A cure model survival analysis of patients affected by small intestinal neuroendocrine neoplasms: the Bologna ENETS center experience.

PURPOSE: The primary end-point was to evaluate the cure fraction. Secondary end-points were to investigate the time to cure, the excess of death risk, the probability of cure and the factors related to these parameters.

METHODS

Retrospective study of an ENETS database regarding patients affected by Si-NENs. For each patients, clinical, pathological and follow-up data were collected. The survival analysis was made using a novel approach: the cure model approach.

RESULTS

The cure fraction was 92.1%. The death risk, time to cure and the probability of cure were 6/1000 person-years, 3.6 years and 98.2%, respectively. The independent factors influencing these parameters were the grading and the R status (P = 0.041 and P = 0.017, respectively). Patients affected by Si-NENs G2 increased the death risk and time to cure respect to Si-NENs G1 (51 versus 6 per 1000 person-years and 5.1 versus 3.6 years, respectively) as well as patients not operated respect to those radically resected (R0/1) (66 versus 1 per 1000 person-years and 4.8 versus 0.4 years, respectively). The probability of cure decreased (88.1 versus 97.8% and 80.4 versus 99.7%, respectively). R2 resection shows better results than no resection.

CONCLUSIONS

A large portion of patients affected by Si-NENs can be cured. The highest probability of cure regards patients with Si-NENs G1 who underwent to R0/R1 resection; the lower, those with Si-NENs G2 and no resection. R2 resection seems to be preferred respect to no resection.