World J Oncol

World Journal of Oncology, ISSN 1920-4531 print, 1920-454X online, Open Access

Article copyright, the authors; Journal compilation copyright, World J Oncol and Elmer Press Inc

Journal website https://www.wjon.org

Original Article

Volume 15, Number 3, June 2024, pages 414-422

Three-Dimensional-Printed Template-Guided Radioactive Seed Brachytherapy via a Submental Approach for Recurrent Base of Tongue and Floor of Mouth Cancer

Figure 1. Treatment process schematic. (a) Cross-sectional view of the lesion. (b) Sagittal view of the lesion. (c) Preoperative planning. (d) 3D-printed template design. (e) Needle placement guided by the template. (f) CT scan post-needle placement. (g) CT scan post-seed placement. (h) Cross-sectional CT view showing seed distribution. 3D: three-dimensional; CT: computed tomography.

Figure 2. Six-month post-treatment follow-up CT (lesion no longer evident): (a-f) Sequential cross-sectional views of the lesion. (g) Sagittal view of the lesion.

Figure 3. Subgroup analysis survival curves. (a) Patients with tumor diameters ≤ 3.5 cm exhibited superior local control compared to those with diameters > 3.5 cm. (b) Patients without lesions outside the target area demonstrated marginally improved local control compared to those with lesions outside the target area. (c, d) Patients without lesions outside the target area showed enhanced disease control and overall survival compared to their counterparts.

Figure 4. Multivariate analysis forest plot. Lesions outside the target area were identified as independent predictors for disease control and overall survival. No independent predictors were associated with local control. LC: local control; OS: overall survival; DC: disease control; RT: radiotherapy.

**Table 1.** Patients Baseline and RSBT Information
Characteristics	Number	%
RSBT: radioactive seed brachytherapy; SCC: squamous cell carcinoma; ADC: adenocarcinoma; RT: radiotherapy.
Gender
Male	24	77
Female	7	23
Age (years) (median, range)	58 (4 - 81)
Primary diagnosis
Tongue (base) cancer	17	55
Cancer of the floor of the mouth	4	13
Hypopharyngeal cancer	3	10
Oropharyngeal cancer	3	10
Tongue sarcoma	2	6
Laryngeal cancer	1	3
Buccal cancer	1	3
Pathology
SCC	26	84
ACC	3	10
Sarcoma	2	6
RT history
Yes	27	87
No	4	13
RT dose (Gy) (median, range)	60 (30 - 75)
Surgical history
Yes	21	68
No	10	32
System treatment
Before RSBT	10	32
After RSBT	2	7
Both before and after RSBT	6	19
None	13	42
Activity of seeds (mCi) (median, range)	0.5 (0.4 - 0.6)
Number of seeds (median, range)	38 (17 - 78)
Number of needles (median, range)	10 (4 - 17)
Tumor diameter (cm) (median, range)	3.7 (2.1 - 4.8)
D90 (Gy) (median, range)	126.93 (95.7 - 169.55)
Lesions outside the target area
No	22	71
Region	2	6
Metastases	7	23

Table 1. Patients Baseline and RSBT Information

Characteristics

Number

RSBT: radioactive seed brachytherapy; SCC: squamous cell carcinoma; ADC: adenocarcinoma; RT: radiotherapy.

Gender

Male

Female

Age (years) (median, range)

58 (4 - 81)

Primary diagnosis

Tongue (base) cancer

Cancer of the floor of the mouth

Hypopharyngeal cancer

Oropharyngeal cancer

Tongue sarcoma

Laryngeal cancer

Buccal cancer

Pathology

SCC

ACC

Sarcoma

RT history

Yes

RT dose (Gy) (median, range)

60 (30 - 75)

Surgical history

Yes

System treatment

Before RSBT

After RSBT

Both before and after RSBT

None

Activity of seeds (mCi) (median, range)

0.5 (0.4 - 0.6)

Number of seeds (median, range)

38 (17 - 78)

Number of needles (median, range)

10 (4 - 17)

Tumor diameter (cm) (median, range)

3.7 (2.1 - 4.8)

D90 (Gy) (median, range)

126.93 (95.7 - 169.55)

Lesions outside the target area

Region

Metastases

**Table 2.** QOL Scores Before and After RSBT
Indicators	Before RSBT	6 months after RSBT	P
QOL: quality of life; RSBT: radioactive seed brachytherapy.
Pain	40.81 ± 7.314	30 - 55	50.65 ± 7.931	40 - 65	< 0.001
Appearance	47.74 ± 7.052	40 - 60	51.13 ± 4.418	45 - 60	0.003
Activity	59.84 ± 6.644	50 - 70	61.13 ± 6.286	50 - 75	0.133
Recreation	51.94 ± 6.413	40 - 60	54.03 ± 6.636	40 - 70	0.108
Swallowing	40.48 ± 6.104	30 - 50	50.65 ± 6.29	40 - 60	< 0.001
Chewing	42.58 ± 6.816	30 - 50	49.19 ± 5.492	40 - 60	< 0.001
Speech	59.68 ± 6.316	50 - 70	59.84 ± 4.913	50 - 70	0.861
Shoulder	79.35 ± 5.88	70 - 90	79.03 ± 5.541	70 - 90	0.325
Taste	29.84 ± 5.699	20 - 40	43.55 ± 5.195	35 - 55	< 0.001
Saliva	38.71 ± 6.451	30 - 50	37.9 ± 6.295	30 - 50	0.378
Mood	60.81 ± 6.337	50 - 70	67.58 ± 6.308	60 - 80	< 0.001
Anxiety	49.52 ± 5.966	40 - 60	50.81 ± 6.72	35 - 65	0.174

Table 2. QOL Scores Before and After RSBT

Indicators

Before RSBT

6 months after RSBT

Mean score

Range

Mean score

Range

QOL: quality of life; RSBT: radioactive seed brachytherapy.

Pain

40.81 ± 7.314

30 - 55

50.65 ± 7.931

40 - 65

< 0.001

Appearance

47.74 ± 7.052

40 - 60

51.13 ± 4.418

45 - 60

0.003

Activity

59.84 ± 6.644

50 - 70

61.13 ± 6.286

50 - 75

0.133

Recreation

51.94 ± 6.413

40 - 60

54.03 ± 6.636

40 - 70

0.108

Swallowing

40.48 ± 6.104

30 - 50

50.65 ± 6.29

40 - 60

< 0.001

Chewing

42.58 ± 6.816

30 - 50

49.19 ± 5.492

40 - 60

< 0.001

Speech

59.68 ± 6.316

50 - 70

59.84 ± 4.913

50 - 70

0.861

Shoulder

79.35 ± 5.88

70 - 90

79.03 ± 5.541

70 - 90

0.325

Taste

29.84 ± 5.699

20 - 40

43.55 ± 5.195

35 - 55

< 0.001

Saliva

38.71 ± 6.451

30 - 50

37.9 ± 6.295

30 - 50

0.378

Mood

60.81 ± 6.337

50 - 70

67.58 ± 6.308

60 - 80

< 0.001

Anxiety

49.52 ± 5.966

40 - 60

50.81 ± 6.72

35 - 65

0.174