腫瘤引起的低血糖

Tumor-Induced Hypoglycemia

腫瘤引起的低血糖（tumor-indluced hypoglycernia， TIH）或非胰島細胞腫瘤性低血糖（non-islet cell tumore hypoglycernia， NICTH） 指胰島細胞腫瘤以外的其他腫瘤引發的低血糖症，也就是一種腫瘤相關症侯群 （paranleoplastic syndrome）。這些 NICTH主要發生於巨大的良性或惡性之腫瘤，大多數腫瘤大於十公分以 上。常見的病理組織為間質細胞（nesenchyimal）或上皮細胞（epithelial）腫瘤。1988年以前都認為 NICTH 是 腫瘤體積太大消耗過量澱粉而引起，之後才發現乃是腫瘤分泌巨大第二型類胰島素生長因子 （macronmolecule insulin-like growth factor-II， IGFII）所致。實驗室檢查當低血糖時，血中的第二型類胰島素 生長因子（IGF-II）之濃度會上升，其他胰島素、C-peptide 及第一型類胰島素生長因子（IGFI）及生長素荷爾 蒙之濃度都被抑制偏低。當 IGFII 濃度/IGFI 濃度之比大於10 時，表示臨床上非常有意義，可以作為診斷NICTH之依據。目前治療低血糖的方法最好就是將腫瘤完全切除，若無法完全切除最少也要將腫瘤體積 | 減少。內科治療可以注射人體生長素或給予大量的類固醇，來改善低血糖之現象。結論，腫瘤引起的低血糖主要是巨大的良性或惡性之腫瘤分泌第二型類胰島素生長因子（IGFII）所引起。目前治療的最好方法 「就是將腫瘤完全切除，若無法完全切除，可以給予大量類固醇或注射人體生長素。

Tumor-induced hypoglycemia (TIH) or non-islet cell tumor hypoglycemia (NICTH) is described as a tumor-induced hypoglycemia other than insulinoma which is also a manifestation of paraneoplastic syndrome. In most cases, NICTH occurs in subjects with a large solid tumor of mesenchymal or epithelial origins over 10 cm in diameter. Tumor could be either benign or malignant. By 1998, the pathophysiology of NICTH was believed due to over-consumption of glycogen by a huge tumor. Later on, it was confirmed that NICTH caused by overproduction of macro IGFII molecules. Typically, the elevated IGFII levels in NICTH are associated with suppressed the serum levels of insulin, C-peptide, IGFI, and growth hormone. An IGFII: IGFI ratio of >10 is considered to be clinically significant and highly suggestive of NICTH. A complete surgical resection or de-bulking of the tumor whenever possible is the treatment of choice and if successful, usually results in resolution of hypoglycemia. For the inoperable one, high dose glucocorticoid and human growth hormone therapy has been shown to resolve hypoglycemia. In conclusion, TIH or NICTH is caused by overproduction of macro IGFII molecules by a large tumor. A complete surgical resection of the tumor whenever possible is the treatment of choice. For the inoperable one, a high dose or glucocorticoid or human growth hormone therapy has been shown to resolve hypoglycemia.