| Part1:Study the pattern and prognostic factor of lymph node metastasis in patients with thoracic esophageal squamous cell carcinomaPurpose:To study the pattern and prognostic factors of lymph node metastases after radical esophagectomy, and identify the clinical target volume (CTV) delineation of thoracic esophageal squamous cell carcinoma (ESCC).Methods and materials:Total 414 thoracic ESCC patients who had undergone esophagectomy and lymphadenectomy with radical resection of the cervix,chest and abdomen lymph node regions dissection were retrospectively reviewed. The clinical and pathologic factors related to lymph node metastasis and regional clusters of lymph node metastasis and regional lymph node metastasis skipping were analyzed using Chi-square test and logistic regression analysis.Results:The overall rates of lymph node metastasis:62.8% (260/414). The lymph node metastasis rates in patients with upper, middle and lower thoracic tumors were:69.7% (46/66),60.3%(161/267) and 65.4%(53/81), respectively. There was no significantly statistical difference among the rates of lymph node metastasis in upper, middle and lower thoracic tumors (P= 0.317).The rates of lymph node metastases in patients with upper thoracic tumors were 39.4% (26/66)cervical,39.4% (26/66) upper mediastinal,10.6% (7/66) middle mediastinal,0% (0/66) lower mediastinal,and 6.1% (4/66) abdominal, respectively. The rates of lymph node metastases in patients with middlethoracic tumors were 28.8% (77/267),24.4% (66/267),24.3% (65/267),10.5% (28/267), and 18.4% (49/267),respectively. The rates of lymph node metastases in patients with lower thoracic tumors were 28.4% (23/81),24.7%(20/81),16%(13/81),28.4% (23/81), and 42%(34/81), respectively.Univariate analysis showed that T stage (P=0.019),histological differentiation (P= 0.051) and tumor length (P=0.044) emerged as statistically significant risk factors of lymph node metastases of the upper thoracic ESCC (P< 0.001).Multivariate analysis showed that T stage emerged as statistically significant risk factors of lymph node metastases in the the upper (P<0.001) and middle thoracic (P=0.009) ESCCThe lymph node metastasis rates of locoregional regions in upper,middle,lower thoracic esophageal squamous cell carcinoma were 63.6%(42/66),21.7%(58/267), 38.6%(103/267), respectively.The lymph node metastasis rates of distant regions with upper,middle,lower thoracic esophageal squamous cell carcinoma were 6.1%(4/66), 23.5%(19/81),42%(34/81), respectively.There was significantly statistical difference among the regional clusters of lymph node metastasis in upper, middle and lower thoracic tumors (P<0.01).Univariate and Multivariate analysis showed that T stage emerged as statistically significant risk factors of distant regional distant lymph node metastasis of the middle thoracic ESCC (P< 0.05). No variables was significantly correlated with distant regional lymph node metastasis in the lower thoracic esophageal squamous cell carcinoma.The rates of lymph node skipping metastases in patients with upper thoracic, middle thoracic, lower thoracic tumors were 1.5%(1/66),19.1%(51/267),11.1%(9 /81) respectively. There was significantly statistical difference among the rates of lymph node skipping metastasis in upper, middle and lower thoracic tumors (P= 0.001).Univariate and Multivariate analysis showed that no clinicopathological characteristics emerged as statistically significant risk factors of skipping metastasis of the middle thoracic ESCC。Univariate analysis showed that T stage (P= 0.003) and pathological differentiation (P= 0.01) emerged as statistically significant risk factors of skipping metastasis of the lower thoracic ESCC.Conclusions:The rates of lymph node metastases in thoracic esophageal squamous cell carcinoma is high. There was no significantly difference among the rates of lymph node metastasis in upper, middle and lower thoracic tumors.T stage influence the pattern of lymphnode metastases in thoracic ESCC.The regional clusters of lymph node metastasis was observered in the upper thoracic ESCC. The lymph node metastasis was diffuse in the middle and lower thoracic ESCC.T stage was a prognostic factor for lymph node clustering in the middle thoracic ESCC. The rates of lymph node skipping metastases was also high in the middle and lower thoracic ESCC. No characteristics was found to predict the skipping metastasis of lymph node in the middle and lower thoracic ESCCThese factors should be considered comprehensively to design the CTV for radiotherapy (RT) of thoracic ESCC. Selective regional irradiation including the correlated lymphatic drainage regions should be performed in the upper thoracic ESCC as well. Part2:Study of feasibility for primary tumor and selective regional irradiation including the correlated lymphatic drainage regions in patients with unoperative upper thoracic ESCCPurpose:To evaluate the dosimetric feasibility for primary tumor and selective regional irradiation including the correlated lymphatic drainage regions using IMRT in patients with unoperative upper thoracic ESCC.Methods and materials:.8 patients with upper thoracic ESCC who received radiotherapy or chemoradiation were retrospectively reviewed. The gross tumor volume (GTV) was defined as any visible primary tumor and metastatic lymph nodes; The CTV for the primary tumor includes 2 cm above and below primary tumor with no radial expansion of GTV; The CTV for lymphatic drainage regions includes the cervix, the upper mediastinal and the middle mediastinal lymphatic drainage regions; PTVg was defined as 1 cm expansion of GTV; PTVc as 0.8-lcm expansion of CTV. Patients received 63 Gy in 28 fractions over 40 days for PTVg,50.4 Gy in 28 fractions over 40 days for PTVc, using SIB-IMRT.The SIB-IMRT plans were generated by Philips Picnical3, treatment-planning system. Irradiation was delivered with 6-MV photon energy.Plan optimization was based on the dose-volume histogram(DVH), the prescribed isodose curve covered 95% of the PTVg and PTVc; the 95% isodose curve covered 99%of the PTVg and PTVc.The dose constraints to the organs at risk were as follows:(1) the mean lung dose (MLD) was<=15 Gy, and the V20 (the percentage of the total lung volume receiving >=20Gy) was<=25%, the V5 was<=50%-60%(2) the mean heart dose (MHD) was <=40 Gy, and the V30 (the percentage of the total heart volume receiving>=30Gy) was<=30%(3) the maximum spinal cord dose was<=45 Gy.Median,maximum, minimum and standard deviation values with target and organs at risk were analyzed using SPSS 13.0 package.Results:The median values of PTVgVOL,PTVgD95,PTVgD99,PTVgDmax,PTVgDmin,PTVgDmax/PTVgDmin,PTVcVOL,PTVcD95,PTVcD99,PTVcDmax,PTVcDmin,PTVcDmax/PTVcDmin for target with 8 cases in upper thoracic esophageal cancer:were 278.97,62.98,60.8,71.26,51.74,1.365,687.445,53.95,50.85,71.26,26.99,2.69, respectively. The median values of spinalcordDmax,cordV45,lungMLD,lungV5,lungV20,heartMHD were 44.43,0,12.49,0.52,0.23,7.81 respectively.Conclusions:Our results indicated that accelerated radiotherapy with SIB-IMRT, with primary tumor and selective regional irradiation including the correlated lymphatic drainage regions(cervix, upper mediastinum, and middle mediastinal lymphatic drainage regions) is a feasible treatment modality, for patients with unoperative upper thoracic ESCC... |
PDF Full Text Request