Ectopic ACTH secretion (EAS) associated to a well-differentiated peritoneal mesothelioma: case report

Our plain-English summary of Ectopic ACTH secretion (EAS) associated to a well-differentiated peritoneal mesothelioma: case report, by C.F. Mendoza, P. Ontiveros, D.X. Xibillé, et al (BMC Endocrine Disorders, 2015).

The study

• Authors: C.F. Mendoza, P. Ontiveros, D.X. Xibillé, H.M. Rivera
• Journal: BMC Endocrine Disorders
• Published: 2015;15:40
• Type of article: Case report
• Cited by: 7 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Background: The association between mesotheliomas and ectopic ACTH secretion has been rarely reported; we present the first case of ectopic ACTH secretion (EAS) associated with a well-differentiated peritoneal mesothelioma in whom the high dose dexamethasone suppression test (HDDST) results and plasmatic ACTH levels were similar to those found in Cushing's disease (CD).

Case Presentation: A 43-year-old hispanic woman with a 20 year history of treatment resistant diabetes mellitus and arterial hypertension. She had a full moon face, a buffalo hump, increased volume in both supraclavicular regions, purple striae in her arms and abdomen, truncal obesity, polymenorrhea and umbilical hernia. A cortisol suppression test with low dose dexamethasone (LDDST) with a result of 16.6 μg/dL and ACTH plasma levels were measured at 32.6 pg/mL. The high dose dexamethasone test suppression percentage was 84.8% and magnetic resonance imaging (MRI) showed no evidence of pituitary alterations, computed tomography (CT) showed images suggestive of uterine fibroid and an intra-abdominal tumor that correlated with an umbilical hernia, which reinforcement after contrast. Surgery was performed, finding uterine fibroids and paracolic tumor implants as well as on the omentum, bladder, bowel, ovaries and appendix. Pathology reported a well-differentiated peritoneal mesothelioma with positive immunohistochemistry for ACTH.

Conclusions: Although most cases of ectopic secretion of ACTH derive from rapidly-developing lung tumors, with very high plasma ACTH levels and cortisol suppression percentages with high doses of dexamethasone under 60%, there is a small percentage of slow-developing, chronic tumors that are biochemically undistinguishable from Cushing's disease. Following the expert recommendations regarding imaging techniques it is possible to identify the associated tumor in most cases.

In plain English

This case report described a 43-year-old Hispanic woman, seen at a hospital in Cuernavaca, Mexico. She had a 20-year history of treatment-resistant diabetes and high blood pressure, and signs of Cushing's syndrome (too much cortisol). Her blood ACTH level was 32.6 pg/mL, which the authors noted was at the lower limit of normal. A high-dose dexamethasone test lowered her cortisol by 84.8%, a result similar to Cushing's disease, which starts in the pituitary gland. Pituitary MRI was normal. A CT scan showed a 68x60x76 mm abdominal tumor pushing through the navel. At surgery, tumor deposits were found on the omentum, bladder, bowel, ovaries and appendix, and not all could be removed. Pathology found a well-differentiated papillary peritoneal mesothelioma that stained positive for ACTH. Her cortisol stayed high after surgery, and she was treated with ketoconazole. The article did not describe any asbestos exposure. The authors concluded that a small percentage of slow-growing ACTH-producing tumors cannot be told apart from Cushing's disease by blood tests.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case report (a single patient)
• Who was studied: One 43-year-old Hispanic woman treated at the authors' center (Hospital General de Cuernavaca, Morelos, Mexico), with a 20-year history of diabetes, hypertension and signs of Cushing's syndrome
• Exposure: The article reports no asbestos, occupational or environmental exposure for this patient. Its background section, citing other sources, states that well-differentiated papillary and benign multicystic peritoneal mesotheliomas are not related to asbestos.
• Main results:
  • In this patient, serum cortisol after the low-dose (1 mg) dexamethasone test was 16.6 μg/dL and plasma ACTH was 32.6 pg/mL
  • Cortisol suppression on the high-dose dexamethasone test was 84.8%, and pituitary MRI at two different centers was normal
  • Abdominal CT showed an intra-abdominal tumor protruding through the umbilicus, measuring 68x60x76 mm; a mesothelioma was considered possible
  • At surgery there were abundant ascites and tumor implants in the omentum, bladder, bowel, ovaries and appendix. An intraoperative biopsy first reported ovarian carcinoma, and the implants could not be completely removed.
  • Final pathology found a well-differentiated papillary mesothelioma with diffuse positive staining for ACTH, plus calretinin and thrombomodulin staining supporting mesothelioma
  • After surgery, cortisol remained high. AM serum cortisol was 20.9 μg/dL at 24 hours. One month later, urinary free cortisol was 143.6 μg/day and post-1 mg dexamethasone cortisol was 19.1 μg/dL.
  • The patient was not cured. She was treated with ketoconazole 400 mg once a day and did not want further treatment or invasive procedures.
  • The authors noted that this patient's plasma ACTH was at the lower limit of the normal range
• The authors' conclusion: The authors concluded that most ectopic ACTH cases come from fast-growing lung tumors, but that a small percentage of slow-developing, chronic tumors cannot be distinguished biochemically from Cushing's disease. They added that following expert imaging recommendations can identify the tumor in most cases.
• Limitations the authors state:
  • The authors could not review the results of the inferior petrosal sinus catheterization performed 13 years earlier at another center, and inferred its result from the patient's later care
  • Somatostatin receptor scintigraphy and PET/CT were not performed because they are difficult to access in most of the authors' country

Topics

The National Library of Medicine indexes this study under subjects our site covers: Mesothelioma, Peritoneal mesothelioma.

Medical terms in this study, explained in our Lexicon: Well-Differentiated, Peritoneal Mesothelioma, Mesothelioma, Umbilical Hernia, Omentum, Pathology, Immunohistochemistry.

Related studies

• Chromosome 3 and 12p rearranged in a well-differentiated peritoneal mesothelioma — H.J. Decker, F.P. Li, et al. (1990)
• Clinical Characteristics and Outcomes of Patients with Well-Differentiated Papillary Peritoneal Mesothelial Tumors — M. Offin, N. Aguirre, et al. (2024)
• Well-differentiated papillary mesothelioma: peritoneal implants are not always metastases in the presence of cancer — G.W. Irwin, A. Ervine, et al. (2014)
• Peritoneal well-differentiated papillary mesothelioma coexisting with endometrial adenocarcinoma mimicking peritoneal carcinomatosis: A case report — Y.Y. Chen, P.C. Li, et al. (2020)
• Peritoneal well-differentiated papillary mesothelioma associated with infertility in a 37-year-old woman — B. Pang, C. Hu, et al. (2021)
• Collagenous Spherulosis in Well-Differentiated Papillary Mesothelioma in a Female With Multilocular Peritoneal Inclusion Cysts — B. AbdullGaffar, L.G. Raman (2019)

Browse return to medical research.