Published online May 26, 2019. doi: 10.12998/wjcc.v7.i10.1213
Peer-review started: January 25, 2019
First decision: March 9, 2019
Revised: March 17, 2019
Accepted: March 26, 2019
Article in press: March 26, 2019
Published online: May 26, 2019
Processing time: 123 Days and 1.9 Hours
Small-cell lung cancer (SCLC) is a type of fatal tumor that is increasing in prevalence. While these are unpleasant facts to consider, it is vitally important to be informed, and it is important to catch the disease early. Typically, lung cancer does not show severe clinical symptoms in the early stage. Once lung cancer has progressed, patients might present with classical symptoms of respiratory system dysfunction. Thus, the prognosis of SCLC is closely related to the early diagnosis of the disease. Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is related to cancer occurrence, especially for SCLC with the presence of Cushing's syndrome, which is dependent on markedly elevated ACTH and cortisol levels.
In the current report, we describe two middle-age patients who were originally diagnosed with diabetes mellitus with no classical symptoms of lung cancer. The patients were eventually diagnosed with SCLC, which was confirmed by bronchoscopic biopsy and histopathology. SCLC-associated diabetes was related to EAS, which was an endogenous ACTH-dependent form of Cushing’s syndrome with elevated ACTH and cortisol levels. Multiple organ metastases were found in Patient 1, while Patient 2 retained good health at 2 years follow-up. EAS symptoms including thyroid dysfunction, hypercortisolism and glucose intolerance were all resolved after anticancer treatment.
In conclusion, SCLC might start with diabetes mellitus and increased cortisol and hypokalemia or other EAS symptoms. These complex clinical features were the most significant factors to deteriorate a patient’s condition. Early diagnosis and treatment from clinicians were essential for the anti-cancer treatment for patients with SCLC.
Core tip: Small-cell lung cancer (SCLC) is a fatal tumor that is increasing in prevalence. Prognosis of patients with SCLC is closely related to early diagnosis. We report two middle-aged patients who were originally diagnosed with diabetes mellitus with no classical symptoms of lung cancer. Ectopic adrenocorticotropic hormone syndrome symptoms including thyroid dysfunction, hypercortisolism, and glucose intolerance, which are related to elevated adrenocorticotropic hormone and cortisol levels, were all normal after anticancer treatment. Our findings highlight that SCLC might start with diabetes mellitus and increased cortisol level and hypokalemia or other ectopic adrenocorticotropic hormone syndrome symptoms, and it reminds clinicians of the importance of early diagnosis of SCLC with ectopic adrenocorticotropic hormone syndrome.