Patient characteristics
A total of 17 STS patients treated with nab-paclitaxel/ gemcitabine were enrolled in this study. Basic patient characteristics are shown in Table 1. The cohort included 11 (64.71%) men and 6 (35.29%) women. The average patient age was 38.71±17.35 years. All patients had stage IV disease. All patients were previously treated with doxorubicin-based or other chemotherapy. The primary tumor site varied significantly. and although primary tumor sites were distributed throughout the body, they were mainly situated in the extremities. The histological subtypes were also markedly different. The most common subtype being epithelioid sarcoma (n=5), followed by angiosarcoma (n=3), rhabdomyosarcoma (n=3), undifferentiated pleomorphic sarcoma (n=2), fibrosarcoma(n=2), leiomyosarcoma (n=1), and primitive neuroectodermal tumor (n=1).
Table 1 Patient demographics and characteristics
Patient No.
|
Age
(years)
|
ECOG PS
|
Histological subtype
|
Stage
|
Primary site
|
Metastatic site
|
Previous DOX chemotherapy
|
Response
|
PFS (Months)
|
1
|
22
|
0
|
Epithelioid sarcoma
|
IV
|
Extremities
|
Lung and bone
|
Yes
|
PR
|
6
|
2
|
30
|
1
|
Epithelioid sarcoma
|
IV
|
Extremities
|
Lung and lymph nodes
|
Yes
|
PR
|
11
|
3
|
31
|
1
|
Epithelioid sarcoma
|
IV
|
Extremities
|
Lung and bone
|
Yes
|
PR
|
6
|
4
|
25
|
0
|
Epithelioid sarcoma
|
IV
|
Extremities
|
Bone
|
Yes
|
SD
|
9
|
5
|
18
|
1
|
Epithelioid sarcoma
|
IV
|
Extremities
|
Lung
|
Yes
|
PD
|
1.5
|
6
|
24
|
1
|
Angiosarcoma
|
IV
|
Extremities
|
Bone
|
Yes
|
CR
|
12
|
7
|
36
|
0
|
Angiosarcoma
|
IV
|
Extremities
|
Lung
|
Yes
|
SD
|
8
|
8
|
63
|
0
|
Angiosarcoma
|
IV
|
Extremities
|
Lung
|
Yes
|
PR
|
7
|
9
|
29
|
0
|
Rhabdomyosarcoma
|
IV
|
Head
|
Lung and Soft tissue
|
Yes
|
PR
|
9
|
10
|
22
|
0
|
Rhabdomyosarcoma
|
IV
|
Trunk
|
Bone
|
Yes
|
SD
|
6
|
11
|
33
|
0
|
Rhabdomyosarcoma
|
IV
|
Extremities
|
Lung
|
Yes
|
PD
|
3
|
12
|
65
|
1
|
UPS
|
IV
|
Extremities
|
Lung
|
Yes
|
SD
|
6
|
13
|
58
|
0
|
UPS
|
IV
|
Pelvis
|
Lung
|
Yes
|
PD
|
1.3
|
14
|
64
|
1
|
Fibrosarcoma
|
IV
|
Trunk
|
Lung
|
Yes
|
PR
|
9
|
15
|
61
|
0
|
Fibrosarcoma
|
IV
|
Extremities
|
Lung
|
Yes
|
PD
|
1
|
16
|
52
|
0
|
Leiomyosarcoma
|
IV
|
Extremities
|
Lung
|
Yes
|
PD
|
2
|
17
|
25
|
1
|
PNET
|
IV
|
Trunk
|
Lung
|
Yes
|
SD
|
3
|
Abbreviations: ECOG PS, Eastern Cooperative Oncology Group performance status; UPS, undifferentiated pleomorphic sarcoma; PNET, primitive neuroectodermal tumor; DOX, doxorubicin-based; PR, partial response; SD, stable disease; PD, progressive disease; CR, complete response. PFS, progression-free survival.
Effectiveness of therapy
Of the 17 patients, 1 patient with angiosarcoma achieved complete response, 6 patients had partial response, 5 patients achieved stable disease (SD), and 5 patients had PD (Tables 1 and 2; Figure 1). The ORR was 41.2%, the DCR was 70.6%, the m-PFS was 6 months (95% CI, 2–9 months), and the 6-months PFS rate was 64.71% (Table 3; Figure 1). The average change in target lesion diameter from baseline was -19.06±45.74% (Figure 1).
Table 2 Responses of various histological subtypes to treatment
Histological subtypes
|
Number of patients
|
|
CR
|
PR
|
SD
|
PD
|
Epithelioid sarcoma (n=5)
|
0
|
3
|
1
|
1
|
Angiosarcoma (n=3)
|
1
|
1
|
1
|
0
|
Rhabdomyosarcoma (n=3)
|
0
|
1
|
1
|
1
|
UPS (n=2)
|
0
|
0
|
1
|
1
|
Fibrosarcoma (n=2)
|
0
|
1
|
0
|
1
|
Leiomyosarcoma
|
0
|
0
|
0
|
1
|
PNET
|
0
|
0
|
1
|
0
|
Total
|
1
|
6
|
5
|
5
|
Abbreviations: CR, complete response; PR, partial response; SD, stable disease; PD, progressive disease; UPS, undifferentiated pleomorphic sarcoma; PNET, primitive neuroectodermal tumor.
Table 3 Clinical effectiveness
Characteristics
|
Data
|
ORR
|
41.20%
|
DCR
|
70.60%
|
M-PFS (months)
|
6 (95%CI: 2-9)
|
6 months PFS rate
|
64.71%
|
Notes: Data are presented as percentages or means.
Abbreviations: ORR, the objective response rate; DCR, the disease control rate; m-PFS, the median progression-free survival.
Toxicity and safety
In general, nab-paclitaxel/ gemcitabine chemotherapy was relatively well tolerated. As shown in Table 4, the most common grade 1or 2 AEs were alopecia (88.2%, 15/17), neutropenia (64.7%, 11/17), fatigue (52.9%, 9/17), anemia (47.1%, 8/17), and nausea (41.2%, 7/17). The grade 3 or 4 AEs were not common, but included neutropenia (17.6%), fatigue (11.8%), anemia (11.8%), leukopenia (11.8%), nausea (5.9%), peripheral neuropathy (5.9%), diarrhea (5.9%), and thrombocytopenia (5.9%). No treatment-related deaths occurred.
Table 4 Adverse events
Adverse events
|
Grade 1-2
|
Grade 3-4
|
Alopecia
|
88.2% (15/17)
|
|
Neutropenia
|
64.7% (11/17)
|
17.6% (3/17)
|
Fatigue
|
52.9% (9/17)
|
11.8% (2/17)
|
Anemia
|
47.1% (8/17)
|
11.8% (2/17)
|
Nausea
|
41.2% (7/17)
|
5.9% (1/17)
|
Leukopenia
|
35.3% (6/17)
|
11.8% (2/17)
|
Peripheral neuropathy
|
29.4% (5/17)
|
5.9% (1/17)
|
Anorexia
|
29.4% (5/17)
|
|
Diarrhea
|
23.5% (4/17)
|
5.9% (1/17)
|
Thrombocytopenia
|
23.5% (4/17)
|
5.9% (1/17)
|
Alkaline phosphatase increased
|
17.6% (3/17)
|
|
Fever
|
11.8% (2/17)
|
|
Abdominal pain
|
11.8% (2/17)
|
|
Pneumonitis
|
5.9% (1/17)
|
|
Notes: Data are presented as percentages (number events/total).