Brachial Plexopathy After Single-Fraction Stereotactic Body Radiation Therapy in Apical Lung Tumors

Advanced navigation technology enables endobronchial brachytherapy for peripheral lung cancer: An old technique plays a new role

PURPOSE

To investigate the feasibility of super-selectively endobronchial brachytherapy in the treatment of peripheral lung cancer guided by advanced navigation technology.

METHODS AND MATERIALS

Six patients with peripheral lung tumors successfully underwent treatment with super-selectively endobronchial brachytherapy guided by advanced navigation technology following pathway planning and were subsequently followed up to assess survival and treatment-related toxicities.

RESULTS

The endobronchial applicators were successfully placed inside the tumors of all patients using advanced navigation techniques according to the pretreatment plan, and brachytherapy was delivered at curative doses after evaluation using radiotherapy planning software. None of the patients showed local progression of the treated lesions during the follow-up for a duration ranging from 11 months to 35 months, with a median follow-up time of 23 months. The patient with the longest follow-up, nearly 3 years, exhibited a stable condition. After undergoing endobronchial brachytherapy, patients predominantly experienced localized fibrosis as indicated. No significant alterations in cardiopulmonary function were detected during the follow-up, and no other adverse effects were found.

CONCLUSIONS

The use of endobronchial brachytherapy for the curative treatment of peripheral lung cancers is feasible. Furthermore, the development of novel bronchial navigation techniques has the potential to broaden the application of endobronchial brachytherapy.

Dosimetric analysis of brachial plexopathy after stereotactic body radiotherapy: Significance of organ delineation

OBJECTIVES

Examine the significance of contouring the brachial plexus (BP) for toxicity estimation and select metrics for predicting radiation-induced brachial plexopathy (RIBP) after stereotactic body radiotherapy.

MATERIALS AND METHODS

Patients with planning target volume (PTV) ≤ 2 cm from the BP were eligible. The BP was contoured primarily according to the RTOG 1106 atlas, while subclavian-axillary veins (SAV) were contoured according to RTOG 0236. Apical PTVs were classified as anterior (PTV-A) or posterior (PTV-B) PTVs. Variables predicting grade 2 or higher RIBP (RIBP2) were selected through least absolute shrinkage and selection operator regression and logistic regression.

RESULTS

Among 137 patients with 140 BPs (median follow-up, 32.1 months), 11 experienced RIBP2. For patients with RIBP2, the maximum physical dose to the BP (BP-Dmax) was 46.5 Gy (median; range, 35.7 to 60.7 Gy). Of these patients, 54.5 % (6/11) satisfied the RTOG limits when using SAV delineation; among them, 83.3 % (5/6) had PTV-B. For patients with PTV-B, the maximum physical dose to SAV (SAV-Dmax) was 11.2 Gy (median) lower than BP-Dmax. Maximum and 0.3 cc biologically effective doses to the BP based on the linear-quadratic-linear model (BP-BEDmax LQL and BP-BED0.3cc LQL, α/β = 3) were selected as predictive variables with thresholds of 118 and 73 Gy, respectively.

CONCLUSION

Contouring SAV may significantly underestimate the RIBP2 risk in dosimetry, especially for patients with PTV-B. BP contouring indicated BP-BED0.3cc LQL and BP-BEDmax LQL as potential predictors of RIBP2.