Supplementary Material for: Small Cell Lung Cancer with dual Paraneoplastic Syndromes: A Case Report

Background:
Paraneoplastic syndromes are common in cancers such as lung, breast, and ovarian cancers. Still, the dual paraneoplastic syndromes of Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) and raised pancreatic enzymes at the same time are rare. EAS is due to the production of ACTH by tumors other than the pituitary gland, which stimulates the hyperplasia of the adrenal cortex to secrete excessive corticosteroids, most commonly in lung cancer. Elevated pancreatic enzymes are associated with ectopic secretion from lung cancer. Clinically, some patients with Small cell lung cancer (SCLC) have atypical early clinical manifestations and may present with paraneoplastic syndrome as the first symptom.
Case report:
This article describes a case of a 45-year-old male patient who was admitted to the hospital with “intermittent mild edema of both lower extremities for more than 1 month”, and showed persistent low potassium without diuretic drugs, and with abnormally high blood amylase and blood lipase in the exclusion of pancreatitis. The persistent low potassium was caused by unusually high cortisol levels in patients with EAS. that result from large amounts of cortisol secretion. Pancreatitis was excluded, and he was finally diagnosed with extensive-stage SCLC after bronchoscopic biopsy and histopathological confirmation. The patient presented with dual paraneoplastic syndromes of SCLC combined with EAS, high pancreatic enzymes, dual metastases, high malignancy, loss of surgical opportunities, and poor prognosis. The patient died at the end of the first cycle of chemotherapy due to the combination of IV degree of myelosuppression, metabolic alkalosis, severe infection, and respiratory failure. , and died due to the rapid deterioration of his condition.
Conclusion:
Most of the clinical manifestations of lung cancer with paraneoplastic syndrome as the first symptom lack specificity. The paraneoplastic syndrome of lung cancer can appear in all stages of the disease, and if it appears before the diagnosis of lung cancer, it is of some significance in guiding the diagnosis of lung cancer. Meanwhile, when pancreatic lesions are excluded, we should consider malignancy-related hyperpancreatinemia.

背景：在肺癌、乳腺癌和卵巢癌等癌症中，副肿瘤综合征较为常见。然而，同时出现的异位促肾上腺皮质激素（ACTH）综合征（EAS）和胰腺酶升高这一双重副肿瘤综合征却较为罕见。EAS是由于除垂体以外的肿瘤产生ACTH，刺激肾上腺皮质增生并分泌过量的皮质类固醇，最常见于肺癌。胰腺酶升高与肺癌的异位分泌相关。临床上，一些小细胞肺癌（SCLC）患者表现出典型的早期临床表现，可能以副肿瘤综合征作为首发症状。案例报告：本文描述了一位45岁男性患者，因“双下肢间歇性轻度水肿超过1个月”入院，并表现出无利尿药物的低钾血症，以及排除胰腺炎后异常高的血淀粉酶和血脂肪酶。EAS患者中持续的低钾血症是由于皮质醇水平异常升高，这导致大量皮质醇分泌。排除胰腺炎后，经支气管镜活检和病理学证实，最终诊断为广泛期SCLC。患者表现出SCLC与EAS、高胰腺酶、双重转移、高恶性度、失去手术机会和预后不良的双重副肿瘤综合征。患者在化疗第一周期结束时因骨髓抑制IV度、代谢性碱中毒、严重感染和呼吸衰竭而死亡，终因病情迅速恶化而去世。结论：以副肿瘤综合征作为首发症状的肺癌的临床表现大多缺乏特异性。肺癌的副肿瘤综合征可出现在疾病的任何阶段，若在肺癌诊断之前出现，对肺癌的诊断具有一定的指导意义。同时，在排除胰腺病变后，应考虑与恶性肿瘤相关的胰腺酶高血症。