Definitive chemoradiotherapy and salvage chemotherapy for patients with isolated locoregional recurrence after radical resection of primary pancreatic cancer

Figures & data

Table 1 Patient characteristics

Characteristics		Value
Total		31
Gender	Female/male	11/20
Age	Medium (range)	62 (44–80)
PS	0/1	7/24
Tumor location	Head/uncinate process Body and tail	14 17
Pathological stage (AJCC 8th) Pathological type Grade LVI Perineural invasion Margin status Smad4 DFI [months]	T1/2/3/4/NA N 0/1/2/NA G1/G2/G3/NA -/+/NA -/+/NA R0/R1/R2 -/-or+/+/NA Medium(range)	2/11/7/2/9 15/8/4/4 3/19/7/2 11/9/11 1/25/5 31/0/0 9/2/4/16 7.4 (0.2–44.6)
Preoperative CA19-9 (U/mL)	Medium Range NA	306.9 <0.6–>1000 11
Pre-RT CA19-9 (U/mL)	Medium	96.4
Recurrent site	Range NA Local/regional/both	<0.6–>1000 2 15/8/8

Abbreviations: AJCC, American Joint Committee on Cancer; LVI, lymphatic vessel invasion; DFI, disease-free interval; RT, radiotherapy; NA, not available.

Table 2 Treatment details

		Value
Radiotherapy
PTV-G dose (Gy)	Medium Range	56 54–60.2
GTV volume (cm^3)	Medium Range	36.0 6.9–176.5
Chemotherapy
Neoadjuvant
Yes		7
No		24
Adjuvant
Yes		28
No		3
Adjuvant chemo duration (months)	Medium Range	5.3 1.23–26.83
Pre-RT
Yes		9
No		22
Total cycles of chemotherapy (neoadjuvant+adjuvant+pre-RT)	Medium Range	6 2–13
Concurrent
Yes		24
No		7
IVC
GEM		2
OXA+CPT11		1
OC
S-1		16
Capecitabine		5
Post-RT
Yes		20
No		11

Abbreviations: PTV, planning target volume; GTV, gross tumor volume; IVC, intravenous chemotherapy; OC, oral chemotherapy; GEM, gemcitabine; OXA, oxaliplatin; CPT11, irinotecan; RT, radiotherapy.

Table 3 Response evaluation and survival analysis

	Value
Complete remission Stable disease Progressive disease	1 (3.2%) 24 (77.4%) 6 (19.4%)
Tumor progression Both local and systemic Local only Systemic only	2 (6.5%) 4 (12.9%) 6 (19.4%)
Medium (95% CI) OS from surgery (months)	28.3 (20.7–35.9)
Medium (95% CI) OS from radiotherapy (months)	23.6 (8.3–39.0)
Medium (95% CI) FFLP (months)	12.0 (0.1–23.9)

Abbreviations: OS, overall survival; FFLP, freedom from locoregional progression.

Table 4 Acute and late toxicities (CTCAE version 5.0)

Toxicity		Value
Hematological (Grade 2/3/4)	ALT AST Serum total bilirubin Direct bilirubin WBC ANC HGB PLT	0/0/0 0/0/0 2/1/0 2/0/0 2/1/0 2/2/0 4/0/0 0/0/0
Acute gastrointestinal toxicity (≥ Grade 2)	Anorexia, nausea, constipation, diarrhea, abdominal distension (Grade 2)	4
Late gastrointestinal toxicity (≥ Grade 2)	Gastric ulcer (Grade 3) Ileus (≥ Grade 2)	1 0

Abbreviations: ALT, alanine aminotransferase; AST, aspartate aminotransferase; WBC, white blood cell; ANC, absolute neutrophil count; HGB, hemoglobin; PLT, platelet.

Table 5 Univariate analysis for OS after RT using the Cox regression

Characteristics	Cut-off values	HR 95% CI	P value
Age	> 62 or ≤ 62	0.55 0.22 - 1.41	0.21
Gender	Female or male	1.03 0.40 - 2.64	0.94
BMI	> 21 or ≤ 21	0.50 0.17 - 1.48	0.21
pT	1-2 or 3-4	0.63 0.19 - 2.10	0.45
pN	0 or 1-2	1.27 0.46 - 3.64	0.64
Smad4	Negative or positive	1.04 0.28 - 3.92	0.95
Recurrent tumor  Location	Local or region/ local+region	0.68 0.27 - 1.69	0.41
DFI (months)	> 6 or ≤ 6	0.32 0.11 - 0.89	0.03
Pre-RT NLR	> 1.1 or ≤ 1.1	5.06 0.68 - 38.0	0.11
Pre-RT CA19-9 (U/ml)	> 97 or ≤ 97	2.28 0.88 - 5.93	0.09
Pre-RT CA19-9 (U/ml)	> 20 or ≤ 20	36.612 0.341 - 3932.241	0.131
Treatement
GTV volume (cm^3)	> 18 or ≤ 18	3.60 0.82 - 15.88	0.09
PTV-G dose (Gy)	> 55 or ≤ 55	0.66 0.26 - 1.65	0.38
Total cycles of chemotherapy before RT	> 3 or ≤ 3	0.63 0.24 - 1.66	0.35

Abbreviations: DFI, disease-free interval; RT, radiotherapy; NLR, neutrophil–lymphocyte ratio; GTV, gross tumor volume; PTV, planning target volume.

Figure 1 (A) Overall survival. (B) Overall survival in subgroups with disease-free interval (DFI) >6 months vs ≤6 months.