Proposal for the delineation of the nodal CTV in the node-positive and the post-operative neck

doi:10.1016/j.radonc.2006.03.009

Radiotherapy and Oncology

Volume 79, Issue 1, April 2006, Pages 15-20

https://doi.org/10.1016/j.radonc.2006.03.009 Get rights and content

Abstract

Background and purpose

In 2003, a panel of experts published a set of consensus guidelines regarding the delineation of the neck node levels (Radiother Oncol, 2003; 69: 227–36). These recommendations were applicable for the node-negative and the N1-neck, but were found too restrictive for the node-positive and the post-operative neck.

Patients and methods

In this framework, using the previous recommendations as a backbone, new guidelines have been proposed taking into account the specificities of the node-positive and the post-operative neck.

Results

Inclusion of the retrostyloid space cranially and the supra-clavicular fossa caudally is proposed in case of neck nodes (defined radiologically or on the surgical specimen) located in levels II, and IV or Vb, respectively. When extra-capsular rupture is suspected (on imaging) or demonstrated on the pathological specimen, adjacent muscles should also be included in the CTV. For node(s) located at the boundary between contiguous levels (e.g. levels II and Ib), these two levels should be delineated. In the post-operative setting, the entire ‘surgical bed’ should be included. Last, the retropharyngeal space should be delineated in case of positive neck from pharyngeal tumors.

Conclusions

The objective of the manuscript is to give a comprehensive description of the new set of guidelines for CTV delineation in the node-positive neck and the post-operative neck, with a complementary atlas of the new anatomical structures to be included.

Section snippets

Evidences for the need of specific guidelines in the node-positive and in the post-operative neck

A legitimate concern when selecting and delineating the target volumes in preparation of 3D-CRT or IMRT for head and neck squamous cell carcinoma (HNSCC) is that too tight target volumes might lead to unacceptable rate of marginal failures. For the node-negative neck, the proposed guidelines have reached a worldwide consensus [5]. For the node-positive neck, few data indicate that indeed the CTV might have to be extended in specific cases, which are detailed below.

There are not that many

Guidelines for CTV selection and delineation in the node-positive neck

Based on the few data summarized in Section 2, recommendations can be proposed for the delineation of the nodal CTV in the node-positive neck. Because head and neck IMRT is still in its infancy, it seems appropriate to be generous in target volume delineation until more data are available on the pattern of recurrence after selective treatment. The following recommendations are based on the consensus guidelines already published for the delineation of the CTV in the N0 neck, which remain the

Recommendations for CTV selection and delineation in the post-operative neck

In the post-operative situation, there are even fewer data on which one could build specific recommendations for CTV delineation. It should be understood that the indications for post-operative irradiation on the one hand, and the selection—and consequently the delineation—of the CTV in the post-operative setting on the other hand should follow institutional guidelines jointly established by head and neck surgeons and radiation oncologists to guarantee treatment consistency and avoid over—or

Conclusions

Adequate selection and delineation of target volumes is a prerequisite for successful IMRT and 3D-CRT. The proposed guidelines intended to extend the existing recommendations for the node-negative neck to the node-positive and the post-operative neck. Such new guidelines were based more on logical assumptions than on definitive data, which are unfortunately still lacking. Interestingly, application of these guidelines somehow matches the field size that one was used to draw (i.e. from the

Acknowledgements

The authors wish to express their gratitude to Prof. B. Lengele for helpful discussion on the anatomic terminology.

References (19)

K.S. Chao et al.
Patterns of failure in patients receiving definitive and postoperative IMRT for head-and-neck cancer
Int J Radiat Oncol Biol Phys
(2003)
L.A. Dawson et al.
Patterns of local–regional recurrence following parotid-sparing conformal and segmental intensity-modulated radiotherapy for head and neck cancer
Int J Radiat Oncol Biol Phys
(2000)
A. Eisbruch et al.
Intensity-modulated radiation therapy for head and neck cancer: emphasis on the selection and delineation of the targets
Semin Radiat Oncol
(2002)
V. Gregoire et al.
Selection and delineation of lymph node target volumes in head and neck conformal radiotherapy. Proposal for standardizing terminology and procedure based on the surgical experience
Radiother Oncol
(2000)
V. Grégoire et al.
CT-based delineation of lymph node levels and related CTVs in the node-negative neck: DAHANCA, EORTC, GORTEC, NCIC,RTOG consensus guidelines
Radiother Oncol
(2003)
P.J. Nowak et al.
A three-dimensional CT-based target definition for elective irradiation of the neck
Int J Radiat Oncol Biol Phys
(1999)
O.B. Wijers et al.
A simplified CT-based definition of the lymph node levels in the node negative neck
Radiother Oncol
(1999)
A. Eisbruch et al.
Recurrences near base of skull after IMRT for head-and-neck cancer: implications for target delineation in high neck and for parotid gland sparing
Int J Radiat Oncol Biol Phys
(2004)
K.S. Chao et al.
Determination and delineation of nodal target volumes for head-and-neck cancer based on patterns of failure in patients receiving definitive and postoperative IMRT
Int J Radiat Oncol Biol Phys
(2002)

There are more references available in the full text version of this article.

Cited by (315)

Proposals for the delineation of neck clinical target volume for definitive Radiation therapy in patients with oral/ oropharyngeal squamous cell cancer based on lymph node distribution
2024, Radiotherapy and Oncology
To establish the distribution pattern of cervical lymph node metastasis (LNM) and propose optimized clinical target volume (CTV) boundaries specific to oral/ oropharyngeal squamous cell cancer (OSCC/OPSCC).
531 patients with pathologically confirmed OSCC/OPSCC were enrolled from January 2013 to June 2022. Patients were stratified into two groups based on the minimal distance from the lesion's edge to the body's midline: ≤1 cm or > 1 cm. The geometric center of cervical metastatic LN was marked on a template CT. LN distribution probability maps were established. The relationships between the LN distribution and consensus guidelines were analyzed to propose modifications for CTV boundaries specific to OSCC/OPSCC.
A total of 1962 positive LNs were enrolled. Compared with the > 1 cm group, the ≤ 1 cm group has following feature tendencies: male smokers, younger, median organs, large gross lesion, infiltrative growth pattern, contralateral LNM. The most frequently involved level of LNM was ipsilateral II, but ipsilateral Ib had the highest involvement rate in the > 1 cm OSCC group. In addition, tongue cancer had a higher incidence of LN extranodal extension (ENE), which mainly distributes in ipsilateral level II. The skip metastasis was prone to from level III to Vb (3.5 %) in LN(+)/ENE (-), and level Ib to VIa (3.7 %) in LN(+)/ENE (+). Accordingly, we proposed the following modifications: 1. only including lateral and posterior margin of submandibular gland within 5 mm; 2. retracting posterior boundary of level II to front edge of levator scapula muscle, and descending the upper boundary to transverse process of C2 vertebra only for OSCC; 3. including posterior third of thyroglossal muscle or anterior edge of sternocleidomastoid muscle; 4. sparing level Va in case of only level II involvement; 5. including upper area of the thyroid cartilage plate in case of level Ib LN(+)/ENE (+); 6. sparing level VIIa is considered.
This is the first description of LN topographic spread patterns for OSCC/OPSCC. Modified CTV for prophylactic irradiation was proposed to spare the organs at risk and minimize adverse effects.
Selectively sparing of the supraclavicular area during intensity-modulated radiotherapy in nasopharyngeal carcinoma: A double-center observation study
2024, Radiotherapy and Oncology
This study was aimed at evaluating the feasibility of sparing the supraclavicular area, namely levels IVb and Vc, during intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma (NPC) patients with N1-2 disease[except N1 disease with purely restropharyngeal lymph nodes(RPN) involvement], and providing a basis for the revision of International Guideline for the delineation of the clinical target volume (CTV).
Patients with NPC (stage T_anyN_1-2M₀) diagnosed pathologically in Fujian Cancer Hospital (Center 1, Only Lin SJ‘s attending group) from January 2014 to March 2018 and Jiangxi Cancer Hospital(Center 2) from January 2014 to December 2015 were included. According to our principle, the supraclavicular area (levels IVb and Vc) were excluded from the CTVnd. Survival outcomes focused on regional recurrence-free survival (RRFS) and recurrence rates of levels IVb and Vc were analysed.
A total of 672 eligible patients were recruited (Center 1, n = 362; Center 2, n = 310). There was no significant difference in 5-year RRFS (97.33 % vs. 97.24 %, p = 0.980), overall survival (OS) (89.14 % vs. 88.56 %, p = 0.327), local recurrence-free survival (LRFS) (94.90 % vs. 95.30 %, p = 0.593) and distant metastasis-free survival (DMFS) (89.38 % vs. 86.60 %, p = 0.130) between Center 1 and Center 2. Twenty patients developed regional failure (median: 36 months), among them, only one case (0.15 %) was recorded as levels IVb and Vc recurrence.
Omitting the supraclavicular area (levels IVb and Vc) during IMRT should be safe and feasible for N1-2 disease (except N1 disease with purely RPN involvement). Well-designed multicenter prospective trials should be conducted to confirm our findings.
Is bilateral radiotherapy necessary for patients with unilateral squamous cell carcinoma of unknown primary of the head and neck region?
2024, Clinical and Translational Radiation Oncology
Squamous cell carcinoma of unknown primary (SCC-CUP) of the head and neck region remains a clinical challenge, with uncertainty surrounding the necessity of contralateral irradiation of cervical lymphatic drainage in cases of unilateral involvement.
A retrospective study was conducted at the Department of Radiation Oncology, University Medical Center Mainz, on a cohort of 50 patients with unilateral SCC-CUP of the head and neck region treated between 2005 and 2019. 30 patients received bilateral and 20 received unilateral cervical radiotherapy. The majority (n = 38, 76 %) were treated with modern IMRT/ VMAT (Intensity-modulated Radiation Therapy/ Volumetric Modulated Arc Therapy) techniques.
After a median follow-up of 64.5 months, locoregional recurrences occurred in 26 % of cases (n = 13/50), all of which were ipsilateral and predominantly within the volume of the previous irradiated CTV (clinical target volume) (85 %, n = 11/13). No patient treated unilaterally developed a contralateral recurrence in the neck. After 3 years, we observed 7 locoregional recurrences in the bilateral irradiated group (n = 7/30, 23 %), and 5 locoregional recurrences in the unilateral irradiated group (n = 5/20, 25 %). After 3 years, 12 patients had died in the bilateral irradiated group (n = 12/30, 40 %), and 7 in the unilateral irradiated group (n = 7/20, 35 %). 7 Patients showed distant metastases after 3 years in the bilateral irradiated group (n = 7/30, 23 %), and 2 in the unilateral irradiated group (n = 2/20, 10 %). Locoregional control (LRC) at 5 years was 66.2 % in the bilaterally irradiated group, and 70.0 % in the unilaterally irradiated group. Overall survival (OS) was 52.6 % (bilateral) and 64.0 % (unilateral). Distant metastasis-free survival (DMFS) was 74.7 % (bilateral) and 84.4 % (unilateral). No significant differences were observed in OS (p = 0.37), LRC (p = 0.91), and DMFS (p = 0.91) between the groups.
Acute toxicity ≥ °2 accordingly CTCAE (Common Terminology Criteria of Adverse Events) was high with 97% while late toxicity ≥ °2 was moderate with 31%. There was no statistically significant difference between the group of unilateral and bilateral irradiated patients.
These data suggest that contralateral cervical irradiation may be of limited benefit in patients with SCC-CUP, as recurrences occured ipsilaterally, and predominantly within the area of prior irradiation. Unilateral irradiation seems to be adequate for carefully selected patients.
Significance of radiologic extranodal extension in locoregionally advanced nasopharyngeal carcinoma with lymph node metastasis: a comprehensive nomogram
2024, Brazilian Journal of Otorhinolaryngology
We aimed to assess the significance of rENE and creat a predictive tool (nomogram) for estimating Overall Survival (OS) in locoregionally advanced Nasopharyngeal Carcinoma (NPC) patients with Lymph Node Metastasis (LNM) based on their clinical characteristics and Radiologic Extranodal Extension (rENE).
Five hundred and sixty-nine NPC patients with LNM were randomly divided into training and validation groups. Significant factors were identified using univariate and multivariate analyses in the training cohort. Then, the nomogram based on the screening results was established to predict the Overall Survival (OS). Calibration curves and the Concordance index (C-index) gauged predictive accuracy and discrimination. Receiver Operating Characteristic (ROC) analysis assessed risk stratification, and clinical utility was measured using Decision Curve Analysis (DCA). The nomogram's performance was validated for discrimination and calibration in an independent validation cohort.
A total of 360 (63.2%) patients were present with radiologic extranodal extension at initial diagnosis. Patients with rENE had significantly lower OS than other patients. Multivariate analysis identified the five factors, including rENE, for the nomogram model. The C-index was 0.75 (0.71–0.78) in the training cohort and 0.76 (0.69–0.83) in the validation cohort. Notably, the nomogram outperformed the 8th TNM staging system, as evident from the higher AUC values (0.77 vs. 0.60 for 2 year and 0.75 vs. 0.65 for 3 year) and well-calibrated calibration curves. Decision curve analysis indicated improved Net Benefit (NB) with the nomogram for predicting OS. The log-rank test confirmed significant survival distinctions between risk groups in both training and validation cohorts.
We demonstrated the prognostic value of rENE in nasopharyngeal carcinoma and developed a nomogram based on rENE and other factors to provide individual prediction of OS for locoregionally advanced nasopharyngeal carcinoma with lymph node metastasis.
III.
Evaluation of different algorithms for automatic segmentation of head-and-neck lymph nodes on CT images
2023, Radiotherapy and Oncology
To investigate the performance of 4 atlas-based (multi-ABAS) and 2 deep learning (DL) solutions for head-and-neck (HN) elective nodes (CTVn) automatic segmentation (AS) on CT images.
Bilateral CTVn levels of 69 HN cancer patients were delineated on contrast-enhanced planning CT. Ten and 49 patients were used for atlas library and for training a mono-centric DL model, respectively. The remaining 20 patients were used for testing. Additionally, three commercial multi-ABAS methods and one commercial multi-centric DL solution were investigated. Quantitative evaluation was assessed using volumetric Dice Similarity Coefficient (DSC) and 95-percentile Hausdorff distance (HD_95%). Blind evaluation was performed for 3 solutions by 4 physicians. One recorded the time needed for manual corrections. A dosimetric study was finally conducted using automated planning.
Overall DL solutions had better DSC and HD_95% results than multi-ABAS methods. No statistically significant difference was found between the 2 DL solutions. However, the contours provided by multi-centric DL solution were preferred by all physicians and were also faster to correct (1.1 min vs 4.17 min, on average). Manual corrections for multi-ABAS contours took on average 6.52 min Overall, decreased contour accuracy was observed from CTVn2 to CTVn3 and to CTVn4. Using the AS contours in treatment planning resulted in underdosage of the elective target volume.
Among all methods, the multi-centric DL method showed the highest delineation accuracy and was better rated by experts. Manual corrections remain necessary to avoid elective target underdosage. Finally, AS contours help reducing the workload of manual delineation task.
Basic concepts and directions in the radiation therapy quality assurance processes of clinical trials
2023, Cancer/Radiotherapie
The radiation therapy quality assurance of clinical trials is internationally recognized as a key factor to control the quality of radiotherapy for its impact on clinical trial's goals. Quality assessment may be performed at different levels and by different means, which are now quite standardized. The optimal radiation therapy quality assurance of clinical trials trade-off to maintain accrual rates, radiotherapy quality and optimize clinical trial research processes is yet to be defined. This article addresses current definitions, processes, limitations and directions.
Le processus d’assurance qualité des essais cliniques en radiothérapie est internationalement reconnu comme un facteur clé pour contrôler la qualité de la radiothérapie et contrôler l’impact de la qualité de la radiothérapie sur les objectifs des essais cliniques. L’évaluation de la qualité peut être effectuée à différents niveaux et par différents moyens, qui sont désormais assez standardisés. Le compromis optimal entre le choix des procédures d’évaluation de la qualité (questionnaires de faisabilité, accréditation des centres avant inclusions, assurance qualité des patients de l’essai) de la radiothérapie et le maintien de la dynamique d’inclusions reste à définir. Cet article aborde les définitions, les processus, les limites et les orientations actuelles.

View all citing articles on Scopus

View full text

Target volume delineationProposal for the delineation of the nodal CTV in the node-positive and the post-operative neck

Abstract

Background and purpose

Patients and methods

Results

Conclusions

Section snippets

Evidences for the need of specific guidelines in the node-positive and in the post-operative neck

Guidelines for CTV selection and delineation in the node-positive neck

Recommendations for CTV selection and delineation in the post-operative neck

Conclusions

Acknowledgements

Int J Radiat Oncol Biol Phys

Int J Radiat Oncol Biol Phys

Semin Radiat Oncol

Radiother Oncol

Radiother Oncol

Int J Radiat Oncol Biol Phys

Radiother Oncol

Int J Radiat Oncol Biol Phys

Int J Radiat Oncol Biol Phys

Target volume delineation
Proposal for the delineation of the nodal CTV in the node-positive and the post-operative neck