Table 1 Background factors of the patients

Gender

male

32

female

22

Age

67.4 ± 14.5 years

Disease

prostate cancer

1

pancreatic cancer

1

liver cancer

2

kidney cancer

2

head and neck cancer

4

colorectal cancer

5

breast cancer

5

other cancers

5

gastric cancer

7

lung cancer

11

heart disease

11

BMI

22.0 ± 3.33

PS

PS0

43

PS1

7

PS2

4

Diabetes

–

45

+

9

Smoking habit within one year

–

48

+

6

Drinking habit within one year

–

41

+

13

Creatinine

0.834 ± 0.260 mg/dL

ALT

23.5 ± 18.1 IU/L

Albumin

4.05 ± 0.625 g/dL

Amount of dental plaque

492.45 ± 383.17

Periodontal pocket depth

edenturous

6

< 6 mm

39

≥6 mm

9

Oral wetness before surgery

26.1 ± 2.94

Oral wetness after surgery

23.7 ± 5.08

Operation time

278 ± 177 min

Blood loss

411 ± 775 g

Feeding condition on the next day after surgery

normal food

10

stop feeding

38

intubation

6

Number of bacteria in the saliva before surgery (logarithm)

5.54 ± 0.52

Number of bacteria in the saliva after surgery (logarithm)

6.61 ± 0.91

Number of bacteria on the tongue before surgery (logarithm)

6.75 ± 0.601

Number of bacteria on the tongue after surgery (logarithm)

6.88 ± 0.66