Dose distribution and shrinkage of acoustic neurinomas 2 years after Gamma Knife treatment

Outcomes of 75 patients over 12 years treated for acoustic neuromas with linear accelerator-based radiosurgery

The aim of this study was to investigate the efficacy of linear accelerator (LINAC)-based radiosurgery in the treatment of acoustic neuromas. In this retrospective study, we enrolled 75 patients with non-neurofibromatosis type 2 acoustic neuromas who were followed-up for more than 5years. The 75 patients were divided into 3 groups: patients with a newly diagnosed tumor; those with a residual tumor; and those with a recurrent tumor. The average follow-up period was 97.8months. The overall tumor progression-free rate was 92%, and corresponding rates among those with newly diagnosed tumors was 100%, residual tumors was 84.4%, and recurrent tumors was 92.8% (p=0.028). Lesion localization using CT scans correlated with a higher tendency for tumor progression than lesion localization using CT-MRI fusion images (15.6% versus 2.4%, respectively). Residual tumors treated with radiosurgery have a higher progression rate, and careful lesion localization using CT-MRI image fusion is required.

Tumor diameter/volume and pelvic node status assessed by magnetic resonance imaging (MRI) for uterine cervical cancer treated with irradiation

PURPOSE

To evaluate the prognostic value of tumor diameter/volume and pelvic node status assessed by magnetic resonance imaging (MRI) in patients with uterine cervical cancer treated with radiation therapy.

METHODS AND MATERIALS

Forty-four patients with intact uterine cervical squamous carcinoma treated with a combination of external irradiation and high-dose-rate intracavitary therapy were analyzed. Actuarial disease-free survival (DFS), pelvic control rate (PC), and distant metastasis-free rate (DMF) were analyzed by tumor diameter, volume, and pelvic node status assessed by pretreatment MRI.

RESULTS

Anteroposterior (AP) and lateral (RL) tumor diameter significantly affected DFS. The 2-year DFS was 74% for patients with < 40 mm in AP diameter tumor, and 24% for > or = 40 mm tumor (p = 0.02). Whereas PC was not influenced, DMF was significantly affected by AP tumor diameter. Tumor volume did not significantly affect any endpoints. Patients with enlarged pelvic nodes had significantly poorer outcome compared to those with none on PC, DMF, and DFS. The 2-year DFS was 78% for node-negative, and 10% for node-positive patients (p = 0.0001).

CONCLUSION

AP tumor diameter and pelvic lymph node status assessed by MRI were the significant prognostic factors in uterine cervical cancer treated with irradiation. Prognostic value of tumor volume should be reassessed prospectively with an appropriate imaging technique. AP tumor diameter predominantly affected the incidence of distant metastasis, and lymph node status affected both pelvic control and distant metastasis.