Satoru Takahashi MD, Presenter: Nothing to Disclose

Keiko Akahane MD, Abstract Co-Author: Nothing to Disclose

Michiko Nakamura MD, Abstract Co-Author: Nothing to Disclose

Chiaki Shibayama MD, PhD, Abstract Co-Author: Nothing to Disclose

Yoshio Omori MD, PhD, Abstract Co-Author: Nothing to Disclose

Masanori Nakazawa MD, PhD, Abstract Co-Author: Nothing to Disclose

Eri Murakami Kashima MD, Abstract Co-Author: Nothing to Disclose

Yasumi Anno MD, Abstract Co-Author: Nothing to Disclose

Purpose/Objective(s):Irradiation of normal tissues, especially the left kidney, liver and spine is unavoidable in the conventional radiotherapy for gastric non-Hodgkin?s lymphoma (g-NHL). Late complications such as nephropathy and/or hypertension have been noted in association with kidney irradiation. We report an optimum half-field technique and the recent use of breath-hold method for g-NHL radiotherapy to prevent such damages to normal tissues. Materials/Methods:Between November 2002 and October 2007, 24 consecutive g-NHL cases were treated at our institution. Microscopic and immunohistological studies of the biopsy specimen showed the following diagnoses: diffuse large B-cell lymphoma (DLBCL) 8, mucosa-associated lymphoid tissue lymphoma (MALT) 16. MALT group included the cases not responding to Helicobacter pylori eradication. Half-field techniques by 10MV photon consisted the upper portion, which was treated with A-P/P-A fields, and the lower portion, which was irradiated bilaterally so as not to affect the both kidneys. The motion of the stomach, filled with diluted contrast agent, was monitored carefully to determine the appropriate margins in each treatment planning. The latter half of the series adopted the breath-hold technique to spare as much as normal tissues. A fractional dose of 1.5Gy was employed to a total of 40.5Gy for DLBCL and 30Gy for MALT. DVHs of the entire liver, bilateral kidneys, duodenum, and pancreas were obtained to compare the difference between this method and the conventional radiotherapy with 2 portals and/or 4 portals Results:Median follow-up period was 25 months (range 15-39 months) for DLBCL and 44 months (range 19-78 months) for MALT. Relapse-free survival/overall survival was 100%/100% and 93.4%/93.4%, respectively. No significant toxicities (>Grade 3) were noted in every case. Maximum doses of the left kidney were less than 3 Gy in most cases along with good DVHs for critical organs. Conclusions:Our optimum half-field technique utilizing breast-hold method demonstrated apparent improvement in the DVHs of the left kidney, liver and the spinal cord. Further study and longer follow-up observation warrants the validity of this method.

Takahashi, S, Akahane, K, Nakamura, M, Shibayama, C, Omori, Y, Nakazawa, M, Kashima, E, Anno, Y, Optimum Half-filed Radiotherapy Technique for Gastric Non-Hodgkin’s Lymphoma.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8501477.html