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Radial displacement of clinical target volume in node negative head and neck cancer.

Jeon W, Wu HG, Song SH, Kim JI - Radiat Oncol J (2012)

Bottom Line: We use the second cervical vertebra body as a reference point to match each CT image set.There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03).In addition, the mean radial displacement increased with the distance from SB.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea.

ABSTRACT

Purpose: To evaluate the radial displacement of clinical target volume in the patients with node negative head and neck (H&N) cancer and to quantify the relative positional changes compared to that of normal healthy volunteers.

Materials and methods: Three node-negative H&N cancer patients and five healthy volunteers were enrolled in this study. For setup accuracy, neck thermoplastic masks and laser alignment were used in each of the acquired computed tomography (CT) images. Both groups had total three sequential CT images in every two weeks. The lymph node (LN) level of the neck was delineated based on the Radiation Therapy Oncology Group (RTOG) consensus guideline by one physician. We use the second cervical vertebra body as a reference point to match each CT image set. Each of the sequential CT images and delineated neck LN levels were fused with the primary image, then maximal radial displacement was measured at 1.5 cm intervals from skull base (SB) to caudal margin of LN level V, and the volume differences at each node level were quantified.

Results: The mean radial displacements were 2.26 (±1.03) mm in the control group and 3.05 (±1.97) in the H&N cancer patients. There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03). In addition, the mean radial displacement increased with the distance from SB. As for the mean volume differences, there was no statistical significance between the two groups.

Conclusion: This study suggests that a more generous radial margin should be applied to the lower part of the neck LN for better clinical target coverage and dose delivery.

No MeSH data available.


Related in: MedlinePlus

(A) Mean radial displacement in patients and control group (from skull base to neck lymph node (LN) level V inferior margin at 1.5 cm interval), (B) group mean radial displacement from skull base to level V; Spearman's rho correlation coefficient = 0.638 , p < 0.001.
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Figure 4: (A) Mean radial displacement in patients and control group (from skull base to neck lymph node (LN) level V inferior margin at 1.5 cm interval), (B) group mean radial displacement from skull base to level V; Spearman's rho correlation coefficient = 0.638 , p < 0.001.

Mentions: The tendency of radial displacement increased with the distance from SB to LN level V inferior margin (Fig. 4A). The maximal radial displacement occurred at 10.5 cm from SB in both groups. Each group's mean radial displacement is shown in Table 2. The correlation between the distance from SB and radial displacement was evaluated with Spearman's rho correlation coefficient. The correlation coefficient was 0.638 and statistically significant (p < 0.001) (Fig. 4B). The patient group had a greater radial displacement than control group in each measured point. In addition, mean radial displacement was also evaluated according to each group and the values at 6-cm and 10.5-cm distances from SB showed statistical significance (p = 0.011 and p = 0.005, respectively). As for the total mean displacement, the patient group had a greater radial displacement (3.05 ± 1.97 cm) than the normal control group (2.26 ± 1.03 cm), and their difference was also showed statistical significance (p = 0.03).


Radial displacement of clinical target volume in node negative head and neck cancer.

Jeon W, Wu HG, Song SH, Kim JI - Radiat Oncol J (2012)

(A) Mean radial displacement in patients and control group (from skull base to neck lymph node (LN) level V inferior margin at 1.5 cm interval), (B) group mean radial displacement from skull base to level V; Spearman's rho correlation coefficient = 0.638 , p < 0.001.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3475961&req=5

Figure 4: (A) Mean radial displacement in patients and control group (from skull base to neck lymph node (LN) level V inferior margin at 1.5 cm interval), (B) group mean radial displacement from skull base to level V; Spearman's rho correlation coefficient = 0.638 , p < 0.001.
Mentions: The tendency of radial displacement increased with the distance from SB to LN level V inferior margin (Fig. 4A). The maximal radial displacement occurred at 10.5 cm from SB in both groups. Each group's mean radial displacement is shown in Table 2. The correlation between the distance from SB and radial displacement was evaluated with Spearman's rho correlation coefficient. The correlation coefficient was 0.638 and statistically significant (p < 0.001) (Fig. 4B). The patient group had a greater radial displacement than control group in each measured point. In addition, mean radial displacement was also evaluated according to each group and the values at 6-cm and 10.5-cm distances from SB showed statistical significance (p = 0.011 and p = 0.005, respectively). As for the total mean displacement, the patient group had a greater radial displacement (3.05 ± 1.97 cm) than the normal control group (2.26 ± 1.03 cm), and their difference was also showed statistical significance (p = 0.03).

Bottom Line: We use the second cervical vertebra body as a reference point to match each CT image set.There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03).In addition, the mean radial displacement increased with the distance from SB.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea.

ABSTRACT

Purpose: To evaluate the radial displacement of clinical target volume in the patients with node negative head and neck (H&N) cancer and to quantify the relative positional changes compared to that of normal healthy volunteers.

Materials and methods: Three node-negative H&N cancer patients and five healthy volunteers were enrolled in this study. For setup accuracy, neck thermoplastic masks and laser alignment were used in each of the acquired computed tomography (CT) images. Both groups had total three sequential CT images in every two weeks. The lymph node (LN) level of the neck was delineated based on the Radiation Therapy Oncology Group (RTOG) consensus guideline by one physician. We use the second cervical vertebra body as a reference point to match each CT image set. Each of the sequential CT images and delineated neck LN levels were fused with the primary image, then maximal radial displacement was measured at 1.5 cm intervals from skull base (SB) to caudal margin of LN level V, and the volume differences at each node level were quantified.

Results: The mean radial displacements were 2.26 (±1.03) mm in the control group and 3.05 (±1.97) in the H&N cancer patients. There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03). In addition, the mean radial displacement increased with the distance from SB. As for the mean volume differences, there was no statistical significance between the two groups.

Conclusion: This study suggests that a more generous radial margin should be applied to the lower part of the neck LN for better clinical target coverage and dose delivery.

No MeSH data available.


Related in: MedlinePlus