follow-up of such lesions may be unnecessary.

Radiology of the adrenal incidentalomas. Review of the literature

The term "adrenal incidentaloma" is a radiological term. Adrenal incidentalomas are adrenal tumors discovered in an imaging study that has been obtained for indications exclusive to adrenal conditions (Udelsman 2001; Linos 2003; Bulow et al. 2006; Anagnostis et al. 2009). This definition excludes patients undergoing imaging testing as part of staging and work-up for cancer (Grumbach et al. 2003; Anagnostis et al. 2009). Papierska et al. (2013) have added the prerequisite that the size of a tumor must be "greater than 1cm in diameter", in order to be called incidentaloma. Although in the most cases these masses are non-hypersecreting and benign, they still represent an important clinical concern because of the risk of malignancy or hormone hyperfunction (Barzon et al. 2003). Th e adrenal tumors belong to the commonest incidental findings having been discovered (Kanagarajah et al. 2012).

Update on CT and MRI of Adrenal Nodules

OBJECTIVE

The objective of this article is to review the current role of CT and MRI for the characterization of adrenal nodules.

CONCLUSION

Unenhanced CT and chemical-shift MRI have high specificity for lipid-rich adenomas. Dual-energy CT provides comparable to slightly lower sensitivity for the diagnosis of lipid-rich adenomas but may improve characterization of lipid-poor adenomas. Nonadenomas containing intracellular lipid pose an imaging challenge; however, nonadenomas that contain lipid may be potentially diagnosed using other imaging features. Multiphase adrenal washout CT can be used to differentiate lipid-poor adenomas from metastases but is limited for the diagnosis of hypervascular malignancies and pheochromocytoma.

Practical Approach to Adrenal Imaging

Various pathologies can affect the adrenal gland. Noninvasive cross-sectional imaging is used for evaluating adrenal masses. Accurate diagnosis of adrenal lesions is critical, especially in cancer patients; the presence of adrenal metastasis changes prognosis and treatment. Characterization of adrenal lesions predominantly relies on morphologic and physiologic features to enable correct diagnosis and management. Key diagnostic features to differentiate benign and malignant adrenal lesions include presence/absence of intracytoplasmic lipid, fat cells, hemorrhage, calcification, or necrosis and locoregional and distant disease; enhancement pattern and washout values; and lesion size and stability. This article reviews a spectrum of adrenal pathologies.

Comparison of Quantitative MRI and CT Washout Analysis for Differentiation of Adrenal Pheochromocytoma From Adrenal Adenoma

OBJECTIVE

The purpose of this study was to use quantitative analysis to assess MRI and washout CT in the diagnosis of pheochromocytoma versus adenoma.

MATERIALS AND METHODS

Thirty-four pheochromocytomas (washout CT, 5; MRI, 24; both MRI and CT, 5) resected between 2003 and 2014 were compared with 39 consecutive adenomas (washout CT, 9; MRI, 29; both MRI and CT, 1). A blinded radiologist measured unenhanced attenuation, 70-second peak CT enhancement, 15-minute relative and absolute percentage CT washout, chemical-shift signal intensity index, adrenal-to-spleen signal intensity ratio, T2-weighted signal intensity ratio, and AUC of the contrast-enhanced MRI curve. Comparisons between groups were performed with multivariate and ROC analyses.

RESULTS

There was no difference in age or sex between the groups (p > 0.05). For CT, pheochromocytomas were larger (4.2 ± 2.5 [SD] vs 2.3 ± 0.9 mm; p = 0.02) and had higher unenhanced attenuation (35.7 ± 6.8 HU [range, 24-48 HU] vs 14.0 ± 20.9 HU [range, -19 to 52 HU]; p = 0.002), greater 70-second peak CT enhancement (92.8 ± 31.1 HU [range, 41.0-143.1 HU] vs 82.6 ± 29.9 HU [range, 50.0-139.0 HU ]; p = 0.01), lower relative washout CT (21.7 ± 24.7 [range, -29.3 to 53.7] vs 65.3 ± 22.3 [range, 32.9-115.3]; p = 0.002), and lower absolute washout CT (31.9 ± 42.8 [range, -70.6 to 70.2] vs 76.9 ± 10.3 [range, 60.3-89.6]; p = 0.001). Thirty percent (3/10) of pheochromocytomas had absolute CT washout in the adenoma range (> 60%). For MRI, pheochromocytomas were larger (5.0 ± 4.2 vs 2.0 ± 0.7 mm; p = 0.003) and had a lower chemical-shift signal intensity index and higher adrenal-to-spleen signal intensity ratio (-3.5% ± 14.3% [range, -56.3% to 12.2%] and 1.1% ± 0.1% [range, 0.9-1.3%] vs 47.3% ± 27.8% [range, -9.4% to 86.0%] and 0.51% ± 0.27% [range, 0.13-1.1%]) (p < 0.001) and higher T2-weighted signal intensity ratio (4.4 ± 2.4 vs 1.8 ± 0.8; p < 0.001). There was no statistically significant difference in contrast-enhanced MRI AUC (288.9 ± 265.3 vs 276.2 ± 129.9 seconds; p = 0.96). The ROC AUC for T2-weighted signal intensity ratio was 0.91 with values greater than 3.8 diagnostic of pheochromocytoma.

CONCLUSION

In this study, the presence of intracellular lipid on unenhanced CT or chemical-shift MR images was diagnostic of adrenal adenoma. Elevated T2-weighted signal intensity ratio was specific for pheochromocytoma but lacked sensitivity. There was overlap in all other MRI and CT washout parameters.

Management of suspected adrenal metastases at 2 academic medical centers

BACKGROUND

The optimal management of suspected adrenal metastases remains controversial.

METHODS

This is a retrospective bi-institutional review of 37 patients who underwent adrenalectomy for suspected adrenal metastasis between 2001 and 2014.

RESULTS

Three (8%) patients had benign adenomas on final pathology. At a median follow-up of 21 months, 7 (32%) patients were alive with no evidence of disease and 7 (32%) were alive with recurrent disease. Recurrence-free survival (RFS) was 8 months; decreased RFS was associated with positive margins and size ≥6 cm. Overall survival (OS) was 29 months; decreased OS was associated with capsular disruption. There were no differences in RFS or OS by surgical approach.

CONCLUSIONS

The favorable OS supports adrenalectomy in select patients with suspected adrenal metastases. Minimally invasive adrenalectomy is safe and effective, but the surgical approach should be based on the ability to achieve a margin-negative resection with avoidance of capsular disruption.

CLINICAL OUTCOMES IN ADRENAL INCIDENTALOMA: EXPERIENCE FROM ONE CENTER

OBJECTIVE

To investigate the outcome in patients with adrenal incidentaloma (AI).

METHODS

A retrospective evaluation of 637 patients with AI referred to a tertiary center over 8 years. Radiologic and hormonal evaluations were performed at baseline. Follow-up imaging was carried out if necessary, and hormonal evaluation was performed at 24 months according to national guidelines.

RESULTS

The mean age was 62.7 ± 11.6 years, and the mean AI size was 25.3 ± 17.0 mm at presentation. Hormonal evaluation revealed that 85.4% of all tumors were nonfunctioning adenomas, 4.1% subclinical Cushing syndrome (SCS), 1.4% pheochromocytoma, 1.4% primary hyperaldosteronism, 0.8% Cushing syndrome, 0.6% adrenocortical carcinoma, 0.3% congenital adrenal hyperplasia, 2.2% metastasis to adrenals, and 3.8% other lesions of benign origin. Bilateral tumors were found in 11%, and compared to unilateral tumors, SCS was more prevalent. Only 2 cases were reclassified during follow-up, both as SCS, but neither had had a dexamethasone suppression test performed at initial work-up. In patients diagnosed with an adrenal metastasis, 92.9% were deceased within 2 years. Excluding those with malignant tumors, 12.9% of patients died during the study period of up to 11 years due to other causes than adrenal.

CONCLUSION

Most AIs were benign, but a small fraction of tumors were functional and malignant. The prognosis of patients with adrenal metastasis was extremely poor, but otherwise, the mortality rate was similar to that for the general population. Follow-up of AIs <4 cm with an initial nonfunctional profile and benign radiologic appearance appears unwarranted, but screening for congenital adrenal hyperplasia should be considered.

Adrenal incidentaloma: evaluation and management

Adrenal incidentalomas are adrenal masses discovered incidental to imaging studies performed for reasons unrelated to adrenal pathology. Although most adrenal incidentalomas are non-functioning benign adenomas, their increasing prevalence presents diagnostic and therapeutic challenges. The assessment of adrenal incidentalomas is aimed at deciding whether or not the tumour should be surgically removed. Adrenalectomy is indicated for phaeochromocytoma, other symptomatic hormone-secreting tumours and those with a high risk of malignancy. Biochemical screening for tumour hypersecretion is mandatory in all adrenal incidentalomas, since hormone secreting tumours may be clinically silent. The diagnosis of phaeochromocytoma is of paramount importance because of its life-threatening complications. Non-functioning adrenal incidentalomas need assessment for risk of malignancy, and this is based on the size of the tumour and its imaging characteristics. An observational policy with periodic radiological and biochemical reassessment is pursued in patients with non-functioning incidentalomas with low malignancy risk. The duration and frequency of reassessment remains unclear, as the natural history of adrenal incidentalomas has yet to be clearly defined, and there is a lack of controlled studies comparing surgical intervention with observation. However, the possibility of acquiring autonomous hypersecretion or conversion to malignancy in an incidentaloma diagnosed to be a benign non-functioning lesion is very low, and most patients may be safely discharged after an initial follow-up period of 2 years.

Imaging of the adrenal gland lesions

With the steep increase in the use of cross-sectional imaging in recent years, the incidentally detected adrenal lesion, or "incidentaloma", has become an increasingly common diagnostic problem for the radiologist, and a need for an approach to classifying these lesions as benign, malignant or indeterminate with imaging has spurred an explosion of research. While most incidentalomas represent benign disease, typically an adenoma, the possibility of malignant involvement of the adrenal gland necessitates a reliance on imaging to inform management decisions. In this article, we review the literature on adrenal gland imaging, with particular emphasis on computed tomography, magnetic resonance imaging, and photon-emission tomography, and discuss how these findings relate to clinical practice. Emerging technologies, such as contrast-enhanced ultrasonography, dual-energy computed tomography, and magnetic resonance spectroscopic imaging will also be briefly addressed.

Oncological applications of dual-energy computed tomography imaging

Dual-energy computed tomography (DECT) imaging is a promising method used in oncology for accurate detection/diagnosis of malignant and benign lesions. Use of dual-energy spectral, weighted average, color-coded map, and virtual unenhanced images provides increased visual detection and easy lesion delineation. Lesion detectability, sensitivity, and conspicuity are significantly improved using DECT. Material characterization and decomposition are promising using DECT. Both anatomical and functional information related to oncology can be provided by DECT using single contrast-enhanced CT.

Adrenal imaging (Part 2): Medullary and secondary adrenal lesions

Adrenal malignancies can be either primary adrenal tumors or secondary metastases, with metastases representing the most common malignant adrenal lesion. While imaging cannot always clearly differentiate between various adrenal malignancies, presence of certain imaging features, in conjunction with appropriate clinical background and hormonal profile, can suggest the appropriate diagnosis. The second part of the article on adrenal imaging describes adrenal medullary tumors, secondary adrenal lesions, bilateral adrenal lesions, adrenal incidentalomas and provides an algorithmic approach to adrenal lesions based on current imaging recommendations.

Incidental Adrenal Nodules and Masses: The Imaging Approach

Adrenal nodules are detected with increasing frequency. The National Institute of Health (NIH), American College of Radiology (ACR), and the American Association of Clinical Endocrinologists and American Association of Endocrine Surgeons (AACE/AAES) have produced guidelines for the management of incidental adrenal nodules. This review provides a summary of the consensus radiologic approach to these nodules.

Prognostic factors for recurrence-free and overall survival after adrenalectomy for metastatic carcinoma: a retrospective cohort pilot study

BACKGROUND

The survival benefits of adrenalectomy (ADx) in the setting of metastatic cancer and prognostic factors for recurrence-free (RFS) and overall survival (OS) after adrenalectomy for metastatic carcinoma are still under debate. We evaluated the impact of clinicopathological variables on RFS and OS after ADx for metastatic carcinoma in patients with primary cancer.

METHODS

A total of 32 patients undergoing ADx for metastatic cancer between 2004 and 2012 at two tertiary medical centers. Metastases were regarded as synchronous (<6 months) or metachronous (≥6 months) depending on the interval after primary surgery. Associations of perioperative clinicopathologic variables with RFS and OS were analyzed using Cox regression models.

RESULTS

In total, 32 patients received ADx for metastatic primary tumors located in the lung (n = 11), colon (n = 4), liver (n = 5), stomach (n = 3), kidney (n = 4), pancreas (n = 2), glottis, esophagus, cervix, and ovary (n = 1 each). The overall recurrence rate after adrenalectomy was 62.5% (n = 20). By univariate analysis, C-reactive protein, inflammation-based prognosis score, and adrenalectomy for curative intent were associated with RFS and OS. Independent prognostic factors for shorter RFS were operative method (laparoscopy HR 4.68, 95% CI 1.61-13.61, p = 0.005) and inflammation-based prognostic score (HR 11.8, 95% CI 2.50-55.7, p = 0.002). For shorter OS, synchronous metastasis (HR 3.05, 95% CI 1.07-11.94, p = 0.048) and inflammation-based prognostic score (HR 6.65, 95% CI 1.25-35.23, p = 0.026) were identified as independent prognostic factors.

CONCLUSIONS

Our pilot study suggests that synchronous disease and inflammation-based prognostic score are significant prognostic factors for survival and should be considered when performing ADx for metastatic diseases.

[Adrenal incidentalomas]

Adrenal incidentalomas are found in approximately 2-3% of abdominal CT-scan examinations. A key issue is to determine whether the incidentaloma is neoplastic or responsible for endocrine hypersecretion, two situations in which surgical excision is recommended. Candidate incidentalomas for surgery include hypersecreting tumors (pheochromocytomas, Cushing's adenoma, Conn's adenoma) and adrenocortical carcinomas. The majority of adrenal incidentalomas are non-secreting cortical adenomas and lesions to remove account for less than 5% of adrenal incidentalomes. The pathological consequences of "subclinical" cortisol-secreting adenomas responsible for mild hypercortisolism and whether or not these tumors should be removed remain debatable.

Surgical management of adrenal metastases

In the presence of a history of cancer, adrenal masses are commonly, but not exclusively, metastases. Depending upon the status of the patient's ongoing cancer therapy, overall tumor burden, and performance score, adrenalectomy is a viable treatment option. Herein we review the prevalence, diagnostic evaluation, and selection for surgical treatment of adrenal metastases. Additional attention is paid to recent data supporting the safety and oncologic efficacy of laparoscopic adrenalectomy.

Bilateral adrenal incidentalomas: a case report and review of diagnostic challenges

Incidentally discovered adrenal masses (incidentalomas) are common and present challenges both in diagnosis and management. When incidentally discovered adrenal masses are bilateral, a refined diagnostic approach is warranted since bilateral disease is more likely to be pathologic. We review a case of a 34-year-old man with incidentally discovered bilateral adrenal nodules. A comprehensive diagnostic strategy led to the diagnosis of bilateral pheochromocytoma caused by von Hippel-Lindau syndrome. He was successfully treated with bilateral laparoscopic adrenalectomy and has recovered well. While the initial diagnostic approach is similar to the unilateral incidentaloma, additional testing and/or genetic testing should be considered in the case of the bilateral adrenal mass.

Dual-energy CT applications in the abdomen

OBJECTIVE

The purpose of this article is to give a brief overview of the technical background of dual-energy CT (DECT) imaging and to review various DECT applications in the abdomen that are currently available for clinical practice. In a review of the recent literature, specific DECT applications available for abdominal organs, liver, pancreas, kidneys including renal stones, and adrenal glands, will be discussed in light of reliability and clinical usefulness in replacing true unenhanced imaging, increased lesion conspicuity, iodine extraction, and improved tissue/material characterization (e.g., renal stone composition). Radiation dose considerations will be addressed in comparison with standard abdominal imaging protocols.

CONCLUSION

Modern DECT applications for the abdomen expand the use of CT and enable advanced quantitative methods in the clinical routine on the basis of differences in material attenuation observed by imaging at two different distinct photon energies.

Bilateral primary adrenal lymphoma presenting with adrenal insufficiency

Lymphoma may occasionally involve the adrenal glands, but primary adrenal lymphoma (PAL) is very rare and only few cases have been reported. We present a case of a 60-year-old, otherwise healthy, woman, with bilateral PAL presenting with adrenal insufficiency. The patient responded initially upon administration of large doses of intravenously hydrocortisone with total remission of symptoms. An abdominal computerized tomography scan demonstrated bilateral adrenal lesions but did not demonstrate any other pathology. Since metastatic malignant disease was suspected a positron-emission-tomography scan was performed only showing significant uptake in the adrenal glands. Endocrine evaluation did not reveal abnormal function of any hormonal system and the patient was scheduled for bilateral adrenalectomy. However the clinical condition deteriorated rapidly and the patient was readmitted to hospital before surgery was performed. A new computerized tomography scan showed rapid progression of disease with further enlargement of the adrenal masses and both pulmonary and hepatic metastasis. Needle biopsy was performed but the patient refused further treatment and died before a diagnosis was obtained. The immuneohistochemical diagnosis was large B-cell lymphoma. This case should remind clinicians that PAL may be a cause of bilateral adrenal incidentaloma especially if the patient presents with adrenal insufficiency.

Adrenal imaging: a comprehensive review

The discovery of an incidental adrenal mass (adrenal incidentaloma) continues to rise with the increasing use of cross-sectional imaging. Although most adrenal lesions are benign and asymptomatic, radiologists should guide evaluation of these lesions, whether benign or malignant. This article reviews the various imaging techniques used to evaluate adrenal masses and their relative strengths and weaknesses. It focuses on the most prevalent adrenal pathologies and their typical imaging characteristics, and concludes with a brief discussion of developing techniques, including diffusion-weighted imaging and dual-energy CT.

Dual-energy CT for characterization of the incidental adrenal mass: preliminary observations

OBJECTIVE

The purpose of our study was to evaluate the accuracy of virtual unenhanced images reconstructed from contrast-enhanced dual-energy CT for the differentiation of incidental adrenal masses in comparison with standard unenhanced CT.

MATERIALS AND METHODS

One hundred-forty patients (mean age, 74±9 years) underwent unenhanced and contrast-enhanced CT of the abdomen, the latter acquired with dual-energy for reconstruction of virtual unenhanced images. Two blinded and independent readers (R1 and R2) measured attenuation of each incidental adrenal mass on standard unenhanced and virtual unenhanced images using an optimized dual-energy three-material decomposition algorithm.

RESULTS

Fifty-one incidental adrenal masses were found in 42 of 135 patients (31%); 39 incidental adrenal masses were ≥1 cm. On the basis of unenhanced CT, 29 of 51 incidental adrenal masses and 22 of 39 incidental adrenal masses≥1 cm were classified as benign (HU<10). Virtual unenhanced image quality was rated as good or with mild impairment (2.45±0.83 for R1, 2.45±0.99 for R2). Image noise was 12.7±3.6 HU in unenhanced images and 8.8±2.0 HU in virtual unenhanced images (p<0.001). There was no significant difference in incidental adrenal mass attenuation between unenhanced and virtual unenhanced images for all incidental adrenal masses (5.9±21.0 HU vs 7.0±20.6 HU, p=0.48) and for those≥1 cm (6.6±18.5 HU vs 7.9±18.3 HU, p=0.87). Sensitivity, specificity, and accuracy of virtual unenhanced images for the characterization of incidental adrenal masses as probably benign were 76%, 82%, and 78% for R1 and 79%, 95%, and 86% for R2, respectively. For incidental adrenal masses≥1 cm, sensitivity, specificity, and accuracy increased to 95%, 100%, and 97% for R1 and 91%, 100%, and 95% for R2.

CONCLUSION

Reconstruction of virtual unenhanced images from contrast-enhanced dual-energy CT of the abdomen allows the characterization of the incidental adrenal masses with a good accuracy compared with standard unenhanced CT, with the most favorable results in incidental adrenal masses measuring≥1 cm.

Characterization of adrenal lesions with 1.5-T MRI: preliminary observations on comparison of three in-phase and out-of-phase gradient-echo techniques

OBJECTIVE

The purpose of this study was to use previously described quantitative evaluation methods to compare the performance of 3D gradient-recalled echo (GRE) and magnetization-prepared (MP) GRE in-phase and out-of phase sequences with standard 2D GRE technique in the characterization of adrenal lesions.

MATERIALS AND METHODS

The study sample consisted of 44 consecutively registered patients (22 men, 22 women; mean age, 59.1 ± 11.6 years) with 50 adrenal lesions who underwent standard abdominal MRI that included in-phase and out-of-phase 2D GRE (n = 41), 3D GRE (n = 35), MP GRE (n = 36), or a combination of these techniques. The adrenal signal intensity (SI) index and adrenal-to-spleen, adrenal-to-liver, and adrenal-to-muscle SI ratios of each lesion were calculated and compared for the three techniques by independent samples Student t test. The area under the receiver operating characteristic (ROC) curve (AUC) for each evaluation method was determined, and comparisons of independent ROC curves were performed for all sequences.

RESULTS

For all sequences, the mean adrenal SI index and SI ratios of adenomas and nonadenomas differed significantly (p < 0.001). For the 3D GRE and MP GRE techniques, adrenal SI index and modified adrenal-to-spleen ratio, respectively, had the larger AUCs, but the difference was not statistically significant. Different thresholds for the three techniques were recommended for discriminating adenoma from nonadenoma.

CONCLUSION

The results of characterization of adrenal lesions with MP GRE and 3D GRE in-phase and out-of-phase MRI techniques are comparable to those obtained with the reference standard 2D GRE technique. Different thresholds should be selected according to the in-phase and out-of-phase techniques used and for the various evaluation methods.

Incidentally discovered adrenal mass

Adrenal masses are common incidental findings on cross-sectional imaging. Most of these masses are benign, and adenomas are the most common entity. Several imaging studies allow accurate diagnosis of these masses, separating inconsequential benign masses from the lesions that require treatment. This article discusses contemporary adrenal imaging and the optimal algorithm for the workup of incidentally detected adrenal masses.

Laparoscopic adrenalectomy: balancing the operative indications with the technical advances

Laparoscopic adrenalectomy contributed significantly to reduction of morbidity and improvement of postoperative patient recovery time. The adoption of this technique had substantial impact on the management of adrenal incidentalomas. Although laparoscopic adrenalectomy should be in general avoided for known primary adrenal cancers, it is appropriate for metastasectomy of isolated adrenal metastatic disease.

Natural course of benign adrenal incidentalomas in subjects with extra-adrenal malignancy

Patients with extra-adrenal malignancies are diagnosed increasingly with benign adrenal tumors, as well as non-oncology subjects. We aimed to demonstrate the natural course of adrenal adenomas in terms of mass size and hormonal status in oncology and non-oncology subjects. We also compared the characteristics and behavior of adrenal adenomas with adrenal malignancies. In our registry of adrenal tumors (n = 335), we prospectively evaluated 29 oncology subjects (EAM+) and age, gender, and follow-up duration matched 110 non-oncology subjects (EAM-) with adrenal adenomas. Median follow-up was 24 months. We also included 16 subjects with adrenal malignancies (primary; 3 and metastasis; 13). Tumor size was followed-up with CT or MRI at 6th and 12th months and annually in subsequent visits. Hormonal assessment was repeated at the 6th month after the initial visit and annually in subsequent visits. Initial tumor size, mean increase in tumor size, and number of subjects who showed mass enlargement or developed subclinical Cushing Syndrome were comparable (P > 0.05) between EAM+ and EAM- groups. Subjects with malignant adrenal tumors were older (P = 0.06), had larger tumors at presentation (P < 0.001), and showed mass enlargement during a shorter follow-up duration (P < 0.001). Oncology subjects with adrenal adenomas featured similar baseline and follow-up parameters in terms of mass enlargement and development of subclinical Cushing Syndrome when compared with non-oncology subjects. Malignant adrenal tumors were characterized with large, rapidly growing tumors of older ages. Conservative approach can be suggested to oncology subjects for adrenal adenomas unless clinical and radiological suspicion of adrenal malignancy is present.

Incidental adrenal lesions: principles, techniques, and algorithms for imaging characterization

Incidental adrenal lesions are commonly detected at computed tomography, and lesion characterization is critical, particularly in the oncologic patient. Imaging tests have been developed that can accurately differentiate these lesions by using a variety of principles and techniques, and each is discussed in turn. An imaging algorithm is provided to guide radiologists toward the appropriate test to make the correct diagnosis.