Primary esophageal melanoma is a rare disease with a poor prognosis. To date, 18 cases have been reported in Korea. Four patients visited the Chonnam National University Hwasun Hospital with dysphagia, followed by epigastric pain and discomfort, odynophagia, and weight loss. Esophagogastroduodenoscopy revealed a black pigmented polypoid mass, protruding mass, or black-pigmented flat lesions. Two patients had distant metastases and lymphadenopathies in imaging studies. Two patients underwent esophagectomy and intrathoracic esophagogastrostomy. One patient was treated with chemotherapy and interferon-alpha. The other patient declined further treatment. The routine histology using H&E revealed brown-colored atypical melanocytes. Immunohistochemical staining exhibited strong reactivity for Melan-A, S-100, and HMB-45 proteins. The biopsy specimens were interpreted to be malignant melanoma.One patient had multiple distant metastases 13 months after surgery. The other patient had no recurrence for 33 months after surgery. The patient treated with chemotherapy and interferon-alpha showed disease progression in the follow-up examination. Primary esophageal melanoma in Korea is a rare disease characterized by aggressive behavior, early metastasis, and poor prognosis.

We have experienced two patients who had hypokalemic metabolic alkalosis as well as hypomagnesemia and hypocalciuria with elevated plasma renin activity. We have performed renal clearance study after water loading, administration of furosemide and thiazide in two patients and two normal controls. Maximal free water clearance per 100 mL glomerular filtration rate(CH2O) and distal fractional chloride reabsorption[CH2O/(CH2O+CCl)] in our patients were reduced than the controls. Chloride clearance(CCl) was increased after furosemide administration but not after thiazide administration. Distal fractional chloride reabsorption[CH2O/(CH2O+CCl)] was dramatically decreased by furosemide administration in our patients, whereas thiazide had little effect on it. Fractional excretion of sodium, chloride, magnesium, calcium was increased by furosemide administration, whereas thiazide administration had little effect on this parameters. These findings suggested the presence of a defect in the distal convoluted tubule rather than in the thick ascending loop of Henle. Herein, we report two cases of Gitelman's syndrome diagnosed by renal clearace study after water loading, administration of furosemide and thiazide.
Alkalosis ; Calcium ; Filtration ; Furosemide ; Gitelman Syndrome* ; Humans ; Loop of Henle ; Magnesium Chloride ; Plasma ; Renin ; Sodium ; Water