784P - Prognostic nomograms for gestational and non-gestational choriocarcinoma: A population-based study

Background

Choriocarcinoma (CC) is a rare and highly aggressive cancer that exists in both the gestational (GCC) and non-gestational (NGCC) forms. Our research focused on comparing clinical outcomes, response to therapy, and prognostic determinants between these subtypes.

Methods

We analyzed data from the SEER database of patients diagnosed with CC between 2000 and 2020. Patients who were not diagnosed based on histology, previous history of cancer or other concurrent malignancies, or unknown data were excluded. The chi-square test were used for clinical features comparison. Kaplan-Meier estimation, log-rank tests, and Cox regression analyses were used to identify prognostic factors for overall survival (OS) and cancer specific survival (CSS). A nomogram was developed to predict 5-year OS, and a calibration curve was plotted to evaluate the agreement between the actual (observed) outcomes and expected probabilities.

Results

Of the 719 patients studied, 520 had GCC, and 200 had NGCC. Younger individuals were more common in the GCC. Additionally, a higher percentage of patients with NGCC were married (63.0% vs. 52.6%). AJCC stage distribution also differed; 47.4% of GCC patients were at stage I compared to 6.0% of NGCC patients. The surgery rates were higher in the NGCC group (79.5% vs. 60.9%). Patients with GCC had better OS than those with NGCC (93% vs. 71.2%, p = 0.001). CSS rates were 66.8% for NGCC and 65.2% for GCC (p = 0.001).

We developed a prognostic nomogram that integrated significant variables from multivariate analysis. For GCC, the model assigned the highest weight to radiation, followed by metastasis, and marital status. The AUC was 0.711 (95% CI: 0.64–0.79), and the calibration curves exhibited a mean error of 0.015. The NGCC model assigned the highest weights to metastasis, chemotherapy, and age. The AUC was 0.837 (95% CI, 0.77–0.9), and the calibration curve for 5-year survival demonstrated a mean error of 0.01.

Conclusions

Our study highlights the significant clinical and survival differences between GCC and NGCC patients. We developed prognostic nomograms tailored to each subtype to enhance prediction and support personalized management.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.