In the era of
personalized medicine, systemic treatment with
chemotherapy in combination with targeted drugs, tailored according to RAS and BRAF status, has improved the survival of patients with metastatic
colorectal cancer (mCRC), but curative resection of
metastases provides the only chance of cure. Here, we present a 40-year-old male with rectal
adenocarcinoma and multiple bilateral synchronous liver
metastases who has achieved long-term remission with
multimodal treatment without resection of all metastatic lesions. This case emphasizes the need of repeated multidisciplinary team assessments and change of treatment intent if extraordinary responses are seen. The initial
therapy consisted of short-course
radiotherapy and surgery of the primary
tumor followed by
oxaliplatin-based
combination chemotherapy and
panitumumab with disease control intent. A complete radiologic response in >20 liver
metastases in segments II-VIII was obtained. A biopsy-verified relapse of 3 liver
metastases occurred at 9 months of treatment pause. Subsequently, major liver resection of 8 lesions was performed (4 with
adenocarcinoma and 4 with
cicatrix showing the challenge of disappearing lesions), followed by 6 months of adjuvant-like
therapy. No relapse in MRI, PET, or CT has been noted since liver resection 6 years ago. Comprehensive genomic profiling of the primary
tumor and liver
metastases had similar driver mutations representing a low level of gene alteration and low diversity, possibly explaining the exceptional treatment response.