Image-Guided Stereotactic Radiosurgery for Locally Advanced Pancreatic Adenocarcinoma Results of First 85 Patients
Mukund S. Didolkar*1, Cardella Coleman2, Mark J. Brenner2, Kyo U. Chu1, Elizabeth Stanwyck3, Airong Yu3, Nicole Olexa1, Nagaraj Neerchal3
1Surgical Oncology, Sinai Hospital of Baltimore, Baltimore, MD; 2Radiation Oncology, Sinai Hospital of Baltimore, Baltimore, MD; 3Department of Mathematics, University of Maryland at Baltimore County Campus, Baltimore, MD
BACKGROUND:Locally advanced unresectable pancreatic adenocarcinoma is characterized by poor survival despite chemotherapy and conventional radiation therapy. Recent advances in real time image-guided stereotactic radiosurgery (SRS) has made it possible to treat these cancers in 3-4 fractions followed by systemic chemotherapy. AIMS:1. To obtain local control of the disease. 2. To improve the survival of these unresectable patients. 3. To evaluate the toxicity of SRS. 4. Report results of the largest series from a single center.METHODS: Pancreatic SRS involves delivery of high doses of accurately targeted radiation given non-invasively in 2-4 fractions. We treated 85 consecutive patients with locally advanced and recurrent pancreatic adenocarcinoma from Feb 2004 to Aug 2009.Age range: 36-87, mean 65 years; Sex: males 50, females 35; Race: Caucasian 74, others 11; Histology: adenocarcinoma 82, islet cell 2, other 1; T stage III/IV 81, TX 4; N stage N+ 39, NX 46; M stage M0 60, M1 25. No prior surgical resection in 70 patients, and 15 had local recurrence after surgical resection. 30 patients had progression of disease after prior conventional radiation therapy (RT). Location of the tumor: head 55, body and tail 30. All patients received gemcitabine-based chemotherapy regimen after SRS and some had additional chemotherapy before SRS. Median tumor volume 62 cc. PET/CT scans done in latter 43 patients showed an average SUV of 6.9. Pain score (1-10): <3 35, >4 50.SRS doses ranged from 15 to 30 Gy with the mean dose of 25.5 Gy delivered in 3 days (range 2-5 days) divided in equal fractions. Mean conformity index of 1.6 and mean isodose line of 80%.RESULTS: Tumor control: complete, partial, and stable disease was observed in 75 patients for the duration of 3-36 mos. Pain relief was noted in 45 of 50 patients. Most of the patients died of distant progression. SURVIVAL: Survival of was calculated by Kaplan-Meier method. Overall mean survival 23.9 mos and from SRS was 13.7 mos. For the group of 41 patients without prior surgical resection or conventional RT and no distant metasteses, the average survival was 17.7 mos from the diagnosis and 13.5 mos from SRS.TOXICITY:Grade III and IV duodenitis 8 (9.4%), gastritis 12 (14.1%), diarrhea 3 (3.5%), renal failure 1 (1.2%). 6 week post mortality was 0%.CONCLUSIONS: SRS for unresectable pancreatic carcinoma can be delivered in 3 fractions with minimal morbidity and a local tumor control rate of 88.2%.The survival is better compared to the reported results for advanced pancreatic cancer, specifically for the group of previously untreated patients with unresectable tumors.
Back to Program
