Re-irradiation for head and neck squamous cell carcinoma

Introduction

Local recurrences after curative treatment have a potential for cure with salvage surgery or with re-irradiation.

Functional surgery for head and neck squamous cell carcinoma

Surgery for head and neck squamous cell carcinoma can alter speech, swallowing, and cosmoses. Recent tendency is to avoid mutilating surgery unless the tumour is aggressive or resistant to chemotherapy and or radiotherapy. Functional surgery is being widely employed, and for example it may vary between conventional partial surgery and endoscopic laser surgery for small sized vocal cord cancers. Various new reconstructive procedures have been developed to help early functional restoration. Loco-regional flaps can be used to replace gums and avoid dental extractions. Free flaps with micro-vascular anastomosis can be employed for immediate reconstruction of extensive surgical defects involving pharyngeal wall, tongue, mandible and mid-face to restore better function and cosmoses. Few recently developed techniques can be also employed in selected cases of laryngo-pharyngeal cancers to avoid permanent laryngeal mutilation. Another goal of functional surgery is to decrease the postoperative radiotherapy or chemo-radiotherapy sequelae, and obtain successful postoperative functional rehabilitation.     

CD44 as a stem cell marker in head and neck squamous cell carcinoma

In the recent past, evidence is increasing indicating the existence of a subpopulation of resistant tumor cells in head and neck squamous cell carcinoma (HNSCC) that cannot be eradicated by established antineoplastic treatments. These cancer stem cells (CSCs) have features of somatic stem cells such as selfrenewal, proliferation and differentiation. CD44+ cells in tumors of the head and neck are referred to as CSCs of HNSCC. Expression profiling of CD44 in 29 HNSCC tumors was performed by fluorescence microscopy. ELISA analysis was performed to detect concentration of soluble CD44 in the peripheral blood of 29 HNSCC patients and 11 healthy controls. Expression of CD44 was determined in all HNSCC tissue samples (n=29). In all samples a surface staining pattern was found. The concentration of CD44 in the peripheral blood of HNSCC patients was significantly higher compared to a healthy control group (mHNSCC =13.5 ± 0.5 ng/ ml; mCont = 9.3 ± 0.6 ng/ml; P=0.6 x 10(-12)). The role of CD44 as a marker for CSCs in HNSCC remains to be ascertained. Further experiments might reveal its role as a diagnostic and prognostic factor, and possibly as a therapeutic target.     

头颈部鳞癌术后辅助放化疗的研究现状

临床研究显示,术后放化疗能够提高头颈部鳞癌术后高危患者的治疗疗效.放疗实施时需根据原发肿瘤部位、临床分期、术后病理和术后影像学评估情况来确定照射靶区和剂量.目前临床上推荐放疗同步应用单药顺铂方案已经达成共识,而放疗同步联合其他化疗药物和(或)表皮生长因子受体(epidermal growth factor receptor,EGFR)单抗的疗效则仍不确定.人乳头状瘤病毒(human papillomavirus,HPV)阳性口咽癌具有独特的生物学特性,其术后放化疗适应证和辅助放化疗的治疗模式至今仍不明确,值得深入研究.     

HLA and MICA associations with head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is a very aggressive tumour arising from the epithelial lining of the upper aerodigestive tract. The precise mechanisms involved in the pathogenesis of HNSCC have not been elucidated. Previous studies observed aberrant HLA expression patterns on HNSCC tumour cells and this study focused on the allelic polymorphism of HLA genes and the MHC class I chain related gene A (MICA) and HNSCC. We investigated whether associations with HLA and/or MIC alleles or haplotypes are involved in the pathogenesis of HNSCC and could explain the observed HLA expression patterns. Patients and controls were typed for HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 with sequence specific priming (SSP), supplemented with sequencing based typing (SBT). MICA allelic polymorphism was included and MICA allele assignment was based upon the combination of high resolution SBT of exons 2-4 in combination with repeat analysis and nucleotide polymorphism of exon 5. HLA-B *35 (p=0.014, OR=0.31) and HLA-B *40 (p=0.013, OR=2.9) were significantly associated in respectively the metastasized patients and the oral cavity patients. In addition, the HLA-B *40-DRB1 *13 haplotype (p=0.016, OR=4.1) was more often observed in the oral cavity patient group. The biological significance of the prevalence of specific HLA haplotypes in patients with oral cavity HNSCC and metastasizing HNSCC requires further investigation.     

Targeted therapy for squamous cell carcinoma of the head and neck

Targeted agents have emerged as novel drugs in the oncology field based on our understanding of the biology of individual malignancies, and have had a promising impact in several tumors. Squamous cell carcinoma of the head and neck (SCCHN) is a common disease with little progress made in survival over the past few decades. SCCHN is characterized by overexpression of the epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF), both of which appear to have a prognostic value. Hence these receptors and their downstream pathways make attractive therapeutic targets. This review discusses targeted therapies currently being evaluated for their role in squamous cell carcinoma of the head and neck.     

头颈部鳞状细胞癌靶向治疗进展

每年全世界大约有65万例新的头颈癌病例出现,其中绝大多数是头颈部鳞状细胞癌.晚期头颈部鳞状细胞癌的治疗需要综合治疗,尽管放化疗及手术治疗手段在不断发展,但是预后仍不理想且具有一定的毒副反应.靶向治疗是目前治疗研究头颈部鳞癌的热点,其在针对头颈部鳞癌的治疗特别是对局部晚期或复发/转移性头颈部鳞癌治疗中展现出了希望.本文综...     

CD4+ T helper responses in squamous cell carcinoma of the head and neck

Anti-tumor immunity plays an important role in the development of and protection from malignancy. However, there is a lack of information regarding induction of CD4+ T helper responses in patients with squamous cell carcinoma (SCCHN). To explore anti-tumor immune responses against SCCHN, a permanent cell line, Gun-1 was established from a squamous cell carcinoma of the hypopharynx. In addition to its characterization, we performed mixed lymphocyte-tumor cell cultures (MLTC) using peripheral blood lymphocytes and autologous tumor cells. Furthermore, T cell responses to wild type (wt) p53-derived peptides were assessed. Gun-1 cells overexpressed p53 and were negative for HLA-A2 expression. No tumor-specific or wt p53-specific CD8+ CTL lines could be established from peripheral blood mononuclear cells (PBMCs) of this patient. Autologous tumor-specific HLA-DR-restricted CD4+ T helper clone was obtained by limiting dilutions using bulk populations from MLTC. This clone produced IFN-gamma but not IL-5 in response to autologous tumor cells. In addition, CD4+ T cells were generated from the patient's PBMCs which responded to two HLA-DP5-restricted wt p53-derived peptides. Our results suggest that the immune cells specific for autologous tumor as well as wt p53-derived epitopes are present in the peripheral circulation of this cancer patient. However, helper-type CD4+ T lymphocytes represent the predominant anti-tumor response.     

Docetaxel and squamous cell carcinoma of the head and neck

Chemotherapy in head and neck carcinoma is used as palliative treatment but also as induction treatment or combined treatment with concurrent radiation therapy. Platinum and 5-fluorouracil are the most commonly used cytotoxic agents. Docetaxel is an active drug for treating head and neck carcinoma. For patients with recurrent or metastatic disease, docetaxel could be used either as a second line chemotherapy or a first line for patients who received previously platinum or 5FU. In combination with platinum and 5FU, used as induction chemotherapy the TPF regimen is a very active treatment with an overall response rate of 85 to 90% with a manageable acute toxicity rate. This approach is under investigation in terms of ability to obtain more larynx preservation compared to the standard approach with platinum and 5FU. Docetaxel is a radiosensitizer. Concurrent radiochemotherapy using docetaxel alone is feasible, Trials are needed to define the optimal regimen for combining radiation, platinum and docetaxel.     

Human papillomavirus 16 and head and neck squamous cell carcinoma

Evidence suggests that human papillomavirus (HPV)16 seropositivity reflects past HPV16 exposure and is associated with risk for head and neck squamous cell carcinoma (HNSCC). Our objectives were to test the hypothesis that HPV16 seropositivity is associated with risk for HNSCC, to correlate HPV16 seropositivity with HPV16 tumor DNA, and to correlate HPV16 seropositivity and HPV16 DNA with sexual history and patient survival. In a case-control study of approximately 1,000 individuals, we assessed serology to the HPV16 L1 protein and in cases only, assayed tumors for HPV16 DNA. HPV16 seropositivity was associated with 1.5- and 6-fold risks for tumors of the oral cavity and pharynx, respectively. There was a dose response trend for HPV16 titer and increasing risk of HNSCC (p < 0.0001) and HPV16 tumor DNA (p < 0.0001). In cases, HPV16 DNA and seropositivity were significantly associated with sexual activity; odds ratios (ORs) of 12.8 and 3.7 were observed for more than 10 oral sexual partners and ORs of 4.5 and 3.2 were associated with a high number of lifetime sexual partners, respectively. Finally, HPV16 seropositivity and HPV16 tumor DNA were associated with hazard ratios of 0.4 and 0.5, respectively, indicating better survival for HPV positive individuals. HPV16 seropositivity was associated with risk for HNSCC, with greatest risk for pharyngeal cancer. We observed dose response relationships between serology titer and both risk for HNSCC and HPV16 tumor DNA. In cases, HPV16 tumor DNA and positive serology were associated with sexual history and improved disease free survival.     

Plasmacytoid dendritic cell subpopulations in head and neck squamous cell carcinoma

Human plasmacytoid dendritic cells (PDCs) are present in solid tumor tissue and metastatic cervical lymph nodes (CLN) in head and neck squamous cell carcinoma (HNSCC). We recently showed that classical PDC functions are heavily disturbed in the tumor microenvironment. In this study we present a new approach to the subject by introducing 3 PDC subsets in HNSCC, characterized by the surface markers CD25, CD56 and CD203c. The first subset, positive for CD25, is significantly induced by HNSCC in?vitro and present in metastatic lymph nodes in?vivo. This subset can be phenotypically subdivided into matured cells and into a group expressing early T cell markers. Functionally this subgroup is associated with the secretion of IL-8. The second subset, positive for CD56, constitutes 4-5% of all PDCs and is significantly down-regulated by HNSCC. Furthermore, this population sporadically expresses perforin/granzyme B and is absent in metastatic lymph nodes. The third subset, positive for the basophile marker CD203c, is inducible by crosslinking BDCA-2 in the presence of HNSCC and IL-4. Future studies will have to clarify the in vivo relevance of the different PDC subsets in HNSCC.     

头颈部鳞癌放射治疗现状与展望

在过去的20年,头颈部鳞癌（squamous cell careinoma of the head and neck,SCCHN）的手术、放疗和化疗等都有了重大进展。手术治疗从扩大根治转向保留器官或器官功能保护,如半喉切除、喉重建和激光治疗。适形调强放疗（intensity—modulated radiationtherapy,IMRT）和改变分割照射方法则使放疗的耐受性和临床疗效得到了提高。此外,随着有效化疗药物的出现,其在局部晚期SCCHN综合治疗中的作用受到越来越多的重视。     

Human papilloma virus integration sites and genomic signatures in head and neck squamous cell carcinoma

A prevalence of around 26% of human papillomavirus (HPV) in head and neck squamous cell carcinoma (HNSCC) has been previously reported. HPV induced oncogenesis mainly involving E6 and E7 viral oncoproteins. In some cases, HPV viral DNA has been detected to integrate with the host genome and possibly contributes to carcinogenesis by affecting the gene expression. We retrospectively assessed HPV integration sites and signatures in 80 HPV positive patients with HNSCC, by using a double capture‐HPV method followed by next‐generation Sequencing. We detected HPV16 in 90% of the analyzed cohort and confirmed five previously described mechanistic signatures of HPV integration [episomal (EPI), integrated in a truncated form revealing two HPV‐chromosomal junctions colinear (2J‐COL) or nonlinear (2J‐NL), multiple hybrid junctions clustering in a single chromosomal region (MJ‐CL) or scattered over different chromosomal regions (MJ‐SC) of the human genome]. Our results suggested that HPV remained episomal in 38.8% of the cases or was integrated/mixed in the remaining 61.2% of patients with HNSCC. We showed a lack of association of HPV genomic signatures to tumour and patient characteristics, as well as patient survival. Similar to other HPV associated cancers, low HPV copy number was associated with worse prognosis. We identified 267 HPV‐human junctions scattered on most chromosomes. Remarkably, we observed four recurrent integration regions: PDL1/PDL2/PLGRKT (8.2%), MYC/PVT1 (6.1%), MACROD2 (4.1%) and KLF5/KLF12 regions (4.1%). We detected the overexpression of PDL1 and MYC upon integration by gene expression analysis. In conclusion, we identified recurrent targeting of several cancer genes such as PDL1 and MYC upon HPV integration, suggesting a role of altered gene expression by HPV integration during HNSCC carcinogenesis.