What happened, in summary

A 45-year-old woman first developed genital and leg swelling and was treated for what appeared to be idiopathic lymphedema. Several months later she developed rapidly recurring fluid around both lungs, requiring thoracentesis every few days. Initial pleural-fluid tests did not show cancer, and she had no gastric symptoms.

PET/CT showed enlarged lymph nodes in the chest and left axilla. Biopsy of an axillary node revealed signet-ring cell carcinoma. Endoscopy then found a small lesion in the stomach, and gastric biopsy showed the same cancer. Malignant chylous ascites and later malignant pleural fluid confirmed widespread disease. She was diagnosed with HER2-negative Stage IV gastric cancer.

Managing the pleural effusions was difficult. Bilateral drainage and repeated thoracentesis were needed before and during cancer treatment. She received four cycles of capecitabine plus oxaliplatin, but evaluation after the first two cycles showed progression. A right-sided pleurodesis eventually reduced fluid on that side, while the left pleural effusion remained uncontrolled.

Her overall condition worsened despite treatment. She died 6 months after the diagnosis of gastric carcinoma.