Computed tomography-based radiomic to predict resectability in locally advanced pancreatic cancer treated with chemotherapy and radiotherapy

Table 1 Baseline characteristics and treatment details

Characteristic	Value
No. of patients	71
Age, yr, median (IQR)	64.8 (57.1-69.6)
Sex, male, n (%)	41 (57.8)
ECOG, 0, n (%)	61 (85.9)
Primary tumour location, n (%)
Head	44 (62.0)
Body	25 (35.2)
Neck	2 (2.8)
Tumour size (mm), median (IQR)	40 (30-45)
Biliary stent, present, n (%)	25 (35.2)
CA19-9 (U/mL) at diagnosis	951 (± 1134)
CA19-9 (U/mL) after chemotherapy (before RAdAR)	106 (± 160)
Clinical T stage1, n (%)
T2	6 (8.5)
T3	11 (15.5)
T4	54 (76.0)
Clinical N stage1, n (%)
N0	34 (47.9)
N1	37 (52.1)
Pre-RAdAR chemotherapy regimen, n (%)
FOLFIRINOX	30 (42.3)
Gemcitabine + nab-paclitaxel	41 (57.7)
RAdAR approach, n (%)
SAbR	59 (83.2)
HART	12 (16.9)
Delivery technique, n (%)
RapidArc® Technology	55 (77.5)
TomoTherapy® System	16 (22.5)
Resected patients2, n (%)	19 (26.8)
R status3, n (%)
R0	12 (63.2)
R1	7 (36.8)

¹Per the AJCC staging system, eighth edition.

²Exploratory laparotomy in 32 patients (45.1%), resection/exploration ratio 59.4%.

³Among resected patients, n = 19.

CA: Celiac artery; CHA: Common hepatic artery; FOLFIRINOX: Fluorouracil, leucovorin, oxaliplatin; HART: Hypofractionated ablative radiotherapy; IQR: Interquartile range; PV: Portal vein; SMA: Superior mesenteric artery; SAbR: Stereotactic ablative radiation therapy; SMV: Superior mesenteric vein.

Table 2 Selected features, P value from Wilcoxon test, adjust P value for Bonferroni correction, and LASSO regression coefficients (for each variable)

Variable name	P value Wilcoxon	P value corrected	LASSO slope
lbp.3D.m1_glrlm_LongRunLowGrayLevelEmphasis	1.01E-09	4.82E-07	-0.146
wavelet.LLL_glcm_Imc2	1.17E-06	5.61E-04	0.039
lbp.3D.m2_glszm_GrayLevelNonUniformityNormalized	4.01E-06	1.92E-03	0.113
exponential_glrlm_RunLengthNonUniformityNormalized	4.02E-06	1.92E-03	0.056