Real-world treatment attrition rates in advanced esophagogastric cancer

Table 1 Baseline characteristics of 245 patients with advanced esophagogastric cancer who received at least one line of systemic therapy

	Only one line of therapy (n = 122)	At least two lines of therapy (n = 123)	P value
Median age (IQR)	68 (61.7-73.7)	62 (56.1-70.6)	< 0.05
Gender, n (%)			0.37
Male	96 (79)	90 (73)
Female	26 (21)	33 (27)
Ethnicity, n (%)			0.59
Caucasian	101 (83)	95 (77)
Asian	15 (12)	21 (17)
East Asian	6 (5)	6 (5)
Other	0	1 (1)
Histology, n (%)			0.92
Adenocarcinoma	96 (79)	95 (77)
Squamous cell carcinoma	9 (7)	11 (9)
Signet ring cell	17 (14)	17 (14)
HER2 status, n (%)			0.41
Positive	27 (22)	37 (30)
Negative	70 (57)	72 (59)
Unknown	25 (20)	14 (11)
MMR status by IHC, n (%)			1.0
Deficient MMR	1 (1)	1 (1)
Proficient MMR	34 (28)	55 (45)
Unknown	87 (71)	67 (54)
Grade, n (%)			0.14
Well	3 (2)	5 (4)
Moderate	30 (25)	42 (34)
Poor	58 (48)	45 (37)
Unknown	31 (25)	31 (25)
Site of primary, n (%)			0.44
Gastric	44 (36)	46 (37)
GEJ/esophagus	78 (64)	77 (63)
Location of metastases, n (%)
Lymph node	64 (52)	54 (44)	0.20
Lung	29 (24)	28 (67)	0.88
Liver	39 (32)	50 (41)	0.18
Peritoneum	31 (25)	23 (19)	0.22
Other	28 (23)	16 (13)	0.05
Disease presentation, n (%)			0.89
De novo disease	87 (71)	89 (72)
Recurrent disease	35 (29)	34 (28)
Previous chemoradiation, n (%)	32 (26)	29 (24)	0.66
Previous resection, n (%)	27 (22)	24 (20)	0.64
ECOG at baseline, n (%)			0.14
0	11 (9)	20 (16)
1	83 (68)	84 (68)
2	28 (23)	19 (15)
Best response to first-line treatment, n (%)			< 0.05
Complete response	6 (5)	4 (3)
Partial response	33 (27)	46 (37)
Stable disease	20 (16)	38 (31)
Progressive disease	58 (48)	33 (27)
Unknown	5 (4)	2 (2)
Median duration of first-line treatment	2.7 (0.9-6.1)	5.00 (3.5-9.8)	< 0.05
Reason for discontinuation of first-line treatment, n (%)			0.02
Progression	82 (67)	101 (82)
Toxicity	15 (12)	4 (3)
Other	23 (19)	17 (14)
Unknown	2 (2)	1 (1)

IQR: Interquartile range; HER2: Human epidermal growth factor receptor 2; MMR: Mismatch repair; IHC: Immunohistochemistry; GEJ: Gastroesophageal junction.

Table 2 Treatment details for patients who received at least two lines of systemic therapy

Second-line chemotherapy backbone [n = 123, n (%)]
5-FU/oxaliplatin	9 (7)
5-FU/irinotecan	21 (17)
5-FU/cisplatin	3 (2)
Ramucirumab/paclitaxel	76 (62)
Docetaxel	8 (7)
Capecitabine	2 (2)
Irinotecan	3 (2)
Trastuzumab alone	1 (1)
Best response to second-line treatment, n (%)
Complete response	2 (2)
Partial response	17 (14)
Stable disease	27 (22)
Progressive disease	73 (59)
Unknown	4 (3)
Median duration of second-line treatment (mo)	2.8 (1.4-5.7)
Reason for discontinuation of second-line treatment, n (%)
Progression	100 (81)
Toxicity	7 (6)
Other	12 (10)
Unknown	11 (9)
Third-line chemotherapy backbone [n = 40, n (%)]
5-FU	1 (2.5)
5-FU/irinotecan	14 (35)
5-FU/oxaliplatin	1 (2.5)
Docetaxel	2 (5)
Irinotecan	8 (20)
Ramucirumab/paclitaxel	11 (28)
Pembrolizumab	1 (2.5)
Nivolumab	1 (2.5)
Durvalumab/Tremelimumab	1 (2.5)
Best response to third-line treatment, n (%)
Complete response	1 (2.5)
Partial response	7 (18)
Stable disease	6 (15)
Progressive disease	25 (63)
Unknown	1 (2.5)
Median duration of third-line treatment (mo)	1.9 (0.9-4.4)
Reason for discontinuation of third-line treatment, n (%)
Progression	34 (85)
Toxicity	0
Other	3 (8)
Unknown	3 (8)
Fourth-line chemotherapy backbone [n = 6, n (%)]
5-FU	1 (17)
5-FU/oxaliplatin	2 (33)
5-FU/irinotecan	1 (17)
5-FU/cisplatin	1 (17)
Nivolumab	1 (17)
Best response to fourth-line treatment, n (%)
Complete response	0
Partial response	0
Stable disease	1 (17)
Progressive disease	5 (83)
Median duration of fourth-line treatment (mo)	2.57 (2.08-3.75)
Reason for discontinuation of fourth-line treatment, n (%)
Progression	6 (100)
Toxicity	0
Other	0
Unknown	0

5-FU: 5-fluorouracil.

Table 3 Multivariable Cox regression analysis for overall survival

	Hazard ratio (95%CI)	P value
Gender (male vs female)	1.07 (0.77-1.48)	0.69
Baseline ECOG (continuous)	1.33 (1.02-1.73)	0.04
Recurrent disease (vs de novo)	0.86 (0.62-1.19)	0.37
Duration of first-line treatment	1.00 (1.00-1.002)	0.09
Lines of treatment	0.61 (0.50-0.74)	< 0.01

ECOG: Eastern Cooperative Oncology Group.