Increased adverse events associated with chemotherapy and radiotherapy in patients with second primary esophageal cancer after hematologic malignancy

Background: Patients treated for hematologic malignancy are at increased risk of developing subsequent malignant neoplasm (SMN) and may experience severe adverse events during chemotherapy or radiotherapy for these tumors because of cumulative damage to multiple organ systems. This study evaluated the incidence of treatment-related adverse events (TRAEs) during and after chemotherapy or radiotherapy for subsequent malignant neoplasms with esophageal cancer (SMN-EC) after hematologic malignancy. Methods: Data of patients diagnosed with SMN-EC after hematologic malignancy between 1995 and 2014 treated non-surgically were extracted retrospectively from our hospital database. Results: Sixteen patients were eligible for enrollment. Six patients had a history of hematopoietic stem cell transplantation, 6 for chemotherapy, and 2 for chemoradiotherapy to treat hematologic malignancy. For the treatment of SMN-EC, 5 patients, 6 patients, and 5 patients were treated by chemotherapy, chemoradiotherapy, and radiotherapy alone, respectively. During the treatment for SMN-EC, grade ≥3 hematologic toxicities were neutropenia (n=10, 62.5%), anemia (n=7, 43.8%), and thrombocytopenia (n=5, 31.3%). Grade ≥3 non-hematologic toxicities included esophagitis (n=8, 50%), oral mucositis (n=4, 25%), febrile neutropenia (n=3, 18.8%), and sepsis (n=1, 6.3%). One patient who received chemoradiotherapy died of treatment-related interstitial pneumonia. Conclusions: Patients who receive chemotherapy and/or radiotherapy for SMN-EC after hematologic malignancy might be at elevated risk of TRAEs. Non-surgical treatment of SMN-EC patients with a history of hematologic malignancy should be carefully monitored for potential severe toxicity.