Incidence, Risk Factors, and Outcomes from Conversion of Low-Grade to High-Grade Appendiceal Neoplasms for Patients Undergoing Multiple Cytoreductive Surgeries with Hyperthermic Intraperitoneal Chemotherapy

Impact of myometrium invasion on survival outcomes following cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC)

INTRODUCTION

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is an effective surgical intervention for peritoneal surface malignancy. The effect of myometrium invasion on outcomes is unknown.

METHODS

Retrospective review of our institutional registry with analysis of CRS-HIPEC cases involving a hysterectomy. Compared cases with myometrium invasion versus those without invasion. Primary outcome was survival as measured by overall survival (OS) and disease-free survival (DFS). Secondary outcome was the evaluation of risk factors for myometrium invasion based on multivariate analysis.

RESULTS

A total of 126 cases of CRS-HIPEC involving a hysterectomy were identified. Ninety-seven cases (76.9%) had no myometrium invasion and the remaining 29 cases (23.1%) had malignant invasion. The presence of myometrial invasion was a significant negative survival prognostic factor. The OS was halved with mean survival times of 2.8 (±2.3) versus 5.8 (±4.7) years for cases with and without invasion, respectively (p = 0.002). Five-year OS rates were also inferior with myometrium invasion at 17.4% versus 53.8% (odds ratio [OR] = 0.181, 95% confidence interval [CI]: 0.057-0.580, p = 0.002). A similar trend was present with DFS with mean survival times of 1.4 (±0.9) versus 3.7 (±3.9) years for noninvasion and invasion cases (p = 0.009). The 5-year DFS rates were 0% versus 34.8% (OR = 0.652, 95% CI: 0.549-0.775, p = 0.004). Secondary analysis significantly associated several risk factors with myometrium invasion to include lymph node positivity (OR = 2.539, 95% CI: 1.074-6.003, p = 0.012), colorectal primary tumors (OR = 2.248, 95% CI: 1.094-5.161, p = 0.035), and high-grade tumors (OR = 2.160, 95% CI: 1.080-4.820, p = 0.038).

CONCLUSION

Myometrium invasion is a significant negative prognostic factor for survival following CRS-HIPEC. Several risk factors are potentially predictive of identifying those at high-risk for myometrium invasion.

Timing of Repeat Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy for Recurrent Low-Grade Appendiceal Mucinous Neoplasms

BACKGROUND

Low-grade appendiceal mucinous neoplasm (LAMN) with peritoneal involvement is a common indication for cytoreductive surgery with heated intraperitoneal chemotherapy (CRS/HIPEC). With peritoneal recurrence, patients are increasingly being offered repeat CRS/HIPECs, however optimal timing for a second CRS/HIPEC remains unknown.

METHODS

A prospectively maintained 30-year database at our high-volume HIPEC center was analyzed retrospectively for patients with LAMNs and peritoneal recurrence receiving one or two CRS/HIPECs. Kaplan-Meier survival analysis, linear regression modeling, and Cox proportional hazards regression analyses were performed.

RESULTS

Overall, 143 patients with LAMNs who underwent CRS/HIPECs had confirmed postoperative peritoneal recurrence. Of these patients, 85 underwent one CRS/HIPEC and 58 underwent two CRS/HIPECs. The groups had significant differences in age, with younger patients more likely to undergo a second CRS/HIPEC (48.5 vs. 58.0 years; p < 0.001). The median overall survival (OS) for the group undergoing two CRS/HIPECs was approximately four times longer compared with the group undergoing one CRS/HIPEC (227.1 vs. 54.5 months; p < 0.0001). The time from recurrence to the second CRS/HIPEC was not significantly associated with OS from the time of the first operation. Instead, a shorter time between the first CRS/HIPEC and recurrence was significantly associated with shorter OS from the time of the first operation (p = 0.037).

CONCLUSION

In peritoneal LAMNs with recurrence, receiving two CRS/HIPECs was associated with better OS compared with receiving one CRS/HIPEC. Longer time to recurrence was a good prognostic factor. Delay between recurrence and second CRS/HIPEC had no apparent impact on OS from the first CRS/HIPEC; thus, immediate or delayed reoperative intervention are both reasonable approaches.