Xiaomao Guo

Proton Beam Therapy and Concurrent Chemotherapy for Esophageal Cancer

PURPOSE Proton beam therapy (PBT) is a promising modality for the management of thoracic malignancies. We report our preliminary experience of treating esophageal cancer patients with concurrent chemotherapy (CChT) and PBT (CChT/PBT) at MD Anderson Cancer Center. METHODS AND MATERIALS This is an analysis of 62 esophageal cancer patients enrolled on a prospective study evaluating normal tissue toxicity from CChT/PBT from 2006 to 2010. Patients were treated with passive scattering PBT with two- or three-field beam arrangement using 180 to 250 MV protons. We used the Kaplan-Meier method to assess time-to-event outcomes and compared the distributions between groups using the log-rank test. RESULTS The median follow-up time was 20.1 months for survivors. The median age was 68 years (range, 38-86). Most patients were males (82%) who had adenocarcinomas (76%) and Stage II-III disease (84%). The median radiation dose was 50.4 Gy (RBE [relative biologic equivalence]) (range, 36-57.6). The most common grade 2 to 3 acute toxicities from CChT/PBT were esophagitis (46.8%), fatigue (43.6%), nausea (33.9%), anorexia (30.1%), and radiation dermatitis (16.1%). There were two cases of grade 2 and 3 radiation pneumonitis and two cases of grade 5 toxicities. A total of 29 patients (46.8%) received preoperative CChT/PBT, with one postoperative death. The pathologic complete response (pCR) rate for the surgical cohort was 28%, and the pCR and near CR rates (0%-1% residual cells) were 50%. While there were significantly fewer local-regional recurrences in the preoperative group (3/29) than in the definitive CChT/PBT group (16/33) (log-rank test, p = 0.005), there were no differences in distant metastatic (DM)-free interval or overall survival (OS) between the two groups. CONCLUSIONS This is the first report of patients treated with PBT/CChT for esophageal cancer. Our data suggest that this modality is associated with a few severe toxicities, but the pathologic response and clinical outcomes are encouraging. Prospective comparison with more traditional approach is warranted.

RADIATION-INDUCED CRANIAL NERVE PALSY: A CROSS-SECTIONAL STUDY OF NASOPHARYNGEAL CANCER PATIENTS AFTER DEFINITIVE RADIOTHERAPY

PURPOSE To address the characteristics and the causative factors of radiation-induced cranial nerve palsy (CNP) in nasopharyngeal carcinoma (NPC) patients with an extensive period of followed-up. PATIENTS AND METHODS A total of 317 consecutive and nonselected patients treated with definitive external-beam radiotherapy between November 1962 and February 1995 participated in this study. The median doses to the nasopharynx and upper neck were 71 Gy (range, 55-86 Gy) and 61 Gy (range, 34-72 Gy), respectively. Conventional fractionation was used in 287 patients (90.5%). Forty-five patients (14.2%) received chemotherapy. RESULTS The median follow-up was 11.4 years (range, 5.1-38.0 years). Ninety-eight patients (30.9%) developed CNP, with a median latent period of 7.6 years (range, 0.3-34 years). Patients had a higher rate of CNP (81 cases, 25.5%) in lower-group cranial nerves compared with upper group (44 cases, 13.9%) (χ(2) = 34.444, p < 0.001). Fifty-nine cases experienced CNP in more than one cranial nerve. Twenty-two of 27 cases (68.8%) of intragroup CNP and 11 of 32 cases (40.7%) of intergroup CNP occurred synchronously (χ(2) = 4.661, p = 0.031). The cumulative incidences of CNP were 10.4%, 22.4%, 35.5%, and 44.5% at 5, 10, 15, and 20 years, respectively. Multivariate analyses revealed that CNP at diagnosis, chemotherapy, total radiation dose to the nasopharynx, and upper neck fibrosis were independent risk factors for developing radiation-induced CNP. CONCLUSION Radiation-induced fibrosis may play an important role in radiation-induced CNP. The incidence of CNP after definitive radiotherapy for NPC remains high after long-term follow-up and is dose and fractionation dependent.

Comparison between continuous accelerated hyperfractionated and late-course accelerated hyperfractionated radiotherapy for esophageal carcinoma

PURPOSE To compare the treatment results and toxicity of continuous accelerated hyperfractionated (CAHF) and late-course accelerated hyperfractionated (LCAF) radiotherapy (RT) for esophageal carcinoma. METHODS AND MATERIALS Between August 1996 and March 1999, 101 patients with squamous cell carcinoma of the esophagus were randomized into two groups: 49 to the CAHF group and 52 to the LCAF group. Patients in the CAHF group received RT at 1.5 Gy/fraction b.i.d. (6-h interval), 5 d/wk, to a total dose 66 Gy in 44 fractions during 4.4 weeks. The patients in the LCAF group received conventional fractionation RT, 1.8 Gy/fraction, to a dose of 41.4 Gy in 23 fractions during 4.6 weeks, followed by accelerated fractionation RT using reduced fields, b.i.d., at 1.5 Gy/fraction, with a minimal interval of 6 h between fractions. The total dose was 68.4 Gy in 41 fraction during 6.4 weeks. Patient age, gender, performance score, diet, lesion location, lesion length, stage, and fractionation (CAHF or LCAF) were entered into the univariate and multivariate analyses. RESULTS All patients finished the treatment course, except for 1 patient in the CAHF group because of severe acute esophagitis. The rate of Grade I, II, and III acute bronchitis was 18.4% (9 of 49), 30.6% (15 of 49), and 8.2% (4 of 49) in the CAHF group and 13.5% (7 of 52), 21.2% (11 of 52), and 3.8% (2 of 52) in the LCAF group, respectively. However, the difference between the two groups was not statistically significant (p = 0.084). The rate of Grade I, II, III, and IV acute esophagitis was 6.1% (3 of 49), 32.7% (16 of 49), 46.9% (23 of 49), and 14.3% (7 of 49) in the CAHF group and 26.9% (14 of 52), 32.7% (17 of 52), 7.7% (4 of 52), and 1.9% (1 of 52) in the LCAF group, respectively. The difference was statistically significant (p < 0.001). The local control rate at 1, 2, and 3 years was 88.7%, 83.9%, and 55.9% in the CAHF group and 80.7%, 71.4%, and 57.1% in the LCAF group, respectively (p = 0.1251). The 1-, 2-, and 3-year survival rate was 79.6%, 51.6%, and 37.6% in the CAHF group and 80.0%, 57.6%, and 41.2% in the LCAF group, respectively (p = 0.5757). Multivariate analysis showed that age and lesion length were independent significant prognostic factors for local control rate, and age was for the overall survival rate. The fractionation schedule had no significant prognostic effect. CONCLUSION CAHF and LCAF result in similar 1-, 2-, and 3-year local control and survival rates. CAHF resulted in more severe acute esophagitis and may be less well tolerated than LCAF. The treatment results after the CAHF and LCAF regimens were better than those of historical conventional RT.

Post mastectomy linac IMRT irradiation of chest wall and regional nodes: dosimetry data and acute toxicities

BackgroundConventional post-mastectomy radiation therapy is delivered with tangential fields for chest wall and separate fields for regional nodes. Although chest wall and regional nodes delineation has been discussed with RTOG contouring atlas, CT-based planning to treat chest wall and regional nodes as a whole target has not been widely accepted. We herein discuss the dosimetric characteristics of a linac IMRT technique for treating chest wall and regional nodes as a whole PTV after modified radical mastectomy, and observe acute toxicities following irradiation.MethodsPatients indicated for PMRT were eligible. Chest wall and supra/infraclavicular region +/−internal mammary nodes were contoured as a whole PTV on planning CT. A simplified linac IMRT plan was designed using either integrated full beams or two segments of half beams split at caudal edge of clavicle head. DVHs were used to evaluate plans. The acute toxicities were followed up regularly.ResultsTotally, 85 patients were enrolled. Of these, 45 had left-sided lesions, and 35 received IMN irradiation. Planning designs yielded 55 integrated and 30 segmented plans, with median number of beams of 8 (6–12). The integrated and segmented plans had similar conformity (1.41±0.14 vs. 1.47±0.15, p=0.053) and homogeneity indexes (0.13±0.01 vs. 0.14±0.02, p=0.069). The percent volume of PTV receiving >110% prescription dose was <5%. As compared to segmented plans, integrated plans typically increased V5 of ipsilateral lung (p=0.005), and heart (p=0.001) in patients with left-sided lesions. Similarly, integrated plans had higher spinal cord Dmax (p=0.009), ipsilateral humeral head (p<0.001), and contralateral lung Dmean (p=0.019). During follow-up, 36 (42%) were identified to have ≥ grade 2 radiation dermatitis (RD). Of these, 35 developed moist desquamation. The median time to onset of moist desquamation was 6 (4–7) weeks from start of RT. The sites of moist desquamation were most frequently occurred in anterior axillary fold (32/35), and secondly chest wall (12/35). The difference in occurrence of ≥ grade 2 RD between integrated and segmented plans was statistically insignificant (X2=0.35, p=0.55). Only 2 were found to have grade 2 radiation pneumonitis.ConclusionsThe linac IMRT technique applied in PMRT with chest wall and regional nodes as a whole PTV was dosimetrically feasible, and the treatment was proved to be well-tolerated by most patients.

Stanniocalicin 2 Suppresses Breast Cancer Cell Migration and Invasion via the PKC/Claudin-1-Mediated Signaling

Stanniocalcin (STC), a glycoprotein hormone, is expressed in a wide variety of tissues to regulate Ca2+ and PO4- homeostasis. STC2, a member of STC family, has been reported to be associated with tumor development. In this study, we investigated whether the expression of STC2 is associated with migration and invasion of breast cancer cells. We found that breast cancer cell line 231 HM transfected with STC2 shRNA displayed high motility, fibroblast morphology, and enhanced cell migration and invasion. Introduction of STC2 in 231 cells reduced cell migration and invasion. In response to irradiation, silencing of STC2 in 231 HM cells reduced apoptosis, whereas overexpression of STC2 in 231 cells promoted apoptosis, compared with in control cells. Mechanistic study showed that STC2 negatively regulated PKC to control the expression of Claudin-1, which subsequently induced the expressions of EMT-related factors including ZEB1, ZO-1, Slug, Twist, and MMP9. Suppression of PKC activity by using a PKC inhibitor (Go 6983) restored the normal motility of STC2-silenced cells. Furthermore, in vivo animal assay showed that STC2 inhibited tumorigenesis and metastasis of breast cancer cells. Collectively, these results indicate that STC2 may inhibit EMT at least partially through the PKC/Claudin-1-mediated signaling in human breast cancer cells. Thus, STC2 may be exploited as a biomarker for metastasis and targeted therapy in human breast cancer.

A randomized phase II study of CEOP with or without semustine as induction chemotherapy in patients with stage IE/IIE extranodal NK/T-cell lymphoma, nasal type in the upper aerodigestive tract.

PURPOSE In this randomized phase II study, we evaluated the efficacy of semustine added to CEOP regimen as induction chemotherapy in patients with stage I(E)/II(E) extranodal NK/T-cell lymphoma, nasal type in the upper aerodigestive tract. PATIENTS AND METHODS Seventy-five eligible patients were randomized to receive either CEOP or CEOP plus semustine followed by involved-field radiotherapy. RESULTS The overall response rate of induction chemotherapy was 57.9% in CEOP arm compared with 62.2% in CEOP plus semustine arm (P=0.71). With a median follow-up of 30.1 months, 2-year overall survival was 73.3% and 62.2%, respectively (P=0.37). Toxicities in both arms were comparable and manageable. Through univariate and multivariate analysis, PS of 2, Stage II(E) and elevated LDH level were identified to be adverse prognostic factors. A new prognostic index categorized three groups of patients (low risk, no adverse factors; intermediate risk, one factor; and high risk, 2 or 3 factors) with highly significant difference of prognosis. Two-year overall survival was 87.5%, 60.6% and 30%, respectively (P=0.0002). CONCLUSIONS The addition of semustine to CEOP regimen was not associated with improved efficacy. More effective treatment needs to be explored in patients with intermediate or high risk.

Long-term outcome of irradiation with or without chemotherapy for esophageal squamous cell carcinoma: a final report on a prospective trial

PurposeTo investigate the long-term outcome of esophageal squamous cell carcinoma (SCC) treated by irradiation with or without concurrent chemotherapy.Methods and materialsA prospective clinical trial was carried out from 1998 to 2000. One hundred and eleven patients were randomly enrolled to receive either late course accelerated hyperfractionated irradiation (LCAF) or LCAF with concurrent chemotherapy (LCAF + CT). For LCAF, 41.4 Gy in 23 fractions was first delivered at five fractions per week, followed by 27 Gy in 18 fractions at two 1.5 Gy fractions a day. Concurrent chemotherapy of cis-platinum and 5-fluorouracil was administered for four cycles. Overall survival (OS), locoregional recurrence and distant metastasis were observed. Late toxicity was scored by RTOG criteria, and quality of life (QOL) was also evaluated.ResultsThe median follow-up time was 24 months for all patients and 138 months for 17 living patients. Median survival time was 25 months and 32 months in LCAF and LCAF + CT (p = 0.653), respectively. For an entire group of patients, overall survivals were 34%, 27% and 22%; locoregional recurrence rates were 30%, 36% and 41%; and distant metastasis rates were 26%, 28% and 29% at 5-yr, 8-yr and 10-yr, respectively. Incidences of ≥ Grade 3 late toxicity were 29% at 10-yr. There were no statistically significant differences between LCAF and LCAF + CT with respect to the parameters mentioned above. Cumulative incidence of late toxicities of ≥ Grade 3 increased sharply after the attained age of 70 years. Eighty-eight percent of patients lived with good KPS (≥ 90) and 94% could eat regular or soft diet.ConclusionThe long-term outcome of esophageal SCC patients who received LCAF or LCAF + CT was good. The locoregional and distant failures occurred more often in the first three years after treatment, but could continuously occur up to 10 years. The late toxicity was acceptable. Late toxicities ≥ Grade 3 were more likely to occur in elderly patients. QOL was good in living patients.

Systematic review and meta-analysis comparing hypofractionated with conventional fraction radiotherapy in treatment of early breast cancer.

BACKGROUND The purpose of this meta-analysis is to evaluate the efficacy and safety of altered radiation fraction size on outcomes for early breast cancer patients. METHODS A search of MEDLINE, EMBASE, WEB OF SCIENCE, Cochrane Library and ClinicalTrials.gov was conducted. Quality of the randomized controlled trials (RCTs) or non-RCTs were evaluated according to Cochranes risk of bias tool or Methodological Index for non-Randomized Studies (MINORS). Pooled risk ratio (RR) and 95% confidence interval (CI) were calculated. Subgroup analysis was applied according to different fraction dose and sensitivity analysis was performed according to RCTs or non-RCTs. RESULTS 23 studies were included in this systematic review. Meta-analysis demonstrated hypofractionation radiotherapy (HFRT) was associated with decreased grade 2/3 acute skin reactions compared with conventional fraction RT (CFRT), either 2.5-3.0 Gy per fraction or 5.0-6.5 Gy per fraction. HFRT with 2.5-3.0 Gy per fraction significantly decreased moderate/marked photographic changes in breast appearance compared with CFRT [RR = 0.80, 95% CI (0.70, 0.91), P = 0.001], while HFRT with more than 3.0 Gy per fraction significantly increased moderate/marked photographic changes [RR = 1.21, 95% CI (1.06, 1.38), P = 0.004]. In addition HFRT cost one-third lower than CFRT. Regarding to local regional recurrence, distant metastasis, overall survival, disease free survival, excellent/good cosmetic comes, symptomatic radiation pneumonitis, ischemic heart disease and symptomatic rib fracture, there was no significant difference between two arms. CONCLUSIONS Based on available evidence, HFRT with 2.5-3.0 Gy per fraction should be the better choice for treatment of early breast cancer patients.

Analysis in early stage triple-negative breast cancer treated with mastectomy without adjuvant radiotherapy: patterns of failure and prognostic factors.

The objective of this study was to evaluate and identify patterns of failure and prognostic factors for locoregional recurrence (LRR) that could justify postmastectomy radiotherapy after modified radical mastectomy in patients with early stage triple‐negative breast cancer.

The Chk1 inhibitor MK-8776 increases the radiosensitivity of human triple-negative breast cancer by inhibiting autophagy

MK-8776 is a recently described inhibitor that is highly selective for checkpoint kinase 1 (Chk1), which can weaken the DNA repair capacity in cancer cells to achieve chemo-sensitization. A number of studies show that MK-8776 enhances the cytotoxicity of hydroxyurea and gemcitabine without increasing normal tissue toxicities. Thus far, there is no evidence that MK-8776 can be used as a radiotherapy sensitization agent. In this study, we investigated the effects of MK-8776 on the radiosensitivity of 3 human triple-negative breast cancer (TNBC) cell lines MDA-MB-231, BT-549 and CAL-51. MK-8776 dose-dependently inhibited the proliferation of MDA-MB-231, BT-549 and CAL-51 cells with IC50 values of 9.4, 17.6 and 2.1 μmol/L, respectively. Compared with irradiation-alone treatment, pretreatment with a low dose of MK-8776 (100–400 nmol/L) significantly increased irradiation-induced γH2A.X foci in the 3 TNBC cell lines, suggesting enhanced DNA damage by MK-8776, inhibited the cell proliferation and increased the radiosensitivity of the 3 TNBC cell lines. Similar results were obtained in MDA-MB-231 xenograft tumors in nude mice that received MK-8776 (15 or 40 mg/kg, ip) 26 d after irradiation. To explore the mechanisms underlying the radio-sensitization by MK-8776, we used TEM and found that irradiation significantly increased the numbers of autophagosomes in the 3 TNBC cell lines. Moreover, irradiation markedly elevated the levels of Atg5, and promoted the transformation of LC3-I to LC3-II in the cells. Pretreatment with the low dose of MK-8776 suppressed these effects. The above results suggest that MK-8776 increases human TNBC radiosensitivity by inhibiting irradiation-induced autophagy and that MK-8776 may be a potential agent in the radiosensitization of human TNBC.