A 14-month-old, intact female Maltese (case 1) and a 26-month-old, spayed female Dachshund (case 2) had persistent regurgitation over 1 year and 2 years, respectively. In both cases, there were not specific findings in blood examination. Diagnostic imaging and fluoroscopy revealed that gastroesophageal reflux (GER) occurred when the patients ate a barium meal without abdominal contraction. They were treated with proton-pump inhibitor (esomeprazole), sucralfate and prokinetics (cisapride) while in a standing position for an hour after every meal, according to the gastroesophageal disease (GERD) suggested treatment. The case 1 dog was discharged with improved clinical signs, and the case 2 dog also had been improved clinical signs; however, aspiration pneumonia occurred in case 2, which was thought to be a complication from GERD. After receiving treatment for aspiration pneumonia, the case 2 dog was discharged from the hospital. Since there was no further improvement in symptoms after discharge, the case 1 dog was euthanized by owner's request, and the case 2 is alive, having only mild clinical signs upon the writing of this paper.

An 11-year-old, intact female, Miniature Poodle presented with an abdominal mass. The abdominal mass was located around the right fifth mammary gland. The surgically removed mammary mass was subjected to histopathological examination. Based on the microscopic interpretation, a final diagnosis of an intermediate grade infiltrative mammary comedocarcinoma was established. Computed tomography for metastasis evaluation after surgical resection of the tumor showed enlarged right medial iliac and right inguinal lymph nodes, and a micronodule in the accessory lung lobe, suggesting metastasis of the mammary gland tumor. Doxorubicin, a chemotherapeutic drug, was administered six times at three week intervals. However, despite chemotherapy, the masses around the fourth and fifth mammary gland on the right side enlarged in size, and the treatment was discontinued at the request of the owner. The anticancer response to mammary comedocarcinoma is poor and the patient is in hospice management. This is the first attempt to treat a case of canine mammary comedocarcinoma in South Korea.