Case presentation
Our 18-month-old patient with recurrent oRT of the right side presented to our hospital with rapid tumor growth and profuse bleeding from the right orbital cavity. Magnetic Resonance Imaging (MRI) revealed extensive tumor recurrence in the orbit with infiltration of the adjacent bony structures of the maxillary sinus the nasal cavity, ethmoid cells, and frontal base, as well as intracranial extension via the right optic canal (Fig.1 A).
13 months prior to this presentation, he had undergone surgical resection of the tumor, chemotherapy according to the European Rhabdoid Registry (EU-RHAB) and proton radiotherapy of 54 Gray (Gy). One year later, the first local recurrence was observed and the patient underwent tumor resection followed by orbital exenteration.
A significant drop in hemoglobin level (75 g/l) was noted on admission, requiring transfusions of packed red blood cells. Considering the patient’s medical history and previous treatments, tumor location and skin toxicity in the right maxillary and periorbital regions after proton therapy, a combined approach consisting of transarterial embolization and subsequent BT was chosen to achieve hemostasis and local tumor control.
Due to the young age, the treatment was performed under general anesthesia. Diagnostic angiography showed a predominantly medial tumor blush via the nasal ethmoid branches and the infraorbital artery; therefore, these vessels were embolized with precipitating hydrophobic injectable liquid (PHIL) 25% after exclusion of collaterals, particularly to the internal carotid artery (ICA). (Fig.2 A).
One hour later, after CT marking for BT, a total of twelve plastic tubes and four Onco-Smarts catheters were implanted in the cheek, caudal and lateral to the orbital cavity, to completely cover the clinical target volume (CTV) (Fig 2.B,C,D and E). We applied a total dose of 28 Gy (7x 4Gy) over four days, 2 fractions per day with minimum intervals of 6 hours by using a 192Ir source taking into account the dose of the proton therapy completed 7 months earlier.
The first fraction was administered on the same day of embolization and implantation, and the remaining six sessions were conducted on the following days without complications.
Regular wound checks showed intact skin without development of macroscopic tumor progress and bleeding.
On 6-week follow up, MRI showed a significant decrease in the size of the tumor in the right orbit (Fig. 1B). Unfortunately, the patient died 2 months after the procedure due to new distant metastases.