Abstract

Objectives: The management of large and unresectable tumors remains a significant challenge in the palliative setting. Our objective is to report the results of a short course of Lattice Radiotherapy (LRT) for the treatment of three patients with advanced, voluminous, inoperable primary sarcomas of the lung.

Methods: Three patients with ages of 65, 82, and 88 years old presenting with tumor volumes of 310 cc, 333 cc, and 680 cc, respectively, were treated with palliative intent using Lattice Radiation Therapy (LRT SBRT). All patients received five fractions of 12 Gy per fraction to the lattice vertices totaling 60 Gy and 5 Gy per fraction to the tumor periphery for a total of 25 Gy, respectively, using VMAT based LRT. All three patients had comorbid diseases and were poor surgical candidates.

Results: At completion of treatment all three patients experienced a tumor reduction found to be 11 %, 42%, and 48%, respectively. Symptomatic relief was observed in all three. There was no significant toxicity encountered. The imaging follow-up time was 17, 13, and 14 months respectively. As per RECIST, one patient had stable disease, one partial response, and the other one had a complete response. Two patients died 18 and 27 months after the treatment, respectively. The third patient is still alive at the time of this writing, 32 months post treatment.

Conclusion(s): Lattice Radiotherapy is an effective palliative treatment for patients with large sarcomas of the lung. All three patients had marked symptomatic improvement and tumor response as well as a significant increase in overall survival. This technique could also be used pre-operatively to render once inoperable patients into surgical candidates.