Stage IV colorectal cancer: Evaluating current and future treatment modalities

In the Netherlands, over 10,000 people are diagnosed with colorectal cancer (CRC) every year. More than 20% already have metastases (stage IV CRC) at the time of diagnosis, another 20% of patients develop them in the following years. Approximately 85% of patients with metastases have died from the disease within 5 years from diagnosis. For patients with only liver metastases and/or lung metastases, the survival rate is better than patients with metastases elsewhere or disseminated. In some of these patients, treatment even resulting in a long period without evidence of disease.

This dissertation discusses various aspects of metastatic colorectal carcinoma, with a focus on the different treatment strategies for patients with liver or lung metastases. The impact of the Dutch national bowel cancer screening is evaluated in Chapter 2. In Chapters 3 to 5 different treatment sequences and treatment techniques for liver metastases are compared. In Chapter 6 the current treatment strategies for lung metastases are evaluated. Chapter 7 shows the results of clinical trial investigating of an experimental treatment with combined intra-arterial chemopump chemotherapy and systemic chemotherapy for patients with unresectable or borderline resectable liver metastases.

In conclusion, the national population screening program has already attributed to the decrease in actual number of new stage IV CRC diagnoses and is expected to positively influence stage IV CRC incidence rates and treatment options even more over time. Treatment of colorectal cancer is an ongoing process in which new techniques and treatment sequences are being investigated and implemented to improve stage IV CRC survival rates and short-term outcomes. The newly introduced combination treatment, hepatic intra-arterial chemotherapy with concomitant systemic therapy, is feasible in the Netherland. A currently initiated subsequent randomized controlled trial will establish its role in Dutch metastatic colorectal cancer treatment.