Ectopic ACTH syndrome associated with anorectal carcinoma. Report of a case and review of the literature

ACTH-Secreting Neuroendocrine Carcinoma of the Cecum: Case Report and Review of the Literature

BACKGROUND

Approximately 30% of neuroendocrine tumors (NETs) present with secretory syndromes or develop one during the course of the disease. Cushing syndrome caused by a gastrointestinal tract NET is rare, with limited published information. We describe a patient with florid Cushing syndrome due to ectopic adrenocorticotropic hormone (ACTH) from a NET of colonic origin. A literature review was conducted to describe the spectrum of this clinical and pathologic entity as reported in the scientific literature.

PATIENT AND METHODS

Next-generation sequencing and microsatellite instability testing was carried out on the tumor from our case. A preliminary PubMed search was conducted using the following terms under the publication type "Case Reports": "Cushing" AND "colon," "neuroendocrine" AND "colon" and "neuroendocrine AND Cushing AND "colon." A manual search was performed to review all references for inclusion and relevant clinical, biochemical and pathologic data was abstracted.

RESULTS

Mutations in BRAF V600E and TP53 were detected in our case. We retrieved 18 previously reported cases of Cushing syndrome associated with a NET of colonic origin, none of which had next-generation sequencing performed. Median age at diagnosis was 54.5 years (range, 24-74 years), with equal gender distribution. ACTH was detected by immunohistochemistry in the primary tumor and/or metastatic lesion in 61.5%. Review of the reports suggested that ectopic ACTH secretion from a colonic tumor might be more common in mixed glandular and NETs, including mixed adenocarcinoma-neuroendocrine carcinoma. Among studies reporting outcomes, the unadjusted mortality rate was 77.7%, with median overall survival from presentation of 63 days (range, 17-380 days).

CONCLUSION

Cushing syndrome associated with ectopic ACTH from tumors of colonic origin is a rare phenomenon with poor outcomes and can be associated with pure NETs, adenocarcinomas, and mixed-phenotype tumors, including mixed adenocarcinoma-neuroendocrine carcinoma.

Small cell carcinoma of the rectum: A report of imaging results from four cases

Small cell carcinoma of the rectum is extremely rare. The present study aimed to improve the recognition of computed tomography (CT) and magnetic resonance imaging (MRI) features observed in patients with small cell carcinoma of the rectum. A total of 4 cases of patients with histologically confirmed small cell carcinoma of the rectum were retrospectively reviewed. The imaging features assessed consisted of the thickening of the rectal wall, local tumor invasion, CT density, MRI signal intensity, lesion texture, contrast enhancement characteristics, lymphadenopathy and distant metastasis. All 4 patients displayed ring-like rectal wall thickening and hypodensity in comparison to the gluteus muscles on non-enhanced CT images. MRI demonstrated isointensity on T1-weighted images and hyperintensity on T2-weighted images. Thickening of the left wall of the rectum with patchy low attenuation and the presence of an exophytic mass was observed in 1 patient. Local tumor invasion was observed in the perirectal fat spaces of 4 patients, in the prostate gland and seminal vesicle of 1 patient, and in the left seminal vesicle of 1 patient. Heterogeneous attenuation was exhibited on non-enhanced CT images in 3 lesions, and 1 lesion exhibited heterogeneous intensity on non-enhanced MRI images. All the lesions observed demonstrated strong enhancement following contrast imaging. Lymphadenopathy was observed in 4 patients, liver metastasis in 3 patients, pulmonary metastasis in 2 patients and multiple bone metastases in 1 patient. Overall, small cell carcinoma of the rectum appeared to be more likely to metastasize to the liver, pulmonary, lymph nodes and bone. Distinguishing features of small cell carcinoma of the rectum were noted as a thickening rectal wall, the presence of soft-tissue tumors, local tumor invasion, lymphadenopathy and distant metastases. Pre-operative CT and MRI are required as an aid in selecting the correct treatment plan and for the prognosis assessment of patients.

Mixed Adenoneuroendocrine Carcinomas (MANECs) of the Gastrointestinal Tract: An Update

The systematic application of immunohistochemical techniques to the study of tumors has led to the recognition that neuroendocrine cells occur rather frequently in exocrine neoplasms of the gut. It is now well known that there is a wide spectrum of combinations of exocrine and neuroendocrine components, ranging from adenomas or carcinomas with interspersed neuroendocrine cells at one extreme to classical neuroendocrine tumors with a focal exocrine component at the other. In addition, both exocrine and neuroendocrine components can have different morphological features ranging, for the former, from adenomas to adenocarcinomas with different degrees of differentiation and, for the latter, from well differentiated to poorly differentiated neuroendocrine tumors. However, although this range of combinations of neuroendocrine and exocrine components is frequently observed in routine practice, mixed exocrine-neuroendocrine carcinomas, now renamed as mixed adenoneuroendocrine carcinomas (MANECs), are rare; these are, by definition, neoplasms in which each component represents at least 30% of the lesion. Gastrointestinal MANECs can be stratified in different prognostic categories according to the grade of malignancy of each component. The present paper is an overview of the main clinicopathological, morphological, immunohistochemical and molecular features of this specific rare tumor type.

Imaging in covert ectopic ACTH secretion: a CT pictorial review

The syndrome of ectopic adrenocorticotrophin secretion (EAS) is rare and is due to excess adrenocorticotrophin (ACTH) production from a nonpituitary tumour. These tumours can be covert, where the tumours are not readily apparent, and very small making them challenging to image. It is clinically and biochemically difficult to distinguish between covert EAS and Cushing's disease. The first-line investigation in locating the source of ACTH production is computed tomography (CT). The aim of this pictorial review is to illustrate the likely covert sites and related imaging findings. We review the CT appearances of tumours resulting in covert EAS and the associated literature. The most common tumours were bronchial carcinoid tumours, which appear as small, well-defined, round or ovoid pulmonary lesions. Rarer causes included thymic carcinoids, gastrointestinal carcinoids and pancreatic neuroendocrine tumours. Awareness of the imaging characteristics will aid identification of the source of ACTH production and allow potentially curative surgical resection.

Cushing's syndrome secondary to bronchopulmonary carcinoid tumor: report of two cases and literature review

Bronchopulmonary carcinoid tumors have been associated with a variety of endocrine disorders including Cushing's syndrome (CS), which is caused by ectopic adrenocorticotrophic hormone (ACTH) secretion. We report two cases of CS secondary to bronchopulmonary carcinoid tumors. The first patient, a 29-year-old woman, presented hypokalemia, high serum ACTH level and high free-urinary cortisol, raising suspicion of an ectopic ACTH syndrome. Chest computed tomography and Octreoscan showed a peripheral nodule in the left-superior lobe of the lung. After lobectomy, a typical bronchopulmonary carcinoid was diagnosed. The second patient, a 16-year-old boy, presented "moon face" and progressive asthenia, high serum ACTH level and high free-urinary cortisol, raising the same hypothesis. Chest computed tomography and Octreoscan showed a peripheral nodule in the middle lobe. After lobectomy, an atypical bronchopulmonary carcinoid was diagnosed. Both cases had IA stage (T1N0M0), positively immunostaining for chromogranin and ACTH. Neither of these patients had hypophysary microadenomas, adrenal adenomas or recurrence of CS after surgical treatment, demonstrating that CS was caused solely by the presence of the bronchopulmonary carcinoid tumors.

Small cell carcinoma of rectum: A case report

We present a case of a 40-year-old woman with small-cell carcinoma (SCC) of the rectum. She had profuse bleeding in rectum for 5 d. By colonoscopy, polyps were determined in the rectum and biopsies were carried out. Histopathologically, the polyps were adenomatous. Because of the profuse bleeding in rectum, she underwent low anterior resection. After the diagnosis of SCC, she received intravenous chemotherapy with standard doses of siklofosfamid, adriamycin, and vepesid. Nevertheless, intracranial metastases were revealed and she died 6 mo after the operation.

An ectopic adrenocorticotropic hormone syndrome caused by a sacrococcygeal chordoma: report of a case with a slow progression

OBJECTIVE

To report the first case of an ectopic adrenocorticotropic hormone (ACTH) syndrome caused by a sacrococcygeal chordoma.

METHODS

We present a case report with clinical, laboratory, and histologic details.

RESULTS

A 76-year-old man was admitted to the hospital because of urinary obstruction. Five years previously, a urethral mass had been detected, and transurethral prostatectomy had been performed. Annual computed tomographic (CT) scans showed no change in size of the mass. In 1995, skin hyperpigmentation, central obesity, and bilateral edema were noted. The patient was admitted to the hospital in July 1996. A CT scan of the abdomen revealed a large mass close to the sacrum and compressing the bladder and rectum. Cortisol measurements (AM and PM) were 309 and 271 ng/mL, respectively. The plasma ACTH concentration was extremely elevated (3,125 pg/mL). Although resection of the mass was attempted, complete resection was not possible because the tumor had infiltrated the sacrum. Plasma cortisol concentrations in samples obtained 7 and 8 days postoperatively were normal. Plasma ACTH was substantially decreased (180 pg/mL) but remained above normal. The histologic features of the tumor were compatible with a chordoma. Neoplastic cells stained positively for ACTH.

CONCLUSION

This report describes the first case of an ectopic ACTH syndrome caused by a sacrococcygeal chordoma. A slow progression of symptoms in an ectopic ACTH syndrome had been described only for carcinoid tumors. These data add a new entry to the list of neoplasms capable of causing this syndrome.

[Anorectal neuroendocrine carcinoma and small cell carcinoma. Report of two cases]

INTRODUCTION

Anorectal neuroendocrine small cell carcinomas are rare and frequently difficult to treat.

EXEGESIS

Two women presented with a fungating tumor located on the upper part of the anal canal. Histology displayed neuron-specific enolase and chromogranin A immunoreactive small cell tumors. A plasmatic neuron-specific enolase secretion was noticed in one case. Tumors were poorly reactive to chemotherapy and irradiation, less than in usual epidermoid anal canal cancer. Evolution was quickly leading to hepatic and pulmonary metastases in both cases.

CONCLUSION

Anorectal neuroendocrine small cell carcinomas are rare but need to be individualized from epidermoid anal canal tumors owing to their poor prognosis with a frequent occurrence of hepatic and pulmonary metastasis.

Cushing syndrome due to ectopic adrenocorticotropic hormone secretion

Cushing syndrome (CS) caused by ectopic adrenocorticotropic hormone (ACTH) production (EA) poses major challenges diagnostically by mimicking the pituitary-dependent form of CS and therapeutically by producing severe, life-threatening hypercortisolemia. This retrospective follow-up study describes the clinical characteristics and course of EA in a large referral center. Computer-based cross-index codes for EA, CS, and bilateral adrenalectomy were used to identify patients treated at the Mayo Clinic between 1956 and 1998. EA was confirmed in 106 patients. Gender distribution showed a slight female predominance (61:45). Bronchial carcinoid was the most frequent cause of EA (25%), followed by islet cell cancer (16%), small-cell lung carcinoma (11%), medullary thyroid cancer (8%), disseminated neuroendocrine tumor of unknown primary source (7%), thymic carcinoid (5%), pheochromocytoma (3%), disseminated gastrointestinal carcinoid (1%), and other tumors (8%). No tumor was found in 16% of patients. Altogether, 28 patients were managed medically, and the others underwent curative tumor resection (13 patients) or bilateral adrenalectomy (65 patients). Surgically treated patients had longer survival, but this was most likely affected by treatment bias. The diagnoses of CS and ACTH-secreting neoplasm were usually concurrent, although, there were remarkable cases in which the two conditions were diagnosed several years apart. Curative resection of the tumor producing EA was possible in a small proportion of patients (12%). When curative resection is not possible, patients who are reasonable surgical candidates are likely to benefit from adrenalectomy. Additional experience with bilateral laparoscopic adrenalectomy should increase the number of patients who benefit from adrenal-directed surgery.

Small-cell carcinoma of the rectum: report of two cases

Small-cell carcinoma of the rectum is an infrequent pathologic finding, and its precise incidence is unknown. Its incidence is less than 0.2 percent among all colorectal cancers. This tumor manifests highly aggressive behavior. The treatment of choice is combination chemotherapy similar to that used for small-cell carcinoma of the lung, but in small localized tumors surgery plus chemotherapy is an alternative. We present two cases of small-cell carcinoma of the lower rectum and a review of the literature.

Small cell carcinoma of the vagina causing Cushing's syndrome by ectopic production and secretion of ACTH: a case report

BACKGROUND

Small cell carcinomas of pulmonary or extrapulmonary origin are neuroendocrine tumors classically associated with ectopic hormone production, particularly ACTH secretion resulting in Cushing's syndrome. However, ectopic Cushing's syndrome has not previously been reported in the setting of small cell carcinoma of the vagina.

METHODS

A primary vaginal tumor with hepatic metastases was evaluated with light microscopy. Serum cortisol and plasma ACTH levels were evaluated by radioimmunoassay and immunoradiometric assay, respectively, during a standard high-dose (8 mg) overnight dexamethasone suppression test.

RESULTS

Vaginal small cell carcinoma with hepatic metastases was demonstrated. Electrolyte abnormalities, elevated cortisol and ACTH levels, and failure to suppress ACTH secretion during high-dose dexamethasone administration confirmed the diagnosis of ectopic ACTH syndrome.

CONCLUSIONS

This case report establishes a clinical association between vaginal small cell carcinoma and ectopic Cushing's syndrome, confirming the neuroendocrine potential of this malignancy and features common to small cell neoplasms originating in other sites.

Colonic adenocarcinoma associated ectopic ACTH secretion: a case history

A 57-year-old woman developed features of Cushing's syndrome after resection of a Duke's C adenocarcinoma of the sigmoid colon. Biochemical and endocrine investigation indicated ectopic production of adrenocorticotrophic hormone (ACTH) as the cause for her condition. Hepatic metastases were detected by computed tomography (CT) scan. Histology of the original tumour displayed neuroendocrine characteristics but no definite evidence of ACTH synthesis. Treatment was instituted to control her hypercortisolism, and chemotherapy initiated to reduce the production of ectopic hormone. A clinical, biochemical and radiological response was obtained with complete resolution of her Cushing's syndrome. The tumour relapsed after several months with distant metastases, but no further endocrine abnormality was noted. A review of ectopic ACTH producing adenocarcinoma is given along with a discussion of the major pathological and therapeutic features of the case.