International Journal of Radiation Oncology � Biology � PhysicsS340

cardiac and pulmonary structures. Dose-volume histograms were calcu-

lated and analyzed in order to compare plans.

Results: The 3D proton plans showed decreased dose to partial volumes of

the entire heart, arteries, and left ventricle in comparison to both the IMRT

and 3D photon plans. The IMRT plans showed decreased dose delivered to

the LAD artery, pericardium, and left atrium in comparison to the 3D

photon plans (See Table).

Conclusions: For patients receiving radiation therapy for esophageal

cancer, proton plans are technically feasible with adequate coverage and

may results in lower dose to cardiac structures. This may result in

decreased cardiopulmonary toxicity and less morbidity to esophageal

cancer patients.

Author Disclosure: T.C. Ling: None. J.M. Slater: None. P. Nookala:

None. R. Mifflin: None. R. Grove: None. A.M. Ly: None. B. Patyal:

None. J.D. Slater: None. G.Y. Yang: None.

2309Long-Term Results of Chemoradiation Therapy for Stage II-IIIThoracic Esophageal Cancer: Comparison of 3 ProtocolsR. Umezawa, K. Jingu, T. Sugawara, M. Kubozono, K. Abe, T. Fujimoto,

T. Yamamoto, Y. Ishikawa, M. Kozumi, N. Kadoya, K. Takeda,

and H. Matsushita; Tohoku University School of Medicine, Sendai, Japan

Purpose/Objective(s): Chemoradiation therapy (CRT) is one of the

curative treatments for thoracic esophageal cancer. Although a platinum-

based combination regimen has been the standard regimen for esophageal

cancer, the optimal schedule and dose of chemotherapy have not been

established. We evaluated the long-term results of CRT for stage II-III

thoracic esophageal cancer by comparing results of three protocols

retrospectively.

Materials/Methods: Between 2000 and 2012, 298 patients with stage II-III(T1-4N0-1M0:UICC2002) thoracic esophageal cancer underwent CRT. All

patients had squamous cell carcinoma and were treated by the following

three protocols of CRT. Arm A consisted of two cycles of cisplatin

(CDDP) 70 mg/m2 (day 1 and 29) and 5-fluorouracil 700 mg/m2/24h (day

1-4 and 29-32) with radiation therapy (RT) of 60 Gy (30 fractions) without

a break. Arm B consisted of two cycles of CDDP 40 mg/m2 (day 1, 8, 36

and 43) and 5-fluorouracil 700 mg/m2/24h (day 1-5, 8-12, 36-40 and 43-

47) with radiation therapy (RT) of 60 Gy (30 fractions) including a two-

week break. Arm C consisted of two cycles of nedaplatin (CDGP) 70 mg/

m2 (day 1 and 29) and 5-fluorouracil 500 mg/m2/24h (day 1-4 and 29-32)

with radiation therapy (RT) of 60-70 Gy (30-35 fractions) without a break.

Overall survival (OS) and progression-free survival (PFS) were estimated

using the Kaplan-Meier method.

Results: The numbers of patients who underwent Arm A, Arm B and Arm

C were 48, 159 and 91, respectively. The median follow-up period was

22.3 months (range, 1.8-150.2 months). Two hundred eighty-eight patients

received the prescription dose. Two hundred fifty-six patients completed 2-

course chemotherapy. One hundred seventy-six patients achieved CR. The

3-year and 5-year OS rates were 51.1% and 43.4%, respectively. The 5-

year OS rates for stage II, stage III (non T4) and stage III (T4) were 64.1%,

40.3% and 21.7%, respectively (p < 0.001). The 5-year OS rates for Arm

A, Arm B and Arm C were 51.5% and 44.8 % and 37.2%, respectively (p

Z 0.105). The 5-year OS rates for patients receiving 2-course chemo-

therapy and 1-course chemotherapy were 45.8% and 26.5%, respectively

(p < 0.001). The 3-year and 5-year PFS rates were 36.3% and 31.1%,

respectively. The 5-year PFS rates for Arm A, Arm B and Arm C were

44.6%, 29.6 % and 29.5%, respectively (p Z 0.322). One hundred sixteen

patients had local recurrence. Salvage surgery and salvage endoscopic

therapy were performed in 49 and 16 patients, respectively.

Conclusions: CRT is effective for stage II-III thoracic esophageal cancer,

and long-term survival can be expected in some cases. There were no

significant differences between the three protocols in the present study.

The results of this study suggested the importance of performing 2-course

chemotherapy during RT.

Author Disclosure: R. Umezawa: None. K. Jingu: None. T. Sugawara:

None. M. Kubozono: None. K. Abe: None. T. Fujimoto: None.

T. Yamamoto: None. Y. Ishikawa: None.M. Kozumi: None. N. Kadoya:

None. K. Takeda: None. H. Matsushita: None.

2310Suggestion on Modification of Postoperative Radiation TherapyVolumes for Thoracic Esophageal Squamous Cell Carcinoma in StageIII or Positive Lymph NodesJ.L. Tan,1 Z.W. Cheng,2 and X.Z. Fen1; 1Cancer Hospital, Chinese

Academy of Medical Sciences, Beijing, China, 2Department of

Radiotherapy, Tianjin Medical University Cancer Institute and Hospital,

Tianjin, China

Purpose/Objective(s): To analyze the impact of the location of primary

tumor and the number of lymph nodes on the recurrence patterns after

surgical resection in patients with stage III or positive lymph node thoracic

esophageal squamous cell carcinoma (TESCC), and provide strategy to

optimize the target of postoperative radiation therapy.

Materials/Methods: This retrospective analysis included 538 patients who

had undergone R0 resection of TESCC with stage III or positive lymph

nodes in our Hospital from January 2004 to June 2009. Patients were

grouped into surgery alone (n Z 348, 64.5%) and surgery plus post-

operative IMRT (n Z 190, 35.5%). The Kaplan-Meier method was used to

calculate the survival rates, and the log-rank test was used for univariate

analysis. The chi-square test was used to analyze the sites of failure of

esophageal cancer with different treatments.

Results: For patients who underwent surgery alone and had lymph node

metastases not less than 2, there was no significant differences for overall

survival (OS) whichever the lymph node metastases existed in one or two

anatomic regions (p Z 0.987). While with the increased number of lymph

node metastases (N1, N2, N3), the OS decreased significantly (N1 vs N2:

p<0.001, N2 vs N3: p Z 0.009). For patients with upper, middle or lower

thoracic esophageal cancer, the rate of intrathoracic recurrence was 23.8%,

45.0% and 30.2% (p Z 0.021), the rate of supraclavicular lymph nodes

(SLNs) was 38.1%, 13.0% and 8.3% individually (p Z 0.001), while

distant metastasis exhibited no obvious differences (pZ 0.668). The lower

site of primary tumor (from upper to lower) and the more number of lymph

node metastasis (0-2, N2, N3), the higher rate of recurrence in abdominal

lymph node, of which was 0, 7.7% and 15.5% for the upper, middle and

lower primary tumor sites(pZ 0.033) and 6.8%, 12.8% and 18.8% for 0-2,

N2, N3 (p Z 0.162). The rate of abdominal lymph node recurrence was

below 5% for patients with middle esophageal cancer and 0-2 lymph node

metastasis, even if the lymph node metastasis took place in two anatomic

regions. For patients with middle or lower esophageal cancer and lymph

node metastasis not less than 3, the rate of abdominal lymph node recur-

rence in surgery alone group was 13.0% (10/77), which was higher than

that in postoperative IMRT group (3%, 1/32).

Conclusions: Patients with stage III or positive lymph node TESCC had

increased rate of metastasis, of which intrathoracic recurrence took place

most frequently. The location of primary tumor affected the rate of

recurrence. Our present study suggested that the radiation volume should

be modified according to the location of primary tumor and the number of

lymph node metastasis, and that the region of abdominal lymph node

should be included for patients with middle esophageal cancer and the

number of lymph node not less than 3 or for patients with lower esophageal

cancer.

Author Disclosure: J.L. Tan: None. Z.W. Cheng: None. X.Z. Fen: None.

2311The Significance of 3DCRT/VMAT Hybrid Plan to Reduce PericardialToxicity After Chemoradiation for Thoracic Esophageal CancerM. Myojin,1 S. Tanabe,1 K. Harada,1,2 H. Shirato,2 and M. Hosokawa3;1Department of Radiation Oncology, Keiyukai Sapporo Hospital, Sapporo,

Japan, 2Department of Radiation Medicine, Hokkaido University Graduate

School of medicine, Sapporo, Japan, 3Department of Surgery,

Keiyukaisapporo Hospital, Sapporo, Japan