Page 102 - ARNM-3-2

Advances in Radiotherapy
& Nuclear Medicine A dosimetric research on iodine-125 seed implantation

reduced to <10 mm. The partial remission (PR) category expanded by 5 mm (CTV 5mm ), the D parameter showed
90
was indicated when the total diameter of all target lesions a significant difference compared to immediate post-
was reduced by at least 30% compared to baseline. operative measurements (p=0.03, p<0.05), whereas other
Progressive disease (PD) was defined as an increase of at parameters did not demonstrate statistically significant
least 20% in the total diameter of target lesions, using the differences (Tables 1-4).
smallest recorded total diameter as a reference (including
baseline if it is the smallest). In addition, the absolute 4. Discussion
increase in sum must be at least 5 mm, or the appearance Surgery is the first choice and the most effective treatment
of one or more new lesions was also classified as PD. The for patients with early-stage NSCLC. The extent of lung
stable disease (SD) category was assigned when there was resection, bronchial resection, and lymph node dissection
insufficient reduction to qualify as PR and insufficient is determined by tumor location and stage, with surgical
increase to qualify as PD. guidelines requiring a bronchial resection margin of at
Adverse reactions after seed implantation were least 2 cm from the tumor. In external radiotherapy, a
evaluated according to the grading standard for acute margin is usually added to the GTV to define the CTV,
radiation injury and the grading scheme for late radiation
injury. 13 Table 1. The dosimetry parameters of Groups A and B
2.5. Statistical methods Group Vol (cc) D90 (Gy) V100 (%) V150 (%) V200 (%)
CTV
Statistical Package for the Social Sciences 25.0 statistical
software (IBM, United States) was used for data analysis. A 41.5±6.3 164.5±8.3 94.5±1.0 75.7±3.3 54.4±4.7
Independent sample t-test was used to compare Vol and B 49.8±9.2 142.2±1.3 91.6±1.1 62.7±3.7 37.8±3.9
related dosimetric parameters between Groups A (CR) CTV5mm
and B (non-CR group). There were 14 patients in Group A A 75.3±10.0 103.8±4.5 74.8±2.7 49.6±3.4 32.7±3.2
and 17 patients in Group B. Independent sample t-test B 82.9±14.9 87.9±1.7 66.3±1.9 39.7±2.2 22.2±2.0
was used to compare the CTV 5mm and CTV 1cm and their CTV1cm
corresponding dosimetric parameters of Groups A and B, A 136.3±17.5 60.7±3.8 44.7±3.0 28.8±2.5 18.7±2.0
respectively.
B 131.0±21.1 55.5±1.2 43.2±1.6 24.9±1.5 14.4±1.4
3. Results Notes: Data are expressed as mean±standard deviation; CTV: Clinical
target volume; CTV5mm: Clinical target volume5mm; CTV1mm: Clinical
3.1. Efficacy determination target volume1mm; Vol: Target volume; D90: Minimum peripheral dose
received by 90% of the target volume; V100: Percentage of target volume
In Group A, the CR rate was 100% (14/14), with no cases covered by 100% of the prescription dose; V150: Percentage of target
of PR, SD, or PD (0/14). In Group B, the CR rate was 0% volume covered by 150% of the prescription dose; V200: Percentage of
(0/17), whereas the PR rate was 71% (12/17), the SD rate target volume covered by 200% of the prescription dose.
was 24% (4/17), and the PD rate was 5% (1/17).
Table 2. Statistics for dosimetry parameter comparison
3.2. Adverse reactions between Groups A and B
Pneumothorax occurred in 10 patients (32%) during Parameter F Significance t p 95% confidence
the operation, with three patients exhibiting moderate interval
pneumothorax (10%), all of whom were successfully Lower Upper
treated with closed thoracic drainage. Intrapulmonary limit limit
hemorrhage was observed in 13 cases (42%), whereas Vol 0.912 0.348 −0.747 0.461 −31.221 14.527
hemoptysis occurred in 4 cases (13%), both of which 8.699 0.006 2.655 0.013 5.094 39.508
resolved following hemostatic treatment. Notably, no cases D90
of radiation pneumonitis or particle translocation were V100 0.119 0.733 1.947 0.062 −0.150 5.950
reported, and no complications of grade 3 or above were V150 0.192 0.665 2.655 0.013 2.975 23.065
observed. V200 0.363 0.552 2.708 0.011 4.041 29.145
Notes: Vol: Target volume; D90: Minimum peripheral dose received by
3.3. Independent sample t-test results 90% of the target volume; V100: Percentage of target volume covered
There was no significant difference in dosimetric by 100% of the prescription dose; V150: Percentage of target volume
covered by 150% of the prescription dose; V200: Percentage of target
parameters between Group A and Group B immediately volume covered by 200% of the prescription dose.
following the operation. However, when the GTV was Abbreviations: F: F-statistic; t: t-statistic; p: p-value.

Volume 3 Issue 2 (2025) 94 doi: 10.36922/arnm.8512