内容紹介
A Case of Central Diabetes Insipidus That Was Caused by Pituitary Metastasis of Lung Adenocarcinoma and Was Controlled by Radiation Therapy
Summary
Background: Pituitary metastasis of lung cancer is rare; however, it often causes diabetes insipidus. Although the majority of such patients are treated with radiation therapy, it remains unclear whether diabetes insipidus can be controlled by radiation therapy. Case: A 72-year-old man was admitted to our hospital for hemosputum, headache, and polyuria. A chest CT scan showed a 3.0 cm mass in the left upper lobe of his lung. Bronchofiberscopy results confirmed the pathological diagnosis of lung adenocarcinoma. Based on the findings from PET-CT, head MRI, and endocrine tests, the diagnosis of lung adenocarcinoma(cT1bN0M1b, stageⅣ)accompanied with central diabetes insipidus caused by pituitary metastasis was made. Oral administration of desmopressin reduced urine volumes; however, chemotherapy for achieving stable disease in the primary tumor was ineffective in controlling the symptoms of diabetes insipidus. Chemotherapy was discontinued after 4 months because of severe hematological toxicity. During 2 months after the cessation of chemotherapy, polyuria worsened and, therefore, radiation therapy for pituitary metastasis was started. Following the radiation therapy, an apparent reduction in urine volume was observed. Conclusion: Our experience of this case suggests that radiation therapy for pituitary metastasis should be considered at the time when diabetes insipidus becomes clinically overt.
要旨
背景: 肺癌の下垂体転移はまれであるが,時に尿崩症の発症原因になることが知られている。下垂体転移に対しては放射線治療が施行されることが多いが,下垂体転移によって発症した尿崩症への効果は不明である。症例: 72歳,男性。血痰と頭痛,多尿を主訴に受診し,胸部CT検査で左肺上葉に30 mm大の腫瘤影が認められ,気管支鏡検査により肺腺癌と診断された。PET-CTと頭部MRI,内分泌負荷試験の結果から,下垂体転移による中枢性尿崩症を合併した肺腺癌cT1bN0M1b,stageⅣと診断された。尿崩症による多尿はデスモプレシン経口薬により改善を認めたが,原発巣はstable diseaseと評価できた化学療法自体は尿崩症の症状改善には無効であった。骨髄抑制のために化学療法は4か月間の実施で中止されたが,その2か月後に下垂体転移の増悪によると思われる尿崩症症状の悪化が認められた。化学療法が無効であったことから,同部位に対して放射線治療が施行され,尿崩症の改善を認めた。結論: 本症例の経験は,中枢性尿崩症を呈する下垂体転移症例への早期の局所放射線治療導入を支持するものである。
目次
Summary
Background: Pituitary metastasis of lung cancer is rare; however, it often causes diabetes insipidus. Although the majority of such patients are treated with radiation therapy, it remains unclear whether diabetes insipidus can be controlled by radiation therapy. Case: A 72-year-old man was admitted to our hospital for hemosputum, headache, and polyuria. A chest CT scan showed a 3.0 cm mass in the left upper lobe of his lung. Bronchofiberscopy results confirmed the pathological diagnosis of lung adenocarcinoma. Based on the findings from PET-CT, head MRI, and endocrine tests, the diagnosis of lung adenocarcinoma(cT1bN0M1b, stageⅣ)accompanied with central diabetes insipidus caused by pituitary metastasis was made. Oral administration of desmopressin reduced urine volumes; however, chemotherapy for achieving stable disease in the primary tumor was ineffective in controlling the symptoms of diabetes insipidus. Chemotherapy was discontinued after 4 months because of severe hematological toxicity. During 2 months after the cessation of chemotherapy, polyuria worsened and, therefore, radiation therapy for pituitary metastasis was started. Following the radiation therapy, an apparent reduction in urine volume was observed. Conclusion: Our experience of this case suggests that radiation therapy for pituitary metastasis should be considered at the time when diabetes insipidus becomes clinically overt.
要旨
背景: 肺癌の下垂体転移はまれであるが,時に尿崩症の発症原因になることが知られている。下垂体転移に対しては放射線治療が施行されることが多いが,下垂体転移によって発症した尿崩症への効果は不明である。症例: 72歳,男性。血痰と頭痛,多尿を主訴に受診し,胸部CT検査で左肺上葉に30 mm大の腫瘤影が認められ,気管支鏡検査により肺腺癌と診断された。PET-CTと頭部MRI,内分泌負荷試験の結果から,下垂体転移による中枢性尿崩症を合併した肺腺癌cT1bN0M1b,stageⅣと診断された。尿崩症による多尿はデスモプレシン経口薬により改善を認めたが,原発巣はstable diseaseと評価できた化学療法自体は尿崩症の症状改善には無効であった。骨髄抑制のために化学療法は4か月間の実施で中止されたが,その2か月後に下垂体転移の増悪によると思われる尿崩症症状の悪化が認められた。化学療法が無効であったことから,同部位に対して放射線治療が施行され,尿崩症の改善を認めた。結論: 本症例の経験は,中枢性尿崩症を呈する下垂体転移症例への早期の局所放射線治療導入を支持するものである。