Effect of lymphoid volume irradiation on radiation-induced lymphopenia in head and neck cancers.

PURPOSE: Radiotherapy induces significant and prolonged lymphopenia in head and neck cancer patients with poorer outcomes and reduced survival. Irradiated volumes may be correlated with lymphopenia with a potential impact on immunotherapy efficacy. We assessed associations between volumes treated with radiotherapy and the nadir of the lymphocyte count in patients with head and neck cancer. MATERIALS AND METHODS: We conducted a monocentric retrospective study in patients with head and neck cancer treated with radiation. Univariate analysis used regression analysis to model nadir lymphocyte count and radiotherapy volumes; multivariate analysis then modelled factors associated with nadir lymphocyte count. RESULTS: Of the 77 included patients, 97% presented lymphopenia during radiotherapy with an average nadir of 431 cells/mm3 at a median of 40 days after the beginning of treatment. The volume of high-risk radiotherapy and gross tumour volume were correlated with nadir lymphocyte count with a Spearman coefficient of -0.267 (P=0.019) and -0.387 (P=0.001), respectively. After multivariate linear regression, high-risk radiotherapy was significantly associated with nadir lymphocyte count with a regression coefficient of -0.32 (per cubic centimetre) [95% CI=-0.60; -0.03] (P=0.028). CONCLUSION: High-risk radiotherapy was significantly associated with nadir lymphocyte count in patients with head and neck cancer treated with radiation. Sparing lymphoid volumes from irradiation by elective nodal irradiation or proton therapy may limit lymphopenia and needs to be investigated in combination with immunotherapy.

Postoperative radiotherapy after flap reconstructive surgery in patients with head and neck cancer: A retrospective monocentric study with flap delineation to assess toxicity and relapse.

PURPOSE: Flaps are increasingly used during reconstructive surgery of head and neck cancers to improve functional outcomes. There are no guidelines as to whether the whole flap or its anastomotic border should be included in the primary tumour target volume of postoperative radiotherapy to prevent local relapses. Relapse and toxicity rates can increase substantially if the whole flap received full dose. Our aim was to determine whether flaps were included in the primary tumour target volume and to report the patterns of relapse and toxicity. MATERIALS AND METHODS: Consecutive patients in 2014 through 2016, with or without a flap, receiving postoperative radiotherapy were selected in a retrospective monocentric control study. Flaps were homogenously delineated blind to treating radiation oncologists using a flap-specific atlas. Tumour recurrence, acute and late toxicity were evaluated using univariate and propensity score analyses. RESULTS: A hundred patients were included; 54 with a flap. Median flap volume included in the tumour volume was 80.9%. Twelve patients experienced local recurrences: six with a flap, among whom two within their flap (3.7%). Patients with flaps had larger median tumour volumes to be irradiated (25cm3 versus 58cm3, p<0.001) and higher acute/late toxicity rates (p<0.001) even after adjustment on biases (more advanced T stage, oral cavity, active smoking in patients with flaps). Locoregional recurrence and survival rates were similar between patients with/without a flap. CONCLUSION: Recurrences within a flap were rare in this series when including the whole flap body in the 60Gy-clinical target volume but inclusion of the flap in the primary tumour target volume increased toxicity. Multicentric studies are warranted.

Flap delineation guidelines in postoperative head and neck radiation therapy for head and neck cancers.

INTRODUCTION: Reconstructive surgery in head and neck cancers frequently involves the use of autologous flaps to improve functional outcomes. However, the literature suggests that postoperative radiotherapy deteriorates functional outcomes due to flap atrophy and fibrosis. Data on patterns of relapse after postoperative radiotherapy with a flap are lacking, resulting in heterogenous delineation of postoperative clinical target volumes (CTV). Flap delineation is unusual in routine practice and there are no guidelines on how to delineate flaps. Therefore, we aim to propose a guideline for flap delineation in head and neck cancers to assess dose-effects more accurately with respect to flaps. MATERIAL AND METHODS: Common flaps were selected. They were delineated by radiation oncologists and head and neck surgeons based on operative reports, on contrast-enhanced planning CTs and checked by a radiologist. Each flap was divided into its vascular pedicle and its soft tissue components (fat, fascia/ muscle, skin, bone). RESULTS: Delineation (body and pedicle) of Facial Artery Musculo-Mucosal, pectoralis, radial forearm, anterolateral thigh, fibula and scapula flaps was performed. Based on information provided in operative reports, i.e. tissue components, size and location, flaps can be identified. The various tissue components of each flap can be individualized to facilitate the delineation. CONCLUSION: This atlas could serve as a guide for the delineation of flaps and may serve to conduct studies evaluating dose-effects, geometric patterns of failure or functional outcomes after reconstructive surgery. Changes in postoperative CTV definitions might be needed to improve risk/benefit ratio in the future based on surgery-induced changes.

Routine feasibility of postoperative chemoradiotherapy in head and neck squamous cell carcinoma at high risk of recurrence.

OBJECTIVE: To assess the feasibility in routine practice of postoperative chemoradiotherapy in head and neck squamous cell carcinoma (HNSCC) at high risk of recurrence. METHOD: A single-center retrospective study recruited all patients receiving postoperative cisplatin chemoradiotherapy for HNSCC at high risk of recurrence. The main endpoints were the rate of complete postoperative chemoradiotherapy and the impact of various clinical factors. Secondary endpoints comprised the impact of completion of therapy on survival and on acute and late toxicity. RESULTS: One hundred and six patients were included. 24.5% showed severe comorbidity. Chemoradiotherapy was complete in 61 patients (57.5%). Radiation therapy was interrupted for >3 days in 16 patients (15.1%). The 3rd concomitant cisplatin course could not be implemented in 34 patients (32.1%). Low pre-treatment glomerular filtration rate was significantly associated (p=0.003) with treatment interruption; >5% weight-loss during treatment showed suggestive association (p=0.026). Completion of treatment was not associated with any significant difference in overall survival (p=0.441) or progression-free survival (p=0.81). 14.9% of patients showed post-treatment kidney failure; there were 10 cases of osteoradionecrosis (9.4%). CONCLUSION: The rate of complete postoperative chemoradiotherapy was comparable to that reported in clinical trials, despite frequent comorbidity and poor nutritional status. Early nutritional support is a key factor for treatment under optimal conditions.

Impact of locoregional irradiation in patients with upfront metastatic head and neck squamous cell carcinoma.

OBJECTIVE: To evaluate the frequency of use, modalities and potential interest of locoregional irradiation (LRT) in patients with upfront metastatic head and neck squamous cell carcinoma (HNSCC). METHODS: Retrospective multicentric study. Were included all patients presenting an upfront metastatic HNSCC treated by platin-5FU- cetuximab based regimen, from 2008 to 2016. Patients with past history of cervical irradiation or HNSCC within the 5 years before metastasis diagnosis were excluded. RESULTS: 65 patients were included. 25 patients (38%) presented a response or stable disease with chemotherapy. Forty-one patients (63%) underwent a locoregional irradiation: 5 patients before chemotherapy (upfront RT), 13 patients with stable disease or response after chemotherapy (consolidation RT), and 23 patients with progressive disease. Median overall survival (OS) was 11.6 months, median progression free survival was 7.9 months. OS was significantly improved for patients who underwent LRT (median OS 16.1 vs 7.5 months, p < 0.01). Among patients who received LRT, OS trended to be better if LRT was performed as consolidation RT compared to upfront RT (median OS of 22.1 vs 15.5 months, p = 0.11). Among patients with stable disease or response after chemotherapy, there was a non-significant better OS for the 13 patients treated by LRT (median OS 22.1 vs 11.8 months, p = 0.21)). Radical dose was not associated with better locoregional control compared to palliative dose (p = 0.37). CONCLUSION: LRT is frequently performed during management of upfront metastatic HNSCC and associated with better OS. Non-progressive disease after firs-line chemotherapy seems a good way to select patients who would benefit from radical LRT.

Platinum rechallenge in recurrent head and neck squamous cell carcinoma after primary chemoradiation.

OBJECTIVE: To evaluate platinum rechallenge efficacy and tolerance in patients presenting recurrent head and neck squamous cell carcinoma (HNSCC) after platinum-based chemoradiation. MATERIALS AND METHODS: We retrospectively included all patients treated from 2007 to 2016 by platinum-based polychemotherapy for recurrence of HNSCC previously treated by primary or postsurgical platinum-based chemoradiation. The primary end-point was disease control rate (DCR) on platinum rechallenge. RESULTS: Forty-five patients were included. Median disease-free interval (DFI) after chemoradiation was 5.7 months. DCR on platinum rechallenge was 40%. Progression-free survival at recurrence was 3.7 months and overall survival 5.0 months. DCR in patients with recurrence within 6 months of chemoradiotherapy was 47.8%. DFI>4.5 months was associated with better DCR: 28.5% versus 54.8%; P=0.0311. CONCLUSION: Platinum rechallenge provided good DCR in recurrent HNSCC after chemoradiation.

[Re-irradiation of head and neck cancers: Target volumes, technical evolutions and prospects]. / Réirradiation des tumeurs de la tête et du cou : volumes cibles, évolutions techniques et perspectives.

Malignant tumors of the head and neck have a predominantly regional recurrence pattern, with most deaths resulting from this progression. Optimization of re-radiation in recurrence setting is a major objective for these patients. Extensive research has been carried out with the PubMed search engine to find publications dealing with this topic. The first attempts to reirradiate the ORL sphere date back to the 1980s and the first to be performed by intensity modulation conformational radiotherapy (IMRT) date back to the late 1990s. Compared to 3 dimensional conformal radiotherapy, IMRT improves clinical outcomes and reduces toxicity. In IMRT series, associated or not with concomitant chemotherapy, the locoregional control obtained at 2 years was of the order of 45 to 65% and the overall survival of 15 to 60%, depending on predictive factors. Grade 3 acute toxicity occurred on the order of 10 to 30% and late-grade 3 toxicity on the order of 15 to 50%. In a selected population with low volumes tumors, stereotactic re-irradiation at a minimum dose of 35Gy obtained outcome comparable to IMRT. Re-irradiation of head and neck tumors by proton therapy is rare. The toxicity rate appears to be lower than that usually seen after photon therapy. However, we do not have a long follow-up. This technique therefore remains reserved for search protocols and represents a future perspective in these situations.

Exclusive radiotherapy for stage T1-T2N0M0 lanryngeal cancer: retrospective study of 59 patients at CFB and CHU de Caen.

OBJECTIVE: Study of patients with stage T1N0M0 or T2N0M0 glottic cancer treated by exclusive radiotherapy and comparison of the survival and functional results of this series with those of the literature. METHOD: Retrospective study of stage T1N0M0 or T2N0M0 glottic cancers diagnosed between 1st January 2000 and 31st December 2010 and treated by exclusive radiotherapy. Evaluation of survival, recurrence and larynx preservation rates. STUDY CENTRES: CLCC François-Baclesse and CHU de Caen. PATIENTS: Fifty-nine patients (53 men and sixwomen) treated for glottic cancer (57 squamous cell carcinomas, two verrucous carcinomas) comprising 51 T1N0M0 and eight T2N0M0 tumours. Treatment with exclusive radiotherapy (mean dose of 70 Grays limited to the thyroid cartilage for 57 patients, with lymph node irradiation for two patients). RESULTS: In this series, five (9.8%) patients with stage T1N0M0 glottic cancer and three patients (37.5%) with stage T2N0M0 glottic cancer relapsed, corresponding to a global recurrence rate of 13.6%. Three of the eight recurrences involved lymph nodes exclusively (N), two patients relapsed exclusively at the primary tumour site (T) and three patients presented local and lymph node recurrence (T and N). Treatment consisted of salvage total laryngectomy with bilateral cervical lymph node dissection in three cases, bilateral cervical lymph node dissection and sensitized radiotherapy in two cases, exclusive chemotherapy in one case, cervical lymph node dissection and cervical radiotherapy in one case. The last patient with recurrence died prior to salvage therapy. The larynx preservation rate was 94.9%. CONCLUSION: In comparison with the literature, treatment of stage T1-T2N0M0 glottic cancer by exclusive radiotherapy gives very good results, with a larynx preservation rate of 95%.

Biochemical and localization analyses of putative type III secretion translocator proteins CopB and CopB2 of Chlamydia trachomatis reveal significant distinctions.

Chlamydia spp. are among the many pathogenic Gram-negative bacteria that employ a type III secretion system (T3SS) to overcome host defenses and exploit available resources. Significant progress has been made in elucidating contributions of T3S to the pathogenesis of these medically important, obligate intracellular parasites, yet important questions remain. Chief among these is how secreted effector proteins traverse eukaryotic membranes to gain access to the host cytosol. Due to a complex developmental cycle, it is possible that chlamydiae utilize a different complement of proteins to accomplish translocation at different stages of development. We investigated this possibility by extending the characterization of C. trachomatis CopB and CopB2. CopB is detected early during infection but is depleted and not detected again until about 20 h postinfection. In contrast, CopB2 was detectible throughout development. CopB is associated with the inclusion membrane. Biochemical and ectopic expression analyses were consistent with peripheral association of CopB2 with inclusion membranes. This interaction correlated with development and required both chlamydial de novo protein synthesis and T3SS activity. Collectively, our data indicate that it is unlikely that CopB serves as the sole chlamydial translocation pore and that CopB2 is capable of association with the inclusion membrane.

Treatment of Chlamydia trachomatis with a small molecule inhibitor of the Yersinia type III secretion system disrupts progression of the chlamydial developmental cycle.

The obligate intracellular bacterium Chlamydia trachomatis possesses a biphasic developmental cycle that is manifested by differentiation of infectious, metabolically inert elementary bodies (EBs) to larger, metabolically active reticulate bodies (RBs). The cycle is completed by asynchronous differentiation of dividing RBs back to a population of dormant EBs that can initiate further rounds of infection upon lysis of the host cell. Chlamydiae express a type III secretion system (T3SS) that is presumably employed to establish and maintain the permissive intracellular niche by secretion of anti-host proteins. We hypothesize that T3SS activity is essential for chlamydial development and pathogenesis. However, the lack of a genetic system has confounded efforts to establish any role of the T3SS. We therefore employed the small molecule Yersinia T3SS inhibitor N'-(3,5-dibromo-2-hydroxybenzylidene)-4-nitrobenzohydrazide, designated compound 1 (C1), to examine the interdependence of the chlamydial T3SS and development. C1 treatment inhibited C. trachomatis but not T4SS-expressing Coxiella burnetii development in a dose-dependent manner. Although chlamydiae remained viable and metabolically active, they failed to divide significantly and RB to EB differentiation was inhibited. These effects occurred in the absence of host cell cytotoxicity and were reversible by washing out C1. We further demonstrate that secretion of T3S substrates is perturbed in C1-treated chlamydial cultures. We have therefore provided evidence that C1 can inhibit C. trachomatis development and T3SS activity and present a model in which progression of the C. trachomatis developmental cycle requires a fully functional T3SS.

Modulation of clonogenicity, growth, and radiosensitivity of three human epidermoid tumor cell lines by a fibroblastic environment.

PURPOSE: To develop a model vitro system to examine the influence of fibroblasts on the growth and survival of human tumor cells after exposure to ionizing radiation. METHODS AND MATERIALS: The cell system of three epidermoid carcinoma cell lines derived from head and neck tumors having differing growth potentials and intrinsic radiosensitivities, as well as a low passage skin fibroblast strain from a normal human donor. The tumor cells were seeded for five days prior to exposure to radiation: (a) in the presence of different numbers of fibroblasts, (b) in conditioned medium from stationary fibroblast cultures, and (c) on an extracted fibroblastic matrix. RESULTS: When grown with fibroblasts, all three tumor cell lines showed increased clonogenicity and increased radioresistance. The radioprotective effect was maximal at a density of approximately 10(5) fibroblasts/100 mm Petri dish, and was greatest in the intrinsically radiosensitive tumor cell line. On the other hand, the effects of incubation with conditioned medium or on a fibroblastic matrix varied among the tumor cell lines. Thus, the protective effect afforded by coculture with fibroblasts must involve several cellular factors related to the fibroblast itself. CONCLUSIONS: These observations emphasize the importance of cultural conditions on the apparent radiosensitivity of human tumor cell lines, and suggest that the fibroblastic connective tissue enveloping the malignant cells should be considered when the aim is to establish a radiopredictive assay from surgical tumor fragments.

[Brachytherapy in cancer of the penis]. / La curiethérapie des cancers du pénis.

Brachytherapy can play an essential role in the conservative treatment of penile cancer limited to the glans. This treatment is usually performed using hypodermic needles with templates which are subsequently loaded with iridium wires. Various studies, particularly French reports, show a local control rate of 80%, penis preservation in 75% of cases and a specific survival rate of 60%.