Immune checkpoint inhibitor-based chemotherapy for granulocyte-colony stimulating factor-producing advanced...

Granulocyte-colony stimulating factor (G-CSF)-producing esophageal squamous cell carcinoma (ESCC) is a rare and highly aggressive malignancy. Currently, no specific treatment approach has been established for G-CSF-producing tumors, including those in the lungs, esophagus, and other organs. Here, we present three cases of advanced G-CSF-producing ESCC treated with immune checkpoint inhibitor (ICI) combination chemotherapy.

Case 1: A 52-year-old man was diagnosed with G-CSF-producing ESCC with multiple lymph node and lung metastases. First-line chemotherapy with fluorouracil (5-FU), cisplatin, and pembrolizumab (FP + PEM) led to significant tumor regression and normalization of inflammatory marker levels. The regimen was de-escalated to 5-FU and pembrolizumab, and the disease remains stable. Case 2: A 69-year-old man was diagnosed with G-CSF-producing ESCC with multiple lymph node metastases. FP + PEM therapy initially reduced the tumor burden, but disease progression occurred after four treatment cycles. The patient was switched to second-line weekly paclitaxel. Case 3: A 62-year-old man was diagnosed with G-CSF-producing ESCC with bone metastasis. FP + PEM therapy achieved partial response in the primary tumor, but bone metastasis progressed, requiring radiation and a switch to paclitaxel.

We report three cases of advanced G-CSF-producing ESCC treated with ICI combination chemotherapy. Although ICIs show promise, treatment resistance remains a challenge. Further research and additional case accumulation are needed to better understand their efficacy and optimize treatment strategies.