Cancer type, adjuvant therapy may influence early recurrence risk in peritoneal cancer
About one-third of patients with peritoneal metastasis experience recurrence within 12 months of undergoing cytoreductive surgery (CRS) and treatment with hyperthermic intraperitoneal chemotherapy (HIPEC), with cancer type and receipt of adjuvant treatment potentially affecting the risk of early recurrence, according to a study from Singapore.
“We established that [patients with] colorectal peritoneal metastases and patients who did not receive adjuvant chemotherapy were more likely to suffer early recurrence,” said the researchers.
Using a database of patients treated with CRS and HIPEC between April 2001 and February 2016 at the National Cancer Centre Singapore, researchers reviewed 144 patients with peritoneal metastases (median age 54 years, 73 percent female, 77 percent Chinese) of whom 30.6 percent had colorectal cancer, 36.8 percent had ovarian and primary peritoneal cancer, 24.3 percent had appendiceal cancer, 2.1 percent had mesothelioma, and 6.3 percent had other cancers. Patients with colorectal or appendiceal cancer received mitomycin C while those with ovarian or primary peritoneal cancer or mesothelioma received cisplatin as HIPEC. The risk of recurrence was compared with that of patients who did not develop recurrence or whose cancer recurred after 12 months.
Twenty-seven percent of patients (n=39) developed early recurrence of peritoneal malignancies, defined as a local or systemic recurrence occurring within 12 months of treatment with CRS and HIPEC.
Patients with appendiceal cancer had a lower risk of developing early recurrence compared with those with colorectal cancer (adjusted odds ratio [adjOR], 0.15, 95 percent confidence interval [CI], 0.043–0.502; p=0.002). [Int J Clin Oncol 2018;doi:10.1007/s10147-018-1301-8]
Patients who received adjuvant therapy after CRS also had a lower risk of developing early recurrence compared with those who did not receive any adjuvant treatment (adjOR, 0.32, 95 percent CI, 0.128–0.818; p=0.02). These findings were also demonstrated in a sub-analysis of patients with colorectal cancer, where those who received post-CRS adjuvant treatment had a lower risk of developing early recurrence compared with those who did not receive adjuvant treatment (OR, 0.19, 95 percent CI, 0.046–0.764; p=0.01).
“This is an important finding and a recommendation for adjuvant chemotherapy after CRS-HIPEC should be considered for patients with colorectal [cancer with] peritoneal metastases,” said the researchers.
After a median 26-month follow-up, patients who underwent CRS and HIPEC had a median overall survival (OS) of 63 months, with median OS for patients with colorectal cancer lower at 43 months, while median OS for patients with ovarian and primary peritoneal cancer was 63 months. Patients with early recurrence had a shorter OS than those without recurrence or who developed recurrence after 12 months (median OS, 27 vs 100 months).
“While some patients achieve long-term disease-free survival after CRS-HIPEC, there remains a group of patients with early recurrence. This is not only disappointing for the patient, but may also be detrimental as systemic therapy for these patients may have offered them a similar outcome, without the morbidity of a major procedure,” said the researchers.
“The origin of the peritoneal metastases and the use of adjuvant chemotherapy were the only significant risk factors we found for early recurrence. Improved results may be obtained with combined treatment of adjuvant chemotherapy after CRS and HIPEC,” they said.