Robotic stereotactic ablative radiotherapy for renal cell carcinoma in patients with impaired renal function.

BACKGROUND: Robotic stereotactic ablative radiotherapy (SABR) is currently under investigation as a noninvasive treatment option for patients with renal cell carcinoma (RCC). For radiation therapy of RCC, tumor motion and the need for high ablative doses while preserving the remaining renal parenchyma is a challenge. We aimed to analyze the safety and efficacy of robotic radiosurgery in RCC in a specific difficult subgroup of patients with impaired renal function. METHODS: We retrospectively identified all patients with RCC, treated with robotic SABR and motion compensation in our institution between 2012 and 2017. Either single fraction SABR of 24 or 25 Gy or 3 fractions of 12 Gy prescribed to the 70% isodose line was applied. Local control, overall survival, radiation side effects were evaluated together with renal function and tumor motion. RESULTS: We analyzed data of 13 lesions treated in 10 patients with clear cell RCC and a mean age of 70.5 ± 13.6 years (range: 48-87). Prior to SABR, 8 patients underwent previous complete and/or partial nephrectomy, 7 patients presented with chronic kidney disease ≥ stage 3. The median of minimum, mean and maximum planning target volume doses were 23.2, 29.5 and 35.0 Gy for single fraction and 24.4, 42.5 and 51.4 Gy for the three fractions regime. Persistent local control by robotic SABR was achieved in 9 out of 10 patients (92.3% of all lesions) within a median follow-up period of 27 month (range: 15-54). One patient underwent nephrectomy due to progressive disease and sufficient renal function of the contralateral kidney. Renal function remained stable with a mean estimated glomerular filtration rate (eGFR) of 51.3 ± 19.7 ml/min at baseline and 51.6 ± 25.8 ml/min at follow-up. The largest respiratory-induced tumor motion was seen in superior-inferior direction, compensated by the CyberKnife with mean targeting errors of maximal 2.2 mm. CONCLUSIONS: Robotic SABR is technically feasible for the treatment of RCC in preexisting kidney disease with good local tumor control at about 2 years follow-up. Robotic SABR with motion tracking offers a valid treatment option for patients, who are at increased risk for progression to end-stage renal disease due to partial nephrectomy or ablative techniques.

CyberKnife radiosurgery for the treatment of orbital metastases.

Purpose of this study is to evaluate radiographic therapy response, clinical outcome and adverse effects of CyberKnife radiosurgery in patients suffering from orbital metastases. Sixteen orbital metastases originating from different solid cancers in fourteen patients were treated by single fraction CyberKnife radiosurgery. Radiographic response and clinical outcome were evaluated. The treated tumor volume ranged from 0.2 to 35 cm3 (median 2.3 cm3, mean 7.0 cm3, SD 6 10.4 cm3, CI 0.9-9.4 cm3). The prescription dose ranged from 16.5-21 Gy (median 18 Gy, mean 18.2 Gy, SD 6 1.2 Gy, CI 17.0-18.4 Gy). A no change situation was observed in nine lesions, partial remission in four as well as complete remission in one metastasis. Tumor growth was stabilized or regressive following CyberKnife therapy in 87% of the cases. Recurrence was observed in two cases (13%). Before therapy, three patients suffered from visual disturbance and five patients reported diplopia. Six patients had no initial symptoms. After therapy, one patient indicated improvement of the present visual deficit and two patients no change. Out of the two patients with persistent diplopia, two reported improvement after therapy and three no change. No progression of symptoms was noted in any of the cases. Fourteen out of sixteen treated lesions were stable or regressive following CyberKnife radiosurgery (87%). As no serious adverse effects were reported in this series, CyberKnife therapy was shown to be of great value for local management of orbital metastases.

Radiosurgery of spinal meningiomas and schwannomas.

Purpose of this study is to analyze local control, clinical symptoms and toxicity after image-guided radiosurgery of spinal meningiomas and schwannomas. Standard treatment of benign spinal lesions is microsurgical resection. While a few publications have reported about radiosurgery for benign spinal lesions, this is the first study analyzing the outcome of robotic radiosurgery for benign spinal tumors, treated exclusively with a non-invasive, fiducial free, single-fraction setup. Thirty-six patients with spinal meningiomas or schwannomas were treated, utilizing a robotic radiosurgery system (CyberKnife®, Accuray Inc. Sunnyvale CA), and were followed prospectively. Medical history, histology, clinical symptoms and radiographic outcome were recorded. Thirty-nine spinal lesions were treated because of tumor recurrence, remnants after microsurgery, multiple lesions, or rejection of open surgery. Median age was 45 years (range 18-80 years). Median target volume was 3.4 cm(3) (range 0.2-43.4 cm(3)). Histology revealed 28 schwannomas and 11 meningiomas (WHO grade I). All spinal levels were affected. Median prescription dose was 14 Gray (95% C.I. 13.4-14 Gy) to the 70% isodose. After a median follow-up of 18 months (range 6-50 months) no local tumor progression was detected. 20 lesions (51%) remained stable, 19 tumors (49%) decreased in size. One patient with schwannomatosis was treated repeatedly for three new tumor locations. Pain was the initial symptom in 16 of 25 schwannoma patients, and in 3 of 11 patients with meningiomas. Pain levels decreased in 8/19 patients. All but one patient with motor deficits remained clinically stable. No myelopathic signs where found. Single-session radiosurgery for benign spinal tumors in selected patients has proven to inhibit tumor progression within the observed period without signs of early toxicity. Radiosurgery offers an additional treatment option, if microsurgery is not feasible in cases of tumor recurrence, post-resection remnants, multiple lesions, or medical comorbidity.

Frameless single-session robotic radiosurgery of liver metastases in colorectal cancer patients.

INTRODUCTION: Due to advanced chemotherapy regimens, patients presenting with residual liver metastases of colorectal cancer (CRC) has increased. Surgery of residual metastases enhances overall survival, but surgical resection is often limited. Less invasive techniques have been invented to enhance local disease control. We investigated in a selected patient cohort local control of liver metastasis from CRC using robotic radiosurgery. METHODS AND MATERIALS: In this study patients with colorectal liver metastases were prospectively followed after having been treated with single-session radiosurgery using a robotic image-guided device and real-time tumour tracking. The primary end-point was local control (LC); secondary end-points were toxicity, progression-free survival (PFS) and overall survival (OS). Extrahepatic metastases were excluded using a whole body (PET-CT: positron emission tomography computed tomography). Follow up was done by liver MRI every 3 months post-treatment. RESULTS: Fourteen patients (median age 65 years), with a total of 19 colorectal liver metastases were treated with 24 Gy in one fraction. Median follow up was 16.8 months. A one-year LC rate of 87% and a median PFS of 9.2 months were reached. DISCUSSION: Frameless robotic image-guided radiosurgery with real-time tumour tracking as an effective treatment for patients with colorectal liver metastases. This technique enhances the possibilities of multidisciplinary oncological concepts.

[Collision tumor of a hypopharyngeal adenoidcystic carcinoma and a laryngeal squamous cell carcinoma]. / Kollisionstumor eines adenoidzystischen Karzinoms des Hypopharynx und eines Plattenepithelkarzinoms des Larynx.

INTRODUCTION: Malignancies in head and neck cancer are mainly squamous cell carcinomas. Adenoid cystic carcinomas are rare lesions of this site. Laryngeal adenoid cystic carcinoma is estimated to occur in 0.1 - 0.7 % of all laryngeal carcinomas. Adenoid cystic carcinomas are rarely located in the hypopharynx. To our knowledge there is no case report of adenoid cystic carcinoma of the hypopharynx as part of a collision tumor of the larynx. CASE REPORT: A 47-year-old male patient was diagnosed with an adenoid cystic carcinoma of the hypopharynx and a squamous cell carcinoma of the larynx. Because of local extension of both tumors laryngectomy and partial pharyngotomy with bilateral neck dissection was performed followed by radiation therapy. Clinical aspects as well as histomorphological and immunohistochemical criteria of both tumor entities are discussed. DISCUSSION AND CONCLUSIONS: Immunohistochemical characteristics showed two different carcinoma entities in the larynx and hypopharynx. Only by complete histological investigation of a carcinoma those rare cases of a collision tumor can be detected. Both tumor entities need to be considered for therapy strategy and oncological follow-up planning.