J.H. Maduro

Expression of epidermal growth factor receptor (EGFR) and activated EGFR predict poor response to (chemo)radiation and survival in cervical cancer

Purpose: Activation of the epidermal growth factor receptor (EGFR) signaling pathway has been reported to induce resistance to (chemo)radiation in cancers, such as head and neck cancer, whereas EGFR-targeted agents in combination with (chemo)radiation seem to improve treatment efficacy. The aim of this study was to determine the relation between proteins involved in the EGFR pathway and response to (chemo)radiation and survival in a large, well-documented series of cervical cancer patients. Experimental Design: Pretreatment tissue samples of 375 consecutive International Federation of Gynecologists and Obstetricians stage Ib to IVa cervical cancer patients treated with (chemo)radiation between January 1980 and December 2006 were collected. Clinicopathologic and follow-up data were prospectively obtained during standard treatment and follow-up. Protein expression of EGFR, phosphorylated EGFR (pEGFR), PTEN, phosphorylated AKT, and phosphorylated extracellular signal-regulated kinase (pERK) was assessed by immunohistochemistry on tissue microarrays. Results: EGFR staining was present in 35.3%, pEGFR in 19.7%, PTEN in 34.1%, phosphorylated AKT in 4.1%, and pERK in 29.2% of tumors. pEGFR staining was related to PTEN (P = 0.001) and pERK staining (P = 0.004). EGFR staining was inversely related to PTEN (P = 0.011). In multivariate analysis, membranous staining of EGFR [hazard ratio (HR), 1.84; 95% confidence interval (95% CI), 1.20-2.82; P = 0.005] and cytoplasmic staining of pEGFR (HR, 1.71; 95% CI, 1.11-2.66; P = 0.016) were independent predictors of poor response to (chemo)radiation. Membranous EGFR staining also was an independent prognostic factor for poor disease-specific survival (HR, 1.54; 95% CI, 1.09-2.17; P = 0.014). Conclusions: EGFR and pEGFR immunostainings are frequently observed and independently associated with poor response to therapy and disease-specific survival in cervical cancer patients primarily treated by (chemo)radiation. Our data present the EGFR pathway as a promising therapeutic target in already ongoing clinical trials. (Clin Cancer Res 2009;15(23):7389–97)

Proteasome inhibitor MG132 sensitizes HPV-positive human cervical cancer cells to rhTRAIL-induced apoptosis.

In cervical carcinogenesis, the p53 tumor suppressor pathway is disrupted by HPV (human papilloma virus) E6 oncogene expression. E6 targets p53 for rapid proteasome‐mediated degradation. We therefore investigated whether proteasome inhibition by MG132 could restore wild‐type p53 levels and sensitize HPV‐positive cervical cancer cell lines to apoptotic stimuli such as rhTRAIL (recombinant human TNF‐related apoptosis inducing ligand). In a panel of cervical cancer cell lines, CaSki was highly, HeLa intermediate and SiHa not sensitive to rhTRAIL‐induced apoptosis. MG132 strongly sensitized HeLa and SiHa to rhTRAIL‐induced apoptosis in a caspase‐dependent and time‐dependent manner. MG132 massively induced TRAIL receptor DR4 and DR5 membrane expression in HeLa, whereas in SiHa only DR5 membrane expression was upregulated from almost undetectable to high levels. Antagonistic DR4 antibody partially inhibited apoptosis induction by rhTRAIL and MG132 in HeLa but had no effect on apoptosis in SiHa. Inhibition of E6‐mediated p53 proteasomal degradation by MG132 resulted in elevated levels of active p53 as demonstrated by p53 small interfering RNA (siRNA) sensitive p21 upregulation. Although p53 siRNA partially inhibited MG132‐induced DR5 upregulation in HeLa and SiHa, no effect on rhTRAIL‐induced apoptosis was observed. MG132 plus rhTRAIL enhanced caspase 8 and caspase 3 activation and concomitant cleavage of X‐linked inhibitor of apoptosis (XIAP), particularly in HeLa. In addition, caspase 9 activation was only observed in HeLa. Downregulation of XIAP using siRNA in combination with rhTRAIL induced high levels of apoptosis in HeLa, whereas MG132 had to be added to the combination of XIAP siRNA plus rhTRAIL to induce apoptosis in SiHa. In conclusion, proteasome inhibition sensitized HPV‐positive cervical cancer cell lines to rhTRAIL independent of p53. Our results indicate that not only DR4 and DR5 upregulation but also XIAP inactivation contribute to rhTRAIL sensitization by MG132 in cervical cancer cell lines. Combining proteasome inhibitors with rhTRAIL may be therapeutically useful in cervical cancer treatment.

Clinical potential of inhibitors of survival pathways and activators of apoptotic pathways in treatment of cervical cancer: changing the apoptotic balance

Cervical cancer is the most common gynaecological malignant disorder worldwide. The best possible treatment of locally advanced cervical cancer is a combination of radiation and cisplatin-based chemotherapy. However, 5-year overall survival is still only 52%. To improve treatment results, research should focus on the discovery of innovative drug strategies. Drugs directed at inducing tumour-cell apoptosis are regarded as important treatment modalities. Here, we present an overview of the molecular options that can change the apoptotic balance in cervical cancer, through increasing death-receptor-mediated apoptosis, the use of proteasome inhibitors, short interfering RNAs, or non-steroidal anti-inflammatory drugs (NSAIDs). Furthermore, the potential of attacking prosurvival signalling through the epidermal-growth-factor receptor and insulin-like-growth-factor receptor to support the apoptotic process is discussed. Additional research is needed to elucidate the clinical potential of these compounds in the treatment of cervical cancer.

Simultaneous Integrated Boost Irradiation After Breast-Conserving Surgery: Physician-Rated Toxicity and Cosmetic Outcome at 30 Months' Follow-Up

PURPOSE To evaluate toxicity and cosmetic outcome (CO) in breast cancer survivors treated with three-dimensional conformal radiotherapy with a hypofractionated, simultaneous integrated boost (3D-CRT-SIB) and to identify risk factors for toxicity, with special focus on the impact of age. METHODS AND MATERIALS Included were 940 consecutive disease-free patients treated for breast cancer (Stage 0-III) with 3D-CRT-SIB, after breast-conserving surgery, from 2005 to 2010. Physician-rated toxicity (Common Terminology Criteria for Adverse Events version 3.0) and CO were prospectively assessed during yearly follow-up, up to 5 years after radiotherapy. Multivariate logistic regression analyses using a bootstrapping method were performed. RESULTS At 3 years, toxicity scores of 436 patients were available. Grade ≥ 2 fibrosis in the boost area was observed in 8.5%, non-boost fibrosis in 49.4%, pain to the chest wall in 6.7%, and fair/poor CO in 39.7% of cases. Radiotherapy before chemotherapy was significantly associated with grade ≥ 2 boost fibrosis at 3 years (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.3-6.0). Non-boost fibrosis was associated with re-resection (OR 2.2, 95% CI 1.2-4.0) and larger tumors (OR 1.1, 95% CI 1.0-1.1). At 1 year, chest wall pain was significantly associated with high boost dosage (OR 2.1, 95% CI 1.2-3.7) and younger age (OR 0.4, 95% CI 0.2-0.7). A fair/poor CO was observed more often after re-resection (OR 4.5, 95% CI 2.4-8.5), after regional radiotherapy (OR 2.9, 95% CI 1.2-7.1), and in larger tumors (OR 1.1, 95% CI 1.0-1.1). CONCLUSIONS Toxicity and CO are not impaired after 3D-CRT-SIB. Fibrosis was not significantly associated with radiotherapy parameters. Independent risk factors for fibrosis were chemotherapy after radiotherapy, re-resection, and larger tumor size. Re-resection was most predictive for worse CO. Age had an impact on chest wall pain occurrence.

Three-dimensional conformal hypofractionated simultaneous integrated boost in breast conserving therapy: Results on local control and survival

PURPOSE To report on local control and survival after breast conserving therapy (BCT) including three-dimensional conformal simultaneous integrated boost irradiation (3D-CRT-SIB) and on the influence of age on outcome. PATIENT AND METHODS For this study, 752 consecutive female breast cancer patients (stages I-III), treated with 3D-CRT-SIB at the University Medical Center Groningen from 2005 to 2008, were retrospectively identified. Median age was 58.4 (range 26-84) years. The SIB fractionation used was: 28×1.8Gy (whole breast) and 28×2.3Gy or 2.4Gy (tumour bed). Next to outcome, we estimated the effect of age on the recurrence-free period (RFP) by multivariate Cox regression survival analysis. RESULTS Median follow-up was 41 (range 3-65) months. Local control was 99.6% at 3 years (6 ipsilateral recurrences). The 3-year locoregional control, RFP and overall survival (OS) rates were 99.2%, 95.5%, and 97.1%, respectively. In multivariate analysis, tumours >2cm (hazard ratio (HR) 3.11; 95% confidence interval (CI) 1.57-6.17) and triple negativity (HR 3.03; 95% CI 1.37-6.67) and not age were associated with impaired RFP. CONCLUSIONS At 3 years, the 3D-CRT-SIB technique in BCT results in excellent local control and OS. Age was not a risk factor for any recurrence.

EARLY-STAGE YOUNG BREAST CANCER PATIENTS : IMPACT OF LOCAL TREATMENT ON SURVIVAL

PURPOSE In young women, breast-conserving therapy (BCT), i.e., lumpectomy followed by radiotherapy, has been associated with an increased risk of local recurrence. Still, there is insufficient evidence that BCT impairs survival. The aim of our study was to compare the effect of BCT with mastectomy on overall survival (OS) in young women with early-stage breast cancer. METHODS AND MATERIALS From two Dutch regional population-based cancer registries (covering 6.2 million inhabitants) 1,453 women <40 years with pathologically T1N0-1M0 breast cancer were selected. Cox regression survival analysis was used to study the effect of local treatment (BCT vs. mastectomy) stratified for nodal stage on survival and corrected for tumor size, age, period of diagnosis, and use of adjuvant systemic therapy. RESULTS With a median follow-up of 9.6 years, 10-year OS was 83% after BCT and 78% after mastectomy, respectively (unadjusted hazard ratio [HR], 1.37; 95% confidence interval [CI], 1.09-1.72). In N0-patients, 10-year OS was 84% after BCT and 81% after mastectomy and local treatment was not associated with differences in OS (HR 1.19; 95% CI, 0.89-1.58; p = 0.25). Within the N1-patient group, OS was better after BCT compared with mastectomy, 79% vs. 71% at 10 years (HR 1.91; 95% CI, 1.28-2.84; p = 0.001) and in patients treated with adjuvant hormonal therapy (HR 0.34; 95% CI, 0.18-0.66; p = 0.001). CONCLUSIONS In this large population-based cohort of early-stage young breast cancer patients, 10-year OS was not impaired after BCT compared with mastectomy. Patients with 1 to 3 positive lymph nodes had better prognosis after BCT than after mastectomy.

Validation and Modification of a Prediction Model for Acute Cardiac Events in Patients With Breast Cancer Treated With Radiotherapy Based on Three-Dimensional Dose Distributions to Cardiac Substructures

Purpose A relationship between mean heart dose (MHD) and acute coronary event (ACE) rate was reported in a study of patients with breast cancer (BC). The main objective of our cohort study was to validate this relationship and investigate if other dose-distribution parameters are better predictors for ACEs than MHD. Patients and Methods The cohort consisted of 910 consecutive female patients with BC treated with radiotherapy (RT) after breast-conserving surgery. The primary end point was cumulative incidence of ACEs within 9 years of follow-up. Both MHD and various dose-distribution parameters of the cardiac substructures were collected from three-dimensional computed tomography planning data. Results The median MHD was 2.37 Gy (range, 0.51 to 15.25 Gy). The median follow-up time was 7.6 years (range, 0.1 to 10.1 years), during which 30 patients experienced an ACE. The cumulative incidence of ACE increased by 16.5% per Gy (95% CI, 0.6 to 35.0; P = .042). Analysis showed that the volume of the left ventricle receiving 5 Gy (LV-V5) was the most important prognostic dose-volume parameter. The most optimal multivariable normal tissue complication probability model for ACEs consisted of LV-V5, age, and weighted ACE risk score per patient (c-statistic, 0.83; 95% CI, 0.75 to 0.91). Conclusion A significant dose-effect relationship was found for ACEs within 9 years after RT. Using MHD, the relative increase per Gy was similar to that reported in the previous study. In addition, LV-V5 seemed to be a better predictor for ACEs than MHD. This study confirms the importance of reducing exposure of the heart to radiation to avoid excess risk of ACEs after radiotherapy for BC.

THE PROGNOSTIC VALUE OF TRAIL AND ITS DEATH RECEPTORS IN CERVICAL CANCER

PURPOSE Preclinical data indicate a synergistic effect on apoptosis between irradiation and recombinant human (rh) tumor necrosis factor-related apoptosis inducing ligand (TRAIL), making the TRAIL death receptors (DR) interesting drug targets. The aim of our study was to analyze the expression of DR4, DR5, and TRAIL in cervical cancer and to determine their predictive and prognostic value. METHODS AND MATERIALS Tissue microarrays were constructed from tumors of 645 cervical cancer patients treated with surgery and/or (chemo-)radiation between 1980 and 2004. DR4, DR5, and TRAIL expression in the tumor was studied by immunohistochemistry and correlated to clinicopathological variables, response to radiotherapy, and disease-specific survival. RESULTS Cytoplasmatic DR4, DR5, and TRAIL immunostaining were observed in cervical tumors from 99%, 88%, and 81% of the patients, respectively. In patients treated primarily with radiotherapy, TRAIL-positive tumors less frequently obtained a pathological complete response than TRAIL-negative tumors (66.3% vs. 79.0 %; in multivariate analysis: odds ratio: 2.09, p </=0.05). DR4, DR5, and TRAIL expression were not prognostic for disease-specific survival. CONCLUSIONS Immunostaining for DR4, DR5, and TRAIL is frequently observed in the cytoplasm of tumor cells in cervical cancer patients. Absence of TRAIL expression was associated with a higher pathological complete response rate to radiotherapy. DR4, DR5, or TRAIL were not prognostic for disease-specific survival.

Dosimetric consequences of the shift towards computed tomography guided target definition and planning for breast conserving radiotherapy

BackgroundThe shift from conventional two-dimensional (2D) to three-dimensional (3D)-conformal target definition and dose-planning seems to have introduced volumetric as well as geometric changes. The purpose of this study was to compare coverage of computed tomography (CT)-based breast and boost planning target volumes (PTV), absolute volumes irradiated, and dose delivered to the organs at risk with conventional 2D and 3D-conformal breast conserving radiotherapy.MethodsTwenty-five patients with left-sided breast cancer were subject of CT-guided target definition and 3D-conformal dose-planning, and conventionally defined target volumes and treatment plans were reconstructed on the planning CT. Accumulated dose-distributions were calculated for the conventional and 3D-conformal dose-plans, taking into account a prescribed dose of 50 Gy for the breast plans and 16 Gy for the boost plans.ResultsWith conventional treatment plans, CT-based breast and boost PTVs received the intended dose in 78% and 32% of the patients, respectively, and smaller volumes received the prescribed breast and boost doses compared with 3D-conformal dose-planning. The mean lung dose, the volume of the lungs receiving > 20 Gy, the mean heart dose, and volume of the heart receiving > 30 Gy were significantly less with conventional treatment plans. Specific areas within the breast and boost PTVs systematically received a lower than intended dose with conventional treatment plans.ConclusionThe shift towards CT-guided target definition and planning as the golden standard for breast conserving radiotherapy has resulted in improved target coverage at the cost of larger irradiated volumes and an increased dose delivered to organs at risk. Tissue is now included into the breast and boost target volumes that was never explicitly defined or included with conventional treatment. Therefore, a coherent definition of the breast and boost target volumes is needed, based on clinical data confirming tumour control probability and normal tissue complication probability with the use of 3D-conformal radiotherapy.

Minimising contralateral breast dose in post-mastectomy intensity-modulated radiotherapy by incorporating conformal electron irradiation

PURPOSE To assess the potential benefit of incorporating conformal electron irradiation in intensity-modulated radiotherapy (IMRT) for loco-regional post-mastectomy RT. PATIENTS AND METHODS Ten consecutive patients that underwent left-sided mastectomy were selected for this comparative planning study. Three-dimensional conformal radiotherapy (3D-CRT) photon-electron dose plans were compared to photon-only IMRT (IMRT(p)) and photon IMRT with conformal electron irradiation (IMRT(p/e)). The planning target volume (PTV) was prescribed 50 Gy and included the chest wall and the internal mammary and supra-clavicular lymph node regions. It was attempted to minimise dose delivered to heart, lungs and contralateral breast (CB), while maintaining adequate PTV coverage. RESULTS All plans complied with objectives for PTV coverage. IMRT(p/e) eliminated volumes receiving 70 Gy (V70) that were present in 3D-CRT at the junction of photon and electron beams. Both IMRT strategies reduced heart V30 significantly below 3D-CRT levels. Mean heart dose with IMRT(p/e) was the lowest and was equal to that with 3D-CRT. Minimising heart dose with IMRT(p) resulted in irradiated CB volumes much larger than that with 3D-CRT. With IMRT(p/e), CB dose was only slightly increased when compared to 3D-CRT. Mean lung dose values were similar for IMRT and 3D-CRT. With IMRT, lung V20 was smaller, whereas V5 values for heart, lung and CB were higher than those with 3D-CRT. CONCLUSIONS Incorporation of conformal electron irradiation in post-mastectomy IMRT(p/e) enables a heart dose reduction which can only be obtained with IMRT(p) when allowing large irradiated volumes in the contralateral breast.