Chemotherapy After Surgery for Advanced Appendix Cancer: Is It Needed?

Abdominal Cancers Alliance
Oct 6
2 min read

Updated: Oct 7

Ekaterina Baron, Armando Sardi, Mary Caitlin King, Andrei Nikiforchin, Felipe Lopez-Ramirez, Carol Nieroda, Vadim Gushchin, Panayotis Ledakis

Adjuvant chemotherapy for high-grade appendiceal cancer after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy. European Journal of Surgical Oncology 49, (2023) 179-187.

https://pubmed.ncbi.nlm.nih.gov/36253240/

Summary:

Researchers studied whether giving traditional chemotherapy after surgery and heated chemotherapy in the belly (CRS/HIPEC) helps people with advanced, high-grade appendix cancer live longer. They followed 180 patients and found that those who received extra chemotherapy did not live longer than those who did not. The results were the same even for patients with more aggressive cancers or higher tumor burden. This suggests that appendix cancers behave differently from colon cancers and may not respond to the same chemotherapy. For now, the most effective treatment remains CRS/HIPEC, and whether to add chemotherapy afterward should be a personal decision made with your care team.

Background

High-grade appendiceal cancer (a rare type of appendix cancer that spreads inside the abdomen) is often treated with CRS/HIPEC, a surgery to remove visible cancer followed by heated chemotherapy inside the abdomen. Even after this treatment, the cancer can return. Many doctors add “regular” intravenous chemotherapy afterward (called adjuvant chemotherapy) to try to lower the risk. But until now, it hasn’t been clear whether this extra chemotherapy actually helps patients live longer.

What Was Done

The team looked back at 180 patients treated at Mercy Medical Center in Baltimore, Maryland between 1999–2020. All patients had stage IVA/B high-grade appendiceal cancer and had undergone successful CRS/HIPEC. Some patients received additional chemotherapy afterward (77 patients), and some did not (103 patients). The researchers compared how long patients lived and how quickly the cancer came back in both groups.

What They Found

Survival was similar whether patients had extra chemotherapy or not.
- Patients who had chemotherapy lived a median of 53 months.
- Patients who did not have chemotherapy lived a median of 75 months.
- This difference was not statistically significant (meaning it could have been due to chance).
Chemotherapy did not show benefits in any subgroup of patients, including those with:
- signet ring cell tumors (a more aggressive type),
- cancer in lymph nodes, or
- higher tumor burden inside the abdomen.
The type of chemotherapy used (oxaliplatin-based, irinotecan-based, or 5-FU) didn’t make a difference either.
Timing of chemotherapy (whether started earlier or later after surgery) also didn’t clearly affect outcomes.

Why It Matters for Patients

For patients with advanced high-grade appendiceal cancer, giving traditional colon cancer chemotherapy after CRS/HIPEC did not show a survival benefit.
This suggests appendiceal cancers behave differently than colon cancers, and treatments effective for colon cancer may not work the same way.
More research—especially collaborative, multi-center studies—is needed to find better strategies.
Doctors should carefully weigh the risks and benefits before recommending chemotherapy after CRS/HIPEC in these patients.

Bottom Line

If you or a loved one has advanced appendix cancer treated with CRS/HIPEC, this study suggests that additional chemotherapy may not necessarily improve survival. Every case is unique, so it’s important to discuss options with your care team. Future research may help identify which patients could benefit most from extra treatments.