Clinical response to adding pyrotinib to pembrolizumab and lenvatinib for HER2-positive advanced intrahepatic cholangiocarcinoma: a case report.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a highly lethal hepatobiliary cancer, and very few patients can undergo surgery. The prognosis of advanced ICC is poor, especially in patients who progress after first-line chemotherapy, with a median overall survival of less than 10 months. CASE PRESENTATION: A 64-year-old male was diagnosed with advanced intrahepatic cholangiocarcinoma with ERBB2 (HER2) 3 + amplification determined by tissue-based testing and confirmed by next-generation sequencing. The patient was treated with pyrotinib added to pembrolizumab and lenvatinib after progressing with pyrotinib and tegafur and responded very well with regression of the tumor on imaging as well as normalization of tumor marker levels without serious adverse events. PET-CT after 6 months of treatment showed a partial response. The progression-free survival with second-line treatment was 17 months. For the third line of therapy, lenvatinib and pembrolizumab were used in combination with bevacizumab. Currently, he has had stable disease for approximately 6 months during third-line treatment. CONCLUSION: Adding pyrotinib to pembrolizumab and lenvatinib may represent a promising strategy for advanced ICC patients who have high levels of HER2.