Acinic cell adenocarcinoma of the parotid with ectopic production of adrenocorticotropic hormone

ACTH-secreting parotid acinic cell carcinoma unusually reported as a paraneoplastic syndrome

Paraneoplastic syndromes, induced by an immunological cross-reaction or hormone/peptide secretion, are an atypical presentation of tumors. Some tumors, such as small cell lung cancer and bronchial carcinoid, can be adrenocorticotropic hormone (ACTH) secreting tumors. Less commonly, parotid acinic cell carcinoma can be ACTH-secreting tumor leading to Cushing’s syndrome. Few literature cases have described ACTH related paraneoplastic syndrome of parotid adenocarcinoma. Because of the rarity of the condition, little is known about the management and prognosis of this phenomenon. In this report, we highlighted the case of a 59-year-old male with a past medical history of parotid adenocarcinoma treated with surgery, chemotherapy, and radiation therapy presented with clinical and biochemical signs of hyperaldosteronism. Abdominal ultra-sound, computed tomography, and magnetic resonance imaging showed hepatic mass. Liver biopsy with immunohistochemistry confirmed the presence of parotid adenocarcinoma secreting ACTH. He is on paclitaxel and carboplatin medication with good clinical response.

Ectopic ACTH Secretion Secondary to Metastatic Acinic Cell Carcinoma of the Parotid Gland: A Case Report and Review of Current Evidence for Systemic Therapy

Acinic cell carcinoma is a rare, typically indolent, neoplasm that arises in the salivary glands. Metastatic disease is uncommon, occurring in around 10% of cases. We report the case of a 46-year-old male in whom the first sign of disseminated disease was increased skin pigmentation due to paraneoplastic Cushing’s syndrome. He underwent 3 cycles of chemotherapy with carboplatin and paclitaxel with no symptomatic improvement and a mixed response on imaging. There is no evidence that systemic therapy prolongs survival in metastatic acinic cell carcinoma, and we lack a consensus as to which treatment options are most beneficial. A summary of published evidence regarding choice of palliative chemotherapy regimens and response is discussed in relation to the case.

Ectopic ACTH Production Caused by Metastatic Parotid Gland Acinic Cell Carcinoma

Objective

To present a case of adrenocorticotropic hormone (ACTH) hypersecretion caused by a metastatic acinic cell carcinoma (AcCC) of the parotid. Only 6 cases have been reported prior to October 2019. We believe that this condition is under-reported and hope that improved recognition will improve its reporting.

Methods

Diagnosis in this case was done using surgical pathology of the primary tumor, involving lymph nodes, and a metastatic lesion. Following an initial misdiagnosis, a final diagnosis of AcCC was made using immunohistochemical staining. ACTH hypersecretion was diagnosed by testing for random ACTH, cortisol, and 24-hour urine aldosterone and cortisol levels.

Results

A 57-year-old man presented with hypokalemia, lower-extremity edema, and left-side rib pain 7 months following excision of a 4-cm left-parotid tumor. Immunostaining positive for DOG-1, CK7, pan-cytokeratin (including CAM5.2), and SOX10 led to the diagnosis of AcCC. ACTH hypersecretion was diagnosed based on a random ACTH level of 307 pg/mL (normal morning value, 7.2-63 pg/mL), a cortisol level of 33 μg/dL (normal morning value, 4.3-19.8 μg/dL; normal PM value, 3.1-15.0 μg/dL), a 24-hour urine aldosterone level of <0.7 U (normal, 2.0-20 U), and a 24-hour urine cortisol level of 4564 U (normal, 3.5-45 U). The patient’s ACTH hypersecretion and hypokalemia were treated with potassium replacement, amiloride, and ketoconazole. His metastatic recurrence was treated with radiotherapy, chemotherapy, and immunotherapy. The patient died after being diagnosed with sepsis secondary to multifocal postobstructive pneumonia 4 months after the diagnosis of his metastatic recurrence.

Conclusion

Ectopic ACTH production caused by metastatic AcCC is a rare phenomenon but has been increasingly described over the last 15 years. We believe that this condition likely has a greater prevalence than what is reported and that improved recognition will lead to improved outcomes.

Ectopic Cushing's Syndrome Unveiling a Metastatic Parotid Carcinoma

Introduction

Adrenocorticotropic hormone (ACTH) ectopic production is a rare cause of Cushing syndrome (CS). The most commonly associated tumours are small-cell lung carcinoma along with bronchial and thymic carcinoids. To date, only 5 cases have been published in the literature featuring ectopic ACTH secretion from metastatic acinic cell carcinoma (ACC) of the parotid gland. We hereby describe a very uncommon case of ectopic CS (ECS) unveiling a metastatic parotid ACC.

Case Presentation

A 46-year-old man with hypertension and dyslipidemia diagnosed 4-months before, as well as new-onset diabetes mellitus unveiled 1-month earlier, was referred to emergency department for hypokalemia. Hormonal study and dynamic biochemical tests performed indicated ECS. Imaging and cytological findings pointed toward a likely primary right parotid malignancy with liver metastases. Somatostatin receptor scintigraphy has shown an increased uptake in the parotid gland and mild expression in liver metastasis. The patient underwent right parotidectomy, and histopathologic examination confirmed ACC. Meanwhile, hypercortisolism was managed with metyrapone, ketoconazole, and lanreotide. Despite chemotherapy onset, a rapid disease progression and clinical course deterioration was observed.

Conclusion

The present report highlights a rare ECS, exposing a metastatic parotid ACC, with an aggressive and challenging clinical course, representing the first case whose diagnosis of ECS came prior to ACC.

Ectopic ACTH Production and Cushing's Syndrome in a Patient with Parotid Acinic Cell Carcinoma with High-Grade Transformation: Tumor Context and Clinical Implications

We report a rare case of Cushing's syndrome in a 59-year-old man who initially presented with concurrent acinic cell carcinoma of the parotid with high-grade transformation and co-existing papillary and medullary thyroid carcinomas, without noticeable cushinoid symptoms. Six-months later, he developed clinical features of Cushing's syndrome which coincided with disease progression in the form of lung metastasis and mediastinal lymphadenopathy. Ectopic adrenocorticotropic hormone (ACTH) production and protein expression was limited to the high-grade transformed component of acinic cell carcinoma and in the lymph node metastasis, and was absent in the conventional acinic cell carcinoma as well as in the papillary and medullary thyroid carcinoma. He received adjuvant chemotherapy and supportive management with interval improvement for 8 months followed by disease progression with increasing serum cortisol levels and bone metastasis. He was offered palliative chemotherapy, however, declined further therapy and was lost to follow up. We discussed clinical and pathologic implications of ectopic ACTH production associated with acinic carcinoma and also reviewed the literature of this rare paraneoplastic syndrome.

Salivary acinic cell carcinoma: reappraisal and update

Epidemiologic and clinicopathologic features, therapeutic strategies, and prognosis for acinic cell carcinoma of the major and minor salivary glands are critically reviewed. We explore histopathologic, histochemical, electron microscopic and immunohistochemical aspects and discuss histologic grading, histogenesis, animal models, and genetic events. In the context of possible diagnostic difficulties, the relationship to mammary analog secretory carcinoma is probed and a classification is suggested. Areas of controversy or uncertainty, which may benefit from further investigations, are also highlighted.

Cushing's syndrome associated with bronchial adenoma

A case of Cushing's syndrome associated with a bronchial adenoma treated eight years before with bilateral adrenalectomy was cured by surgical excision of the bronchial adenoma. A discussion of clinical and hormonal features of this lesion is presented. It is concluded that this tumor manifested a capability of synthesizing and releasing substances which are chemically and biologically similar to adrenocorticotropic hormone andmelanocyte-stimulating hormone (MSH). Stimulation of the adrenal cortex by this material results in hyperplasia and hypersecretion, and stimulation of the melanocytesy MSH resulted in excessive pigmentation. Acknowledgment: We are indebted to Doctors Wendell Nicholson, David N. Orth, and Grant W. Liddle of Vanderbilt University for determinations of ACTH and MSH levels and to Mrs. E.P. Jessup for assistance in preparation of statistical data for this manuscript.

[Morphology of salivary gland diseases]

The human salivary glands represent a functional system with manifold responsibilities and interactions to the organism. The major and minor salivary glands show a common construction schedule consisting of an acinar functional system for the production of an enzyme- and mucin-containing primary saliva and a ductal functional system with manifold secretory, resorptive and regulatory responsibilities for the transport and the definitive composition of the saliva. The cyclic AMP and calcium iones localized in the glandular acini have an exceptional importance for the course of the secretory process. The neurohormonal control of the salivary secretion results by adrenergic and cholinergic transmitter substances. Moreover the secretory process shows a daily cycle combined with morphological alterations of the glandular cells (so called circadian structures). The fluid secretion of the salivary duct system (the output of sodium-, potassium- and chlorine-iones) represents an active energy-consumed transport process which will be regulated by several factors (autonomic nervous system, quantity of perfusion, hydrostatic pressure in the blood capillaries, transepithelial active transport by ATP-consumed pump systems). The striated ducts are the functional most important sector of the duct system for a rapid fluid- and electrolyte excretion. The terminal axons of the postganglionic sympathic and parasympathic neurits are characterized by spindle-shaped enlargements (varicosities) which contain neurosecretory granules. In the region of the acinar and intercalated duct cells a direct synaptic contact exists for the stimulation transmission, in the course of which the terminal axon contacts immediately with the effector cell by penetration of the basement membrane. The salivary glands form a part of the stabil tissues with reversible postmitotic cells in regard of the tissue regeneration. Under pathological conditions (inflammations, impediment of secretion fluid, radiation effects etc.) metaplasias and proliferations of the duct system arise with development of indifferent duct formations analogous to the type of an embryonal salivary gland. The terminal zone between intercalated and striated ducts represents an indifferent zone with large regeneratory potency. A special behaviour shows the myoepithelial cells which are developed as well to the outside of primitive embryonic duct buds as differentiated intercalated and striated ducts. Morphologically three types of diseases can be classified in the salivary glands: sialadenosis, sialadenitis and tumours.(ABSTRACT TRUNCATED AT 400 WORDS)