Peritoneal Recurrence Risk Calculator (SPACE-FLOT)

Select prediction model *

Patient demographics

Age (years) *

Gender *

BMI (kg/m²) *

Charlson Comorbidity Index *

Smoking status *

Functional status & fitness

ASA grade *

ECOG performance status *

Preoperative staging & treatment

Staging laparoscopy result *

Completed 4 neoadjuvant FLOT cycles

Clinical cT stage *

Clinical cN stage *

Tumour characteristics

Tumour epicentre *

Lauren histotype *

Histological grade *

Post-surgical pathology

Tumour regression grade (TRG) *

Adjuvant treatment *

Postoperative complication *

ypT stage (simplified) *

ypN stage (simplified) *

ypM stage *

Nodal yield (total nodes retrieved) *

Nodes with cancer (positive node count) *

Histological features

Lymphovascular invasion (LVI) present

Perineural invasion present

Resection margin involved (R1)

Predicted peritoneal recurrence risk

12 months

—

cumulative incidence

24 months

—

cumulative incidence

36 months

—

cumulative incidence

Predicted cumulative incidence of peritoneal recurrence

Patient curve (solid) vs. study cohort tertiles (dashed)

Risk summary table

Timepoint	Predicted CIF	Cohort risk tier (at 24 m)
12 months	—	—
24 months	—
36 months	—

Clinical disclaimer: This calculator provides predicted cumulative incidence of peritoneal recurrence based on a competing-risks regression model (Fine-Gray) derived from a multicentre cohort of patients treated with perioperative FLOT chemotherapy and curative-intent surgery for gastro-oesophageal cancer. Predictions are probabilistic estimates and should be interpreted alongside clinical judgement. This tool does not constitute a recommendation for or against any specific treatment. The model has not been externally validated.

Model performance metrics

Model	Optimism-corrected AUC at 24 m (95% CI)	n (complete case)
Baseline (preoperative)	0.738 (0.723–0.778)	2,238
Full (post-surgical)	0.802 (0.791–0.835)	2,238

Internal validation: 1,000-bootstrap optimism correction, clustered by site. Brier scores: baseline 0.118, full 0.116 at 24 months.