Rapidly progressive cases of ectopic adrenocorticotropic hormone syndrome

Gracia Lucia Gonzalez; Gallardo Gema Lopez; Ahmed Bothayna Oulad; Fuentes Elena Dios; Romero Luis Beltran; Alfonso Soto-Moreno

doi:10.1530/endoabs.81.P133

Introduction: Adrenocorticotropic hormone (ACTH)-dependent Cushing’s syndrome (CS) secondary to an ectopic source is an uncommon condition, accounting for 4-5% of all cases of CS and between 9-18% of cases of ACTH-dependent CS. Although numerous malignancies have been associated with ectopic ACTH syndrome (EAS), lung neuroendocrine tumours (NETs) are the most common. Refractory hypokalemia can be the presenting feature in EAS and is seen in up to 80% of cases. We present two cases which first presented with hypokalemia, refractory to treatment with potassium supplementation and spironolactone.

Cases reports

Table 1
Gender:	Male	Female
Age: (years)	62	56
Clinical presentation	- Hypertension- Newly diagnosed hyperglycaemia- Hyperpigmentation- Peripheral edema	- Constitutional syndrome- Newly diagnosed hypertension and hyperglycaemia- Proximal myopathy- Peripheral edema
Biochemical parameters	Glucose 187 mg/dl	Glucose 150 mg/dl
	K⁺ 2.5 mEq/l (3.5 – 5)	K⁺ 2.2 mEq/l (3.5 – 5)
		pH 7.56; HCO3^- 49.1 mEq/l
Hormone parameters	UFC 14219.7 mg/24 h (35 – 135)	UFC 1268 mg/24 h (35 – 135)
	ACTH > 1500 pg/ml (3.6 – 60.5)	ACTH 276.9 pg/ml (3.6 – 60.5)
Tumor localization	Ileum	Lung
Tumour size	32 mm	17 mm
Histopathology:	Large-cell neuroendocrine carcinoma	Small-cell neuroendocrine carcinoma
Immunohistochemistry:	Chromogranin and synaptophysin positive. ACTH negative	Chromogranin, synaptophysin, CD56 and TTF1 positive. ACTH negative
Ki-67	70-80%	90%
Metastasis:	+	+
Treatment of hypercortisolism	Ketoconazole + somatostatin analogs	Ketoconazole
Outcome	Deceased	Deceased
Survival from time of diagnosis	19 days	12 days
UFC: 24 h-urinary free cortisol; Chromogranin, synaptophysin and CD 56: markers of neuroendocrine differentiation. TTF-1: primary site marker (lung and thyroid)

Conclusions: We present two cases of ectopic ACTH syndrome similar in their clinical presentation (newly diagnosed hyperglycaemia and hypertension and severe hypokalemia), tumour aggressiveness and rapidly fatal outcome. Furthermore, we present a case of EAS produced by a NET from the ileum tract. To our knowledge this is extremely rare and only described in isolated case reports

Endocrine Abstracts

P133