Combination Of Surgery And Stereotactic Radiation Therapy (Srt) With 3d-Spect/Ct Treatment Planning For Primary And Metastatic Liver Tumors

Evaluate the feasibility, safety, and efficacy of SRT in combination with hepatic resection of primary and metastatic liver tumors. Sixteen patients completed hepatectomy and SRT for either hepatocellular carcinoma (HCC) (6) or metastases from colorectal (5), neuroendocrine (2), uterine (2), or sarcoma (1) primary. Twenty-one operable metastases were resected in 5 patients and gold fiducials were placed into the unresectable lesions to facilitate definitive SRT. Three patients with initially unresectable tumors received preoperative SRT followed by R0 resection. SRT as a bridge to liver transplant was used in 4 patients with HCC. Four patients had salvage SRT for recurrence after surgery. All patients completed 4D-CT and 3D-SPECT/CT to define functional normal liver volume (NLV) for SRT planning. MV-fluoro was performed to confirm tumor/fiducial respiratory motion within the PTV. In retrospect, our patient's treatment planning, clinical, laboratory, and imaging data were reviewed under an IRB approved outcomes study. Toxicity was graded according to CTCAE v3.0. All patients successfully completed a combination of hepatectomy and SRT. Forty lesions were treated with hepatectomy and 20 (≤ 3 per patient) received SRT with a mean PTV of 132.6 cc (range, - 9.7-803.5). The mean dose was 47.7 Gy (range, - 36-60) prescribed to the PTV in 5-16 fractions. With median follow-up of 17.7 months (range, - 5.8-32.1), 2 patients had grade 3 elevation of Total Bilirubin prior to initiation of SRT which persisted through treatment. No incidence of > grade 1 radiation-induced liver disease was observed. The most common clinical toxicity was Grade ≤ 2 fatigue. No patients had grade > 2 clinical toxicity. As a group, functional NLVs defined on 3D-SPECT/CT were significantly reduced compared to liver volumes defined on CT and estimated from the Body Surface Area equation (p = 0.037 and p = 0.0012 respectively). Postoperative morbidity was ≤ Grade 1. On follow-up imaging, no in-field failures have occurred. A total of 18.7% of the patients have had a failure elsewhere in the liver. Overall survival was 75% with 4 deaths, 2 of which were from liver failure and 2 from progressive systemic disease. Our preliminary study indicates that combination of liver SRT with hepatic resection is safe and effective. It can be used preoperatively to increase resectability or postoperatively to salvage surgical failures. It can also be used to target unresectable metastases in combination with limited hepatectomies for resectable peripheral lesions thereby expanding indications for curative treatment. SRT planning with 3D-SPECT/CT allows identification and preservation of the functional NLV.