M. Loi

Synergy of Radiotherapy and a Cancer Vaccine for the Treatment of HPV-Associated Head and Neck Cancer

There is growing interest in the association of radiotherapy and immunotherapy for the treatment of solid tumors. Here, we report an extremely effective combination of local irradiation (IR) and Shiga Toxin B (STxB)–based human papillomavirus (HPV) vaccination for the treatment of HPV-associated head and neck squamous cell carcinoma (HNSCC). The efficacy of the irradiation and vaccine association was tested using a model of HNSCC obtained by grafting TC-1/luciferase cells at a submucosal site of the inner lip of immunocompetent mice. Irradiation and the STxB-E7 vaccine acted synergistically with both single and fractionated irradiation schemes, resulting in complete tumor clearance in the majority of the treated mice. A dose threshold of 7.5 Gy was required to elicit the dramatic antitumor response. The combined treatment induced high levels of tumor-infiltrating, antigen-specific CD8+ T cells, which were required to trigger the antitumor activity. Treatment with STxB-E7 and irradiation induced CD8+ T-cell memory, which was sufficient to exert complete antitumor responses in both local recurrences and distant metastases. We also report for the first time that a combination therapy based on local irradiation and vaccination induces an increased pericyte coverage (as shown by αSMA and NG2 staining) and ICAM-1 expression on vessels. This was associated with enhanced intratumor vascular permeability that correlated with the antitumor response, suggesting that the combination therapy could also act through an increased accessibility for immune cells. The combination strategy proposed here offers a promising approach that could potentially be transferred into early-phase clinical trials. Mol Cancer Ther; 14(6); 1336–45. ©2015 AACR.

Gamma Knife Radiosurgery in the management of single and multiple brain metastases.

OBJECTIVES To evaluate the efficacy and safety of Gamma Knife Radiosurgery (GKRS) in the treatment of single and multiple brain metastases. PATIENTS AND METHODS From October 2012 to June 2014 106 patients were treated with Radiosurgery (RS) for brain metastases at University of Florence. 77 out of 106 patients had a radiological follow up and their data were analyzed. The target was defined as the enhancing lesion. The prescription dose was defined depending on tumor volume and tumor location. Each patient performed an MRI one month after GKRS for the first three months and every 3 months thereafter. Overall survival was calculated from the day of RS until death. Local recurrence (LR) was defined as radiologic growth of the irradiated lesion, while distant brain recurrence (DBR) was the evidence of brain lesion outside the previous irradiated field. Both the LR and DBR were calculated from the RS till the day of radiological evidence of relapse. The correlations within patient and disease characteristics and the outcomes of survival and disease control were analyzed. RESULTS Mean follow up was 7.2 ± 4.8 months (range: 2.4-22.8 months). At the time of analysis 21 patients (27.3%) were dead. The overall survival (OS) at 1 year was 74%. On univariate Cox Regression analysis female gender (p=0.043, HR: 0.391, 95% CI: 0.157-0.972) and age >65 years (p=0.003 HR: 4.623, 95% CI: 1.687-12.663) were predictive for survival. On multivariate analysis, age older than 65 years (p=0.005HR: 4.254, 95% CI: 1.544-11.721) was confirmed as associated with worsened overall survival. 19 patients (24.7%) had recurrence in the radiosurgery field. The median time to local failure was 4.8 ± 2.0 months (range: 1.8-9.4 months) from GKRS. On Cox Regression univariate analysis, the only factor associated with higher risk of local failure was a number of treated lesions more than 4 (p=0.015, HR: 3.813, 95% CI: 1.298-11.202), no significant parameters were found at the multivariate analysis. The median time to develop distant brain failure was 6 ± 4.32 months (range: 1.08-21.6 months). Median distant brain control was 74% at 1 year. None of the factors analyzed was statistically significant for the distant brain relapse. The radiosurgery treatment was well tolerated. One patient treated for seven metastases developed seizures 8h after GKRS, he was treated with steroids and anticonvulsants. One patient had radiologic evidence of radionecrosis without any neurological symptoms. CONCLUSIONS In well-performing patients with stable systemic disease radiosurgery can be performed as an exclusive treatment for brain metastases. Younger patients could have a greater benefit from the RS, on the other hand our finding confirm no correlation between the survival outcome and the number of lesions treated.

Prognostic Role of Human Epidermal Growth Factor Receptor 2 Status in Premenopausal Early Breast Cancer Treated With Adjuvant Tamoxifen

BACKGROUND Hormone therapy is the most prescribed systemic therapy for patients with breast cancer (BC). Some patients fail to respond to tamoxifen; one pathway seems to involve human epidermal growth factor receptor 2 (HER2) overexpression. To better understand this matter, we reviewed our single-center experience of premenopausal patients who were chemotherapy naive and treated with 5 years of tamoxifen for early-stage BC by focusing on estrogen receptor (ER), progesterone receptor, HER2 status, and Ki-67 proliferative index. PATIENTS AND METHODS We reviewed 425 patients treated with tamoxifen for early-stage BC. Previous solid tumors, age less than 18 years, BC recurrences or contralateral tumor, tamoxifen discontinuation, adjuvant chemotherapy, and a follow-up shorter than 6 months were considered exclusions criteria of the study. RESULTS At a mean follow-up of 8.1 years, the mean (SD) time to local relapse was 6.7 ± 3.6 years; range, 2.0-10.7 years), whereas the mean (SD) time to distant metastases was 4.7 ± 2.3 years; range, 2.2-8.8 years). HER2 status did not influence local relapse-free survival (log-rank test, 0.40), distant metastases-free survival (log-rank test, 0.72), and overall survival rate (log-rank test, 0.87). CONCLUSIONS Resistance to tamoxifen is a complex trait, and its pathway is still unclear; in patients with BC, a multidisciplinary approach is highly recommended. In our experience, we did not find a statistically significant difference in tamoxifen treatment efficacy according to HER2 status.

A PPAR-gamma agonist protects from radiation-induced intestinal toxicity

Objective Because of its anti-inflammatory, anti-fibrotic, anti-apoptotic and anti-neoplastic properties, the PPAR-γ agonist rosiglitazone is an interesting drug for investigating for use in the prevention and treatment of radiation-induced intestinal damage. We aimed to evaluate the radioprotective effect of rosiglitazone in a murine model of acute intestinal damage, assessing whether radioprotection is selective for normal tissues or also occurs in tumour cells. Methods Mice were total-body irradiated (12 Gy), with or without rosiglitazone (5 mg/kg/day). After 24 and 72 hours, mice were sacrificed and the jejunum was collected. HT-29 human colon cancer cells were irradiated with a single dose of 2 (1000 cells), 4 (1500 cells) or 6 (2000 cells) Gy, with or without adding rosiglitazone (20 µM) 1 hour before irradiation. HT-29-xenografted CD1 mice were irradiated (16 Gy) with or without rosiglitazone; tumour volumes were measured for 33 days. Results Rosiglitazone markedly reduced histological signs of altered bowel structures, that is, villi shortening, submucosal thickening, necrotic changes in crypts, oedema, apoptosis, and inflammatory infiltrate induced by irradiation. Rosiglitazone significantly decreased p-NF-kB p65 phosphorylation and TGFβ protein expression at 24 and 72 hours post-irradiation and significantly decreased gene expression of Collagen1, Mmp13, Tnfα and Bax at 24 hours and p53 at 72 hours post-irradiation. Rosiglitazone reduced HT-29 clonogenic survival, but only produced a slight reduction of xenograft tumour growth. Conclusion Rosiglitazone exerts a protective effect on normal tissues and reduces alterations in bowel structures and inflammation in a radiation-induced bowel toxicity model, without interfering with the radiation effect on HT-29 cancer cells. PPAR-γ agonists should be further investigated for their application in abdominal and pelvic irradiation.

A PPAR gamma agonist protects against oral mucositis induced by irradiation in a murine model

BACKGROUND Due to its anti-inflammatory, antifibrotic and antineoplastic properties, the PPAR gamma agonist rosiglitazone is of interest in prevention and therapy of radiation-induced toxicities. We aimed to evaluate the radioprotective effect of rosiglitazone in a mouse model of radiation-induced oral mucositis. MATERIAL AND METHODS Oral mucositis was obtained by irradiation of the oral region of C57BL/6J mice, pretreated or not with rosiglitazone. Mucositis was assessed by macroscopic scoring, histology and molecular analysis. Tumor xenograft was obtained by s.c. injection of Hep-2 cells in CD1 mice. Tumor volume was measured twice a week to evaluate effect of rosiglitazone alone and combined with radiotherapy. RESULTS Irradiated mice showed typical features of oral mucositis, such as oedema and reddening, reaching the peak of damage after 12-15days. Rosiglitazone markedly reduced visible signs of mucositis and significantly reduced the peak. Histological analysis showed the presence of an inflammatory cell infiltrate after irradiation; the association with rosiglitazone noticeably reduced infiltration. Rosiglitazone significantly inhibited radiation-induced tnfα, Il-6 and Il-1β gene expression. Rosiglitazone controlled the increase of TGF-β and NF-kB p65 subunit proteins induced by irradiation, and enhanced the expression of catalase. Irradiation and rosiglitazone significantly reduced tumor volume as compared to control. Rosiglitazone did not protect tumor from the therapeutic effect of radiation. CONCLUSION Rosiglitazone exerted a protective action on normal tissues in radiation-induced mucositis. Moreover, it showed antineoplastic properties on head-neck carcinoma xenograft model and selective protection of normal tissues. Thus, PPAR gamma agonists should be further investigated as radioprotective agents in head and neck cancer.

Radiotherapy in the age of cancer immunology: Current concepts and future developments

Major advances in the knowledge of cancer biology and its interactions with tumor immune environment led to the emergence, in the last five years of new immunotherapy-based treatment strategies in cancer patients. At the same time, improvement in radiation technique and progress in radiobiology allowed in the last decade to expand the applications of radiotherapy in a growing number of settings. At present, there are strong theoretical basis to propose immune-enhanced radiation therapy that may represent in the future a new paradigm of treatment, combining the intrinsic power of radiotherapy to elicit a specific, systemic, tumor-directed immune response with modern highly conformal and precise dose delivery, in order to maximize response at the major site of disease and obtain durable disease control. The aim of this review is to describe the principal mechanisms of immune modulation of response to radiation and investigational strategies to harness the potential of radiation-inducible immune response: radiation therapy is expected to be not just a local treatment but the cornerstone of a multimodal strategy that might achieve long-lasting tumor remission at the primary site and systemic efficacy metastatic lesions.

Incidence of skin toxicity in squamous cell carcinoma of the head and neck treated with radiotherapy and cetuximab: A systematic review

PURPOSE Radiotherapy plus cetuximab is an effective combination therapy for locally advanced head and neck squamous cell carcinoma. The aim of our study was to determine the frequency of skin toxicity in patients receiving the combined treatment. RESULTS Forty-eight studies were included in our analysis, for a total of 2152 patients. The mean rates of G3/G4 radiation dermatitis and acneiform rash were 32.5% (SD: 20.4; 95% CI: 28.5-36.5) and 13.4% (SD: 11.5; 95% CI: 11.2-15.6), respectively. The majority of studies referred to CTCAE scales for reporting both side effects (85.7% and 92.1%, respectively). Data on the management of skin toxicity were available in only 35.4% of the reviewed literature. CONCLUSIONS severe radiation dermatitis is a frequent side effect induced by the combination of radiotherapy and cetuximab in head and neck cancer. The lack of predictive biomarkers of toxicity hampers the possibilty to design preventive measures on a personalized basis.

Prognostic factors in patients with locally advanced head and neck cancer treated with concurrent radiochemotherapy

PurposeThis study was undertaken to evaluate the association of individual parameters and outcome in patients with unresectable locally advanced head and neck cancer treated with radiochemotherapy.Materials and methodsWe retrospectively reviewed data from 126 patients treated in our Institution between 1998 and 2010 for a locally advanced head and neck cancer. Sixteen individual parameters were evaluated for association with specific outcomes such as overall survival, persistence of disease, disease-specific survival and disease-free survival.ResultsSix factors influenced overall survival on Kaplan–Meier survival analysis and on univariate Cox regression analysis: smoking, body mass index, site, haemoglobin (Hb) nadir, total dose of radiotherapy and comorbidities. On a multivariate logistic model with stepwise selection, comorbidities, body mass index, total dose and site maintained significance. A significant association for persistence of disease was found with smoking, Hb nadir and site of cancer on univariate and multivariate analysis. Disease-free survival was correlated with performance status, Hb nadir and comorbidities using Kaplan–Meier survival analysis and on univariate Cox regression analysis. Only performance status maintained the significance on multivariate analysis. Disease-specific survival was correlated with five parameters: body mass index, site, Hb nadir, therapy interruption and total dose; on multivariate analysis, Hb nadir, therapy interruption and site maintained a statistically significant association.ConclusionsHb nadir during treatment, body mass index, smoking, stage, comorbidities and performance status are prognostic factors of outcome and response to radical treatment with radiochemotherapy.

Anti PD-L1 DUrvalumab combined with Cetuximab and RadiOtherapy in locally advanced squamous cell carcinoma of the head and neck: A phase I/II study (DUCRO)

Highlights • Head and neck squamous cell carcinoma is an immune suppressive malignancy.• Conventional intensification strategies didn’t provide any incremental benefit.• Inhibiting the PD-1/PD-L1 checkpoint may synergize with cetuximab and radiotherapy.

Elderly patients affected by head and neck squamous cell carcinoma unfit for standard curative treatment: Is de-intensified, hypofractionated radiotherapy a feasible strategy?

OBJECTIVES The aim of our work was to report on the clinical outcome of a moderately hyprofractionated radiotherapy regimen in elderly patients affected by head and neck squamous cell carcinoma (HNSCC). MATERIAL AND METHODS HNSCC aged ≥65 deemed unsuitable for curatively-intended concurrent chemo-radiotherapy or high-dose radiotherapy by clinical judgement were further evaluated with the Geriatric 8 (G8) questionnaire and Charlson comorbidity index (CCI). In case of a G8 score ≤14, a de-intensified radiation schedule of 40 Gy delivered in 16 fractions was prescribed. RESULTS Thirty-six patients were treated between 2011 and 2016. The median age of the cohort was 77.5 (range: 65-91 years) with a combined ECOG PS of 2-3 in 77.8% and CCI of ≥8 in 25% patients, respectively. At a median follow-up of 13 months (range 2-62 months), the 6-month and 1-year rates of loco-regional control and progression-free survival were 42%, 28% and 36% and 20%, respectively. At univariate analysis, log-rank test showed that age >75 years (p=0.036), worse PS (ECOG≥2; p=0.027), lower G8 score (<9; p=0.027) and PTV volume greater than 200 cc (p=0.038) had a significant correlation with PFS. The negative impact of the PTV volume on PFS was the only parameter confirmed in the multivariate analysis (HR 2.68; 95% CI: 1.24-5.81, p=0.013). No grade 4-5 toxicity was observed, while 13/36 patients (36%) had G3 acute side effects. CONCLUSION The hypofractionated radiation schedule evaluated provides clinical benefit with low toxicity in frail, elderly patients affected by locally advanced HNSCC.