Stage IV lung adenocarcinoma: partial responses to cisplatin-docetaxel and erlotinib, complicated by fistula

What happened, in summary

A 66-year-old woman was diagnosed in January 2008 with metastatic non-small cell lung adenocarcinoma, staged cT4N0M1. PET-CT showed metastases from the left lung to the contralateral lung and pleura. She also had a long-standing sigmoid colon herniation through an abdominal wall defect from prior abdominal surgery, but she had declined repair for many years because it caused no symptoms. For lung cancer, she received first-line cisplatin and docetaxel every 3 weeks for 6 cycles from January to July 2008. CT after treatment showed a partial response. In October 2008, imaging showed regrowth of the primary left upper-lobe mass and increased malignant pleural effusion, so erlotinib was started as second-line therapy. CT scans during the 1st, 3rd, 5th, and 7th months of erlotinib showed persistent partial response. A fall led to an L5 compression fracture, but bone biopsy showed osteoporosis-related fracture rather than bone metastasis. After 9 months on erlotinib, she was admitted with pneumonia symptoms, and examination also revealed an enterocutaneous fistula with fecal leakage through the old abdominal wall defect. Erlotinib was withheld. After 14 days of antibiotics for pneumonia, she underwent sigmoid colon resection and primary anastomosis. Pathology showed fistula-related bowel changes and no metastatic tumor. She recovered fully and was alive on outpatient follow-up without lung-cancer progression. The bowel complication was clinically important because fecal leakage appeared while the lung cancer was still controlled. Surgical pathology confirmed the colon problem was a fistula at the old herniation site, not spread of lung cancer to the bowel. Her lung cancer remained the central diagnosis during this complication management.