March 2016, Vol. 5, No. 2
Reirradiation of Pelvic Area Is Safe and Improves Quality of Life
Experience at a high-volume center suggests that reirradiation of the pelvis for cancer recurrence or second genitourinary (GU) malignancy is safe in patients with advanced cancer and can achieve excellent and durable palliation of symptoms without causing severe radiation-induced morbidity. These patients are typically near the end of life, and palliation of their symptoms improves the quality of their remaining time.
Reirradiation of the GU area is controversial, with no existing guidelines, explained lead author Sophia C. Kamran, MD, a radiologist at Dana-Farber Cancer Institute in Boston, MA.
“Patients with genitourinary malignancies commonly receive radiation. Many may develop a recurrence or a secondary neoplasm. There is resistance in the cancer community to reirradiation of the pelvis due to concerns about the risk of bowel and bladder toxicity. We showed that with careful and safe planning, we can safely reirradiate the pelvic area and eliminate toxicity,” Kamran said.
She reported experience in 28 patients with locally advanced symptomatic disease (27 males, 1 female) who were reirradiated. Patients had a variety of primary tumor types, including rectal, bladder, penile, prostate, ureteral, and large cell lymphoma. For their primary disease, they were treated with radiation alone (47%), chemotherapy plus radiation (7%), radiation plus surgery (32%), and all 3 modalities (14%).
Patients were treated with high-dose external beam pelvic reirradiation, defined as >50 Gy given with standard fractionation or hypofractionation bioequivalent to >50 Gy.
All patients had pain, bleeding, and/or bladder symptoms as indications for reirradiation. Effectiveness was scored according to reduction in these signs and symptoms. Treatment was carefully planned to increase precision and avoid critical normal organs using a variety of maneuvers depending on the case: 4-D simulation (n = 7), customized immobilization devices (n = 28), image-guided radiation delivery (n = 20), 3-D conformal therapy (n = 20), and 2-D therapy (n = 4).
Median overall survival was 5.8 months (range, 0.3-39 months). Death was secondary to systemic disease in all cases.
Excellent and durable palliation was observed following reirradiation. “Ninety-two percent of patients responded to reirradiation at high doses with resolution of their symptoms and limited toxicity,” she said.
No Radiation Therapy Oncology Group grade 3/4 treatment-related toxicity was reported.
“Most people assume this is not safe. We monitored patients’ symptoms weekly. Reirradiation provides great palliative therapy in patients with a recurrence of second cancer. They can enjoy good quality of life free of these symptoms near the end of life,” she stated.
“Meticulous treatment planning, with avoidance of sensitive structures, and short survival times may have contributed to the low morbidity we saw in this series. These results need to be validated in a prospective study with a larger number of patients,” Kamran concluded.
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