Corticomedullary mixed tumor of the adrenal gland

Mixed Corticomedullary Tumor of the Adrenal Gland: A Case Report and Literature Review

Adrenal mixed corticomedullary tumors (MCMTs) are composed of an admixture of cortical and medullary cells. Owing to the presence of two distinct components of different embryonic lineage, these tumors are extremely rare. Less than 30 tumors of this type have been reported to date. MCMTs have varied presentation including hypertension, Cushing syndrome or even as adrenal incidentalomas. Also noted is a slightly higher female preponderance. We report a case of a 26-year-old female who was evaluated for uncontrolled hypertension. A renal ultrasound followed by MRI abdomen revealed a 9.3 × 8.1 × 7.0 cm partially cystic, partially solid enhancing mass in the region of/replacing the left adrenal gland. Hormonal work-up was significant for elevated catecholamines concerning pheochromocytoma. She underwent laparoscopic left adrenalectomy, with adequate pre-operative adrenergic blockade. Histology and immunochemical testing were consistent with a mixed corticomedullary tumor. She was monitored annually for recurrence of the tumor. We also performed a comprehensive review of literature of the cases published so far to the best of our knowledge.

A Rare Case: Adrenal Corticomedullary Mixed Tumor With Elements of Pheochromocytoma, Cortical Adenoma, and Ganglioneuroma Cells

Background/Objective

Adrenal corticomedullary mixed tumor (CMMT) are extremely rare single adrenal tumor masses containing a mixture of adrenal cortical adenoma and pheochromocytoma cells.

Case Report

A 52-year-old woman presented with clinical and biochemical evidence of cortisol and catecholamine excess and was found to have an adrenal CMMT with intermixed chromaffin, cortical adenoma, and ganglioneuroma components. She underwent a successful unilateral adrenalectomy with subsequent improvement in her symptoms.

Discussion

We report the first case of a patient with a CMMT that had symptoms of both catecholamine and cortisol excess from her tumor. Typically, patients with similar tumors have signs of cortisol excess; however, the pheochromocytoma portion is clinically silent. Although most CMMT contain 2 distinct cell types, this is the third ever described case of a single adrenal CMMT containing 3 unique cellular components: (1) intermixed chromaffin, (2) cortical adenoma, and (3) ganglioneuroma cells.

Conclusion

Our understanding of these rare tumors is limited, and this case serves to broaden our knowledge about their clinical, biochemical, and pathologic features.

Current Understanding of "Mixed Corticomedullary Adrenal Tumor" and an Insight into Genomic Profiling

BACKGROUND

Malignant mixed corticomedullary adrenal tumors (MCMTs) are extremely rare, with limited cases reported in the literature. The pathophysiology of malignant MCMTs is not well understood; the most prevailing theories are that it is a composite tumor of embryologically derived mesodermal (adrenal cortex) and neural crest (medulla) origin, perpetuating as two distinct cell lines forming a singular mass. Clinical features and laboratory diagnosis are associated with hypersecretions of the adrenal cortex and medulla. Surgical resection is curative in an isolated tumor. We reviewed and compared cases in the literature highlighting the pathogenesis and genetics of benign and malignant MCMT.

METHODS

Comprehensive literature analysis was conducted on PubMed and all the cases of mixed corticomedullary adrenal tumor published in English were included.

RESULTS

Most patients were female (73.1%) with a median age of 49 in women and 50 in men. Surgery was performed in all patients, and in four patients with malignant disease, chemotherapy was used as well. Clinically, most patients presented with hypertension (69%) followed by Cushing syndrome (42%) and diabetes (19%). Tumors often produced cortisol (74%), catecholamines (50%), and adrenocorticotrophic hormone (ACTH) (38%), with lower incidence of aldosterone- (7%) or dopamine (4%)-producing tumors. Immunohistochemical staining of 96% of cases showed Chromogranin-A (73%) and Synaptophysin (62%), followed by Inhibin-α (50%), Melan-A (31%), and S-100 (23%). Of the reported four cases with malignant disease, three showed a Ki-67 index of 40-50% with one showing less than 5%.

CONCLUSION

Mixed corticomedullary adrenal tumors rarely present as a malignant disease requiring chemotherapy. Most MCMTs confer a good prognosis and respond well to surgical resection, though their pathogenesis is largely up to speculation because of limited data. Current theories regarding MCMT pathogenesis should be investigated further with genetic testing. Future research on MCMT may provide ways to guide physician diagnosis and subsequent treatment for refractory cases.

Corticomedullary Mixed Tumor of the Adrenal Gland with Apparent 18F-Fluorodeoxyglucose Activity But No 68GA-DOTATATE Uptake on Positron Emission Tomography/Computed Tomography

Corticomedullary mixed tumor (CMT) is a single adrenal tumor mass composed histologically by an admixture of adrenal cortical and medullary cells. It is a rare condition, with approximately 20 cases reported to date. To our knowledge, the positron emission tomography (PET) imaging findings of this mostly benign tumor have not been reported in the literature. We present a case of CMT who was evaluated with both 18F-fluorodeoxyglucose (18F-FDG) and 68Ga-DOTATATE. The hypermetabolic tumor seen on 18F-FDG PET/computed tomography scan showed no abnormal uptake by 68Ga-DOTATATE.

Mixed corticomedullary tumor of the adrenal gland

Mixed corticomedullary tumor (MCMT) of the adrenal gland is an extremely rare tumor characterized by an admixture of steroidogenic cells and chromaffin cells in a single tumor mass simultaneously producing adrenocortical hormones and catecholamines; it is associated with ectopic adrenocorticotropic hormone (ACTH) in some cases. We reviewed and summarized clinicopathological data of 28 MCMTs, including four metastatic tumors in 26 previous reports. These reports included 21 females and 7 males, and the average tumor sizes were 4.8 ± 2.5 cm and 12.6 ± 6.4 cm in the non-metastatic and metastatic groups, respectively (P<0.001). The clinical manifestations and laboratory data were as follows: Cushing or subclinical Cushing syndrome, 58% (14/24); hypertension, 71% (17/24); elevated adrenocortical hormones, 75% (18/24); elevated catecholamines, 75% (18/24); and ectopic ACTH, 71% (10/14). All four patients with metastatic MCMTs had poor prognoses and elevated adrenocortical hormone levels; however, only two patients had elevated catecholamine levels. Immunohistochemistry was essential for the pathologic diagnosis of MCMTs. In this study, using an improved technique, we detected ectopic ACTH-producing cells in the same paraffin-embedded sections reported to be negative in our previous reports. As MCMT is composed of cells with embryologically different origins, its pathogenesis has been explained by various hypotheses. We compared MCMT to the adrenal gland of birds and the early stage of human fetuses, in which nests of chromaffin cells and steroidogenic cells admix without the formation of cortex and medulla. MCMT is characterized by the immaturity of organogenesis and might be classified as an adrenal embryonal tumor.

Mixed Corticomedullary Tumor Accompanied by Unilateral Aldosterone-Producing Adrenocortical Micronodules: a Case Report

Mixed corticomedullary tumors (MCMTs) are rare and comprise medullary and cortical cells in a single adrenal tumor. The mechanisms underlying their development have not been fully elucidated. Here, we report a case of MCMT in a 42-year-old woman. Based on the preoperative clinical findings, the patient was diagnosed as having a pheochromocytoma with subclinical Cushing syndrome. Postoperative pathological diagnosis revealed that the tumor demonstrated morphologically distinct medullary and cortical components, which produced catecholamines and cortisol, respectively. Hybrid tumor cells producing both catecholamines and cortisol were not detected. Adrenocorticotropin (ACTH)-positive tumor cells were identified to be present in the pheochromocytoma. This ectopic production of ACTH can contribute to an autonomous cortisol production in a paracrine manner. In addition, micronodules producing aldosterone were detected in the adrenal tissue adjacent to the tumor. The simultaneous development of these 2 lesions may not be correlated with each other; however, this case confirms the importance of a detailed histopathological examination of the adrenal lesions harboring complicated hormonal abnormalities by providing pivotal and indispensable information on their pathogenesis and the possible interaction of the hormones produced in the adrenal gland.

Adrenal Vein Cortisol to Metanephrine Ratio for Localizing ACTH-Independent Cortisol-Producing Adenoma: A Case Report

Context

Finding the source of adrenocorticotropic hormone (ACTH)-independent cortisol-producing adenoma in the patients with subclinical Cushing syndrome (SCS) and bilateral adrenal nodules is sometimes challenging. Computed tomography (CT) and positron emission tomography are helpful, but adrenal venous sampling (AVS) is the gold standard approach. However, interpretation of AVS is important to improve the accuracy of decision-making for surgery. We report a case and review of the literature to assess the benefit of using adrenal vein cortisol to metanephrine ratio to determine the source of cortisol production in SCS and bilateral nodules.

Evidence Acquisition

Three authors searched PubMed for data on patients with SCS who had AVS procedure and measurements of cortisol and catecholamines.

Case Description

A 51-year-old woman with SCS and hypertension crisis presented to our clinic. Paraclinical investigations revealed that she had an ACTH-independent cortisol-producing adenoma and her CT scan showed bilateral adrenal nodules. After AVS, cortisol (high to low) lateralization ratio could not determine the source of cortisol production but the cortisol to metanephrine ratio localized the source to the left side, which included the larger nodule according to CT measurements. Left adrenalectomy led to clinical and paraclinical improvement.

Conclusion

There is a possibility of co-secretion of other steroids accompanied with cortisol in the setting of ACTH-independent SCS. Moreover, cortisol measurement alone and interpretation of AVS results based on cortisol values may not help lateralizing the source of cortisol production with bilateral adrenal nodules. Therefore, we suggest applying cortisol to metanephrine ratio with the same gradient (gradient > 2.3, highest to lowest concentration) when the source of cortisol production cannot be determined by cortisol lateralization ratio.

Black adrenal adenoma causing subclinical Cushing's syndrome complicated with pheochromocytoma

INTRODUCTION

The development of adrenocortical adenoma and pheochromocytoma within the same adrenal gland is very rare. Furthermore, no reports have described coincident black adrenal adenoma and pheochromocytoma. We herein report a rare case of coincident black adrenal adenoma and pheochromocytoma in the same adrenal gland.

CASE PRESENTATION

A 71-year-old Japanese woman was hospitalized because a right adrenal tumor had been incidentally found by computed tomography. She was diagnosed with subclinical Cushing's syndrome and underwent laparoscopic right adrenalectomy. The tumor contained two adrenal nodules. The cut surface of the larger nodule was brownish-black on macroscopic examination. Pathological studies revealed coincident black adrenal adenoma and pheochromocytoma.

CONCLUSION

To the best of our knowledge, this is the first report of coincident black adrenal adenoma causing subclinical Cushing's syndrome and pheochromocytoma in the same adrenal gland. The mechanism of this rare scenario is unclear, and further study is necessary.

Adrenal Corticomedullary Mixed Tumor Associated With the FGFR4-G388R Variant

Adrenal corticomedullary mixed tumors (CMMTs) are extremely rare; with only 20 cases being reported to date, the pathogenesis has remained elusive. A 31-year-old woman developed gestational hypertension with psychiatric disturbances persistent to postpartum and was diagnosed with pheochromocytoma, for which adrenalectomy was performed. Histological findings showed mixed adrenocortical adenoma and pheochromocytoma. Double immunostaining of inhibin and INSM1 (insulinoma-associated protein 1) showed that the 2 tumor components had distinct functional properties. Exome analysis of peripheral leukocytes and tumor (singular, as anatomically it is only 1 mass) revealed a homozygous germline FGFR4-G388R variant. As a readout of the variant, serine phosphorylation of signal transducer and activator of transcription 3 (STAT3) was detected only in the nucleus of adrenocortical adenoma component but not in the pheochromocytoma component. No tyrosine phosphorylation of STAT3 was detected. We report a case of CMMT with the germline FGFR4-G388R variant. Although additional studies are required, our immunohistochemical analysis suggests that the variant may play a role in the development of the adrenocortical component within the pheochromocytoma, leading to CMMT.

From ACTH-Dependent to ACTH-Independent Cushing's Syndrome from a Malignant Mixed Corticomedullary Adrenal Tumor: Potential Role of Embryonic Stem Cells

Objective

To report the immunohistochemical and molecular evaluation of a patient with ectopic ACTH syndrome (EAS) from a MCAT which has single cells with features of both 96 medullary and cortical differentiation. Case Description and Methods. A 16-year-old woman presented with severe EAS and a large right MCAT composed of ACTH-secreting cells resembling pheochromocytoma and another lineage similar to adrenal carcinoma. Immunohistochemistry (IHC) showed positivity for medullary (ACTH, chromogranin A, synaptophysin, and PS-100) and epithelial components (inhibin, melan-A, and calretinin). Embryonic stem cell markers were evaluated using RT/PCR and immunofluorescence. After initial surgery, the tumor recurred shifting to rapidly progressive ACTH-independent liver metastasis.

Results

Histopathology and IHC revealed two distinct and intermingled cellular patterns, while some cells immunostained for both medullary and cortical markers. Demonstration of all stem cell biomarkers by RT/PCR and immunofluorescence was predominantly localized to the nucleus, whereas SOX2 immunoreactivity was evident in the cytoplasm as well.

Conclusion

The expression of cancer stem cell biomarkers points towards the involvement of primitive embryonic cells as the origin of this neoplasm and maybe to the clinically aggressive and biochemically changing behavior.

Corticomedullary mixed tumour resembling a small adrenal gland-involvement of cancer stem cells: case report

BACKGROUND

Adrenal corticomedullary mixed tumours are very rare. Its mechanism is rarely reported. Here we report the first case of a corticomedullary mixed tumour resembling a "small adrenal gland" with distinct arrangement of the cortical and medullary layers. We further hypothesize regarding the tumorigenic mechanism of this tumour.

CASE PRESENTATION

A 58-year man had been diagnosed with diabetes and hypertension for 3 years. His 24-h urine vanillylmandelic acid (VMA) levels were slightly elevated. An abnormal circadian cortisol rhythm was noted, and his cortisol levels were not suppressed by dexamethasone. Abdominal computed tomography (CT) revealed a right adrenal gland lesion (diameter, 30 × 38 mm), while an enhanced CT showed enhancement and hypervascularization. The tumour was positive for adrenocorticotropic hormone, chromogranin A (CGA), and steroidogenic factor-1 (SF-1) on the tumour surface. Acetaldehyde dehydrogenase 1(ALDH1), CD44, CD133, Nestin, Nerve growth factor receptor (NGFR), and Sex determining region y-box 9(SOX9) staining were positive. Although administration of medications for diabetes and hypertension was stopped until surgery was performed, the blood sugar level and blood pressure were maintained after surgery.

CONCLUSIONS

This is the first report about a possible mechanism by which cancer stem cells induce adrenal corticomedullary tumours.

Mixed corticomedullary adrenal carcinoma - case report: Comparison in features, treatment and prognosis with the other two reported cases

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Adrenal incidetaloma could be mixed tumor, and should be considered in every case.

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Radiological signs play an important rules in differentiate malignant from benign adrenal tumor.

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Complete immunohistochemical study is necessary to confirm pheochromocytoma that presents normally in the clinic.

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Additional reported cases and clinical trials are needed to put more effective treatment plans for Mixed corticomedullary adrenal carcinoma.

Introduction

Adrenal corticomedullary adenoma was reviewed in many cases in PubMed Library, While the coincidence corticomedullary adrenal carcinoma in the same gland was just described in two cases in the medical literature. Our case is the third to be reported and was treated with surgery and adjuvant chemotherapy and followed for two years.

Presentation of case

A 50-year-old man suffered from a mass effect in the left abdominal side. While the laboratory showed a mild elevation in the levels of both serum cortisol and 24 h urine cortisol, radiological images were highly suggested an adrenal malignant tumor without metastasis. At surgery a 22 cm sized mass was completely resected. Immunohistochemical study identified expression of both adrenocortical carcinoma and pheochromocytoma markers.

Discussion

Cases of coincidence corticomedullary tumor have been published in many reviews, cortical and/or medulllary hypersecretion were not always detected preoperatively by biochemical tests.

Mixed corticomedullary carcinoma are exceedingly rare, we came across three reported cases in medical literature, in one case laboratory tests confirmed both cortical and medulla hypersecretion, while the two others detected only cortical hypersecretion. The final diagnosis was always confirmed by immunohistochemical staining.

Conclusion

It could be noted that this is the first comparison of presentation, diagnosis, treatments and follow-up of the three cases of Mixed corticomedullary carcinoma. This could contribute to understanding the behavior and management of this rare malignancy and make it more familiar in clinical practice.

Role of ACTH in the Interactive/Paracrine Regulation of Adrenal Steroid Secretion in Physiological and Pathophysiological Conditions

In the normal human adrenal gland, steroid secretion is regulated by a complex network of autocrine/paracrine interactions involving bioactive signals released by endothelial cells, nerve terminals, chromaffin cells, immunocompetent cells, and adrenocortical cells themselves. ACTH can be locally produced by medullary chromaffin cells and is, therefore, a major mediator of the corticomedullary functional interplay. Plasma ACTH also triggers the release of angiogenic and vasoactive agents from adrenocortical cells and adrenal mast cells and, thus, indirectly regulates steroid production through modulation of the adrenal blood flow. Adrenocortical neoplasms associated with steroid hypersecretion exhibit molecular and cellular defects that tend to reinforce the influence of paracrine regulatory loops on corticosteroidogenesis. Especially, ACTH has been found to be abnormally synthesized in bilateral macronodular adrenal hyperplasia responsible for hypercortisolism. In these tissues, ACTH is detected in a subpopulation of adrenocortical cells that express gonadal markers. This observation suggests that ectopic production of ACTH may result from impaired embryogenesis leading to abnormal maturation of the adrenogonadal primordium. Globally, the current literature indicates that ACTH is a major player in the autocrine/paracrine processes occurring in the adrenal gland in both physiological and pathological conditions.

Autocrine/paracrine regulatory mechanisms in adrenocortical neoplasms responsible for primary adrenal hypercorticism

A wide variety of autocrine/paracrine bioactive signals are able to modulate corticosteroid secretion in the human adrenal gland. These regulatory factors, released in the vicinity of adrenocortical cells by diverse cell types comprising chromaffin cells, nerve terminals, cells of the immune system, endothelial cells, and adipocytes, include neuropeptides, biogenic amines, and cytokines. A growing body of evidence now suggests that paracrine mechanisms may also play an important role in the physiopathology of adrenocortical hyperplasias and tumors responsible for primary adrenal steroid excess. These intra-adrenal regulatory systems, although globally involving the same actors as those observed in the normal gland, display alterations at different levels, which reinforce the capacity of paracrine factors to stimulate the activity of adrenocortical cells. The main modifications in the adrenal local control systems reported by now include hyperplasia of cells producing the paracrine factors and abnormal expression of the latter and their receptors. Because steroid-secreting adrenal neoplasms are independent of the classical endocrine regulatory factors angiotensin II and ACTH, which are respectively suppressed by hyperaldosteronism and hypercortisolism, these lesions have long been considered as autonomous tissues. However, the presence of stimulatory substances within the neoplastic tissues suggests that steroid hypersecretion is driven by autocrine/paracrine loops that should be regarded as promising targets for pharmacological treatments of primary adrenal disorders. This new potential therapeutic approach may constitute an alternative to surgical removal of the lesions that is classically recommended in order to cure steroid excess.

Adrenal incidentaloma: A case of pheochromocytoma with sub-clinical Cushing's syndrome

Adrenal incidentalomas (AIs) are a cluster of different pathologies, but AIs with dual functional aspects are very rare. We report a case of AI with the evidence of both pheochromocytoma and sub-clinical Cushing's syndrome. A 42-year-old female patient presented with the history of abdominal pain. Abdominal computed tomography revealed right adrenal mass suggestive of pheochromocytoma. On endocrine evaluation, she admitted history of intermittent headache and palpitations for 4 years and was on treatment for hypertension and diabetes. There were no signs and symptoms suggestive of Cushing's syndrome. The laboratory data demonstrated 10 times raised 24-h urinary fractionated metanephrines with non-suppressible serum cortisol after 2-day low-dose dexamethasone suppression test. She underwent right-sided adrenalectomy with subsequent resolution of both pheochromocytoma and hypercortisolism. Patient was discharged in good clinical condition.

Ultrastructural findings in adrenal cortical adenomas clinically mimicking pheochromocytoma: a comparison with other adrenal tumors and tissue preparation techniques

Adrenal cortical tumors clinically mimicking pheochromocytomas are extremely rare, with 14 cases in the literature. The authors describe 2 patients with adrenal cortical adenoma (ACA) and catecholamine elevations. The impact of tissue preparation methods on electron microscopy (EM) images was assessed in ACA mimicking pheochromocytoma, pheochromocytoma, and ACA lacking pheochromocytoma-like symptoms. Ten adrenal cortical tumors were examined using EM after a variety of tissue preparation techniques, including fixation with glutaraldehyde, formalin for varying lengths of time followed by glutaraldehyde, and/or formalin followed by paraffin embedding. Electron micrographs were assessed for image quality and the presence of dense secretory granules and eccentric, norepinephrine (NE)-type granules. Images created from tissue fixed in glutaraldehyde and/or formalin and embedded in resin were of good quality, while those derived from paraffin-embedded specimens were poor with disrupted cellular architecture. When pheochromocytoma was fixed in glutaraldehyde for 24 h or in formalin for 8 days, eccentric granules were identified. These granules were absent when tissue was fixed in formalin for 20 days or was obtained from a paraffin block. ACA without pheochromocytoma-like symptoms and ACA mimicking pheochromocytoma both had noneccentric dense-core granules on EM regardless of tissue preparation, and eccentric NE-type granules were absent. ACA is a rare cause of pheochromocytoma-like symptoms. These tumors lack eccentric, NE-type dense-core granules present in pheochromocytoma. Glutaraldehyde alone or formalin fixation followed by glutaraldehyde produces electron micrographs that may aid in the diagnosis of adrenal cortical tumors, whereas formalin-fixed, paraffin-embedded tissue results in images that are inadequate.

Mixed corticomedullary adrenal carcinoma

Truly mixed corticomedullary tumors (MCMTs) are extremely rare and present as a single tumor mass composed of an intimately admixed population of both adrenal cortical cells and pheochromocytes. The current study describes the first case of a mixed corticomedullary adrenal carcinoma. In addition, we also review the published data on MCMTs to determine their clinical features, biochemical characteristics, pathological findings, and management. In order to compose this review, a search of the international literature for MCMTs was conducted. Fifteen related articles were found. The clinical and pathological information was obtained for all reported cases. MCMTs were found almost exclusively in females. In the vast majority of patients, the symptoms were related to the tumor's hormone hypersecretion. Hypertension and diabetes were present in 80 and 40 % of cases, respectively. Cushing's syndrome was reported in eight cases (53.33 %). A final diagnosis was made in all cases after surgery based on the pathological results. As of the writing of this article, all published cases of MCMTs had benign clinical behavior, with no instances of metastasis or death due to the tumor. MCMTs are currently considered to be benign tumors. Ours is the first case of malignant MCMT reported in the literature. The potential for malignancy should therefore be considered for these tumors.

Mixed corticomedullary carcinoma of the adrenal gland: a case report

OBJECTIVE

To report the case of a 78-year-old woman with mixed corticomedullary carcinoma of the adrenal gland, and to review other reported lesions that exhibit clinical and/or histopathologic features of both adrenal cortical and medullary differentiation.

METHODS

We describe the patient's clinical findings and laboratory test results, as well as the gross and histopathologic features of her tumor. We also review the literature pertaining to mixed corticomedullary adenomas and cortical tumors with clinical features of pheochromocytoma, and vice versa.

RESULTS

A 78-year-old woman with a 10-cm left adrenal mass was hospitalized for management of hypertensive urgency. Laboratory workup revealed elevated urinary metanephrine excretion and elevated serum dehydroepiandrosterone sulfate levels. She underwent left adrenalectomy. Pathologic examination of the lesion showed mixed cortical and medullary histologic characteristics, as well as gross and microscopic evidence of malignancy. Including the present case, we identified 17 cases of neoplasms that exhibit features of mixed corticomedullary differentiation.

CONCLUSIONS

This report represents the first documented case of mixed corticomedullary carcinoma. Several benign lesions combine clinical, biochemical, and/or histopathologic evidence of both adrenal cortical and medullary differentiation, including mixed corticomedullary adenomas and corticotropin-secreting pheochromocytomas. The differential diagnosis of a lesion with mixed cortical and medullary features should also include a malignant neoplasm.

Corticomedullary mixed tumor of the adrenal gland-a clinical and pathological chameleon: case report and review of literature

Adrenal tumors mostly present with specific and unique clinical features, regarding their endocrine metabolism. A 53-year-old man came to our Department for a left adrenal mass discovered incidentally. Biochemical and imaging findings were suspicious for a pheochromocytoma. The patient underwent a laparoscopic left adrenalectomy. A well-circumscribed 5.5-cm mass was removed. It was composed of adrenal cells intimately admixed with pheochromocytes. Immunohistochemical studies were positive both for cortical cells (inibin-α, synaptophysine and melan-A) and medullary cells (S-100 and chromogranine A). Final pathology was of corticomedullary mixed tumor (CMT). CMT is a rare tumor with 14 cases previously reported in literature, with wide variable biochemical behavior, such as his radiological and pathological features. Prevalence and actual malignant potential are yet unknown to our knowledge.

Corticomedullary mixed adrenal tumor: case report and literature review

We report a 66-year-old woman with a mixed corticomedullary tumor of the left adrenal gland. The patient was found to harbor an adrenal incidentaloma while investigated for a spigelian hernia. Due to the atypical radiological features and the relatively large size of the adrenal lesion she underwent a left adrenalectomy following endocrine testing to exclude a functional lesion. Subclinical Cushing's syndrome was suggested by the failure to obtain adequate cortisol suppression (less than 1.8 microg/dL) following dexamethasone administration pre-operatively; cortisol suppression was restored postoperatively following the excision of the tumor. Histology was consistent with a corticomedullary mixed adenoma, a lesion for which, there is paucity of published data regarding its natural history and long term outcome. The finding of this case highlights the importance of this extremely rare entity which should be included in the long list of causes of adrenal incidentaloma since cases with intra-operative complications have been described. The previously reported reappearance of this tumor in the contralateral adrenal gland emphasizes the need for prolonged follow-up.

Corticomedullary mixed tumor of the adrenal gland with concurrent adrenal myelolipoma

We report the case of a corticomedullary mixed tumor of the adrenal gland in a 55-year-old woman with a left adrenal mass who presented with mild symptoms of Cushing syndrome and an elevated urinary cortisol level. The patient underwent a left adrenalectomy. A well-circumscribed 2.5-cm mass, composed of an admixture of adrenal cortical cells and pheochromocytes, and an incidental 0.7-cm myelolipoma were present in the resected left adrenal gland. The diagnosis of adrenal corticomedullary mixed tumor was confirmed by both immunohistochemistry and electron microscopy. To our knowledge, this is the eighth well-documented report of this rare tumor.