Current concepts of management in radiotherapy for head and neck squamous-cell cancer

Evaluation of the Effects of Radiation Therapy on Muscle Contractibility and Skin Healing: An Experimental Study of the Cancer Treatment Implications

BACKGROUND

Radiotherapy can affect healthy cells, resulting in side effects. This study aimed to assess the impact of radiotherapy on soft tissue in surgical wounds in rats.

METHODS

The animals were divided into four groups: control (S) group without irradiation, immediate irradiation (S-IIr) group receiving irradiation right after surgery, late irradiation (S-LIr) group receiving irradiation four weeks after surgery, and early irradiation (Ir-S) group receiving irradiation before surgery. The irradiated groups underwent two fractional stages of 15 Gy. Muscle contractibility (EMG) was evaluated at two different time points, and after 2 and 7 weeks, the animals were euthanized for histological analysis of the muscles and skin.

RESULTS

There was no significant difference between the EMG1 and EMG2 values of the S and S-LIr groups, but both S-IIr and Ir-S groups exhibited a statistically significant difference. The S group demonstrated a larger diameter of muscle fiber compared to other groups, showing a significant difference. In terms of skin analysis, the S-IIr group had the least inflammatory infiltrate and the highest amount of red fibers, differing significantly from the other groups.

CONCLUSIONS

Regardless of the duration, radiotherapy was found to have effects on the surrounding soft tissues, as concluded by this study.

Brazilian organic propolis for prevention and treatment of radiation-related oral acute toxicities in head and neck cancer patients: A double-blind randomized clinical trial

Background: Oral mucositis (OM) is one of the most important acute toxicities from radiotherapy (RT) in head and neck cancer patients and can impair oncologic treatment. Dysphagia, dysgeusia, pain, and oral candidiasis are other common toxicities. Brazilian Organic Propolis (BOP) is a recently described propolis variant and BOP types 4 and 6 have shown important antioxidant, anti-inflammatory, and antifungal properties.

Purpose: To investigate the use of BOP as a preventive and/or complementary therapeutic option for radiotherapy-induced oral mucositis, dysphagia, dysgeusia, pain, and oral candidiasis. Additionally, proinflammatory cytokines were assessed to investigate their anti-inflammatory role.

Methods: Sixty patients were included in this randomized, double-blind, controlled clinical trial. Patients were randomized to receive either aqueous suspension of a BOP or placebo throughout RT. Also, all patients underwent low-level laser therapy as routine oral care. OM, dysphagia, and dysgeusia were assessed weekly according to WHO and NCI scales. Pain-related to OM was assessed according to a Visual Analog Scale and the presence or absence of oral candidiasis was checked by intraoral examination. Protein levels of TNF-α and IL-1β from oral mucosa were assessed by ELISA.

Results: Patients in the propolis group had a lower mean score of OM, dysphagia, dysgeusia, and most patients reported moderate pain. Fewer patients developed oral candidiasis in the propolis group, and the number of episodes was lower among patients that used BOP (p < 0.05). In addition, the BOP group presented significantly lower levels of IL-1β since the beginning of treatment when compared with placebo patients (p < 0.05) and a lower level of TNF-α at the end of treatment (p < 0.001).

Conclusion: Topic use of BOP reduced TNF-α and IL-1β levels, oral candidiasis episodes, and seems to be a useful complementary option for the prevention and treatment of the main acute oral toxicities of RT.

Clinical Trial Registration:http://www.ensaiosclinicos.gov.br/rg/RBR-9f8c78/, identifier RBR-9f8c78

Combination Treatment of TRPV4 Agonist with Cisplatin Promotes Vessel Normalization in an Animal Model of Oral Squamous Cell Carcinoma

Background and Objectives: Oral squamous cell carcinoma (OSCC) is the sixth most common malignancy in the world. Transient receptor potential vanilloid 4 (TRPV4) channel has been shown to be involved in angiogenesis in multiple types of tumors. However, not much is known about TRPV4′s involvement in OSCC. Thus, in this study, we investigate the effect of administering a TRPV4 agonist on angiogenesis in OSCC. Materials and Methods: Thirty-six Sprague Dawley (SD) rats were used in this study. 4-nitroquinoline 1-oxide (4NQO) was used to induce OSCC. Cisplatin (an anticancer drug), and GSK1016790A (an agonist for TRPV4) was used in this study. Immunohistochemistry was employed to examine the TRPV4 expression. An RT2 Profiler PCR Array was performed for gene expression analysis of TRPV4, vascular growth factors that correspond directly with angiogenesis, such as angiopoietin (Ang-1 and Ang-2), and tyrosine kinase (Tie-1 and Tie-2) receptors. Tumor vessel maturity was assessed by microvessel density and microvessel-pericyte-coverage index. Results: RT2 profiler PCR array showed significant elevated levels of Ang-1 (2.1-fold change; p < 0.05) and Tie-2 (4.5-fold change; p < 0.05) in OSCC following the administration of a combination of GSK1016790A and cisplatin. Additionally, the combination treatment significantly reduced the microvessel density (p < 0.01) and significantly increased the percentage of microvessels covered with pericytes (p < 0.01) in OSCC. Furthermore, tumor size was significantly reduced (p < 0.05) in rats that received cisplatin alone. The combination treatment also greatly reduced the tumor size; however, the data were not statistically significant. Conclusions: The findings suggest that combining a TRPV4 agonist with cisplatin for treatment of OSCC promote vessels normalization via modulation of Ang-1/Tie-2 pathway.

TNFα Signaling Is Increased in Progressing Oral Potentially Malignant Disorders and Regulates Malignant Transformation in an Oral Carcinogenesis Model

Oral carcinogenesis represents a multi-stage process which encompasses several genetic and molecular changes that promote the progression of oral potentially malignant disorders (OPMDs) to oral squamous cell carcinomas (OSCCs). A better understanding of critical pathways governing the progression of OMPDs to OSCCs is critical to improve oncologic outcomes in the future. Previous studies have identified an important role of tumor necrosis factor α (TNFα) and TNF receptor 1 (TNFR1) in the invasiveness of oral cancer cell lines. Here, we investigate the expression of TNFα and TNFR1 in human OPMDs that progress to OSCC compared to non-progressing OPMDs utilizing fluorescent immunohistochemistry (FIHC) to show increased TNFα/TNFR1 expression in progressing OPMDs. In order to interrogate the TNFα/TNFR1 signaling pathway, we utilized a 4-nitroquinoline 1-oxide (4-NQO) mouse model of oral carcinogenesis to demonstrate that TNFα/TNFR1 expression is upregulated in 4-NQO-induced OSCCs. TNFα neutralization decreased serum cytokines, inhibited the development of invasive lesions and reduced tumor-associated neutrophils in vivo. Combined, this data supports the role of TNFα in oral malignant transformation, suggesting that critical immunoregulatory events occur downstream of TNFR1 leading to malignant transformation. Our results advance the understanding of the mechanisms governing OSCC invasion and may serve as a basis for alternative diagnostic and therapeutic approaches to OPMDs and OSCC management.

Upregulation of Circular RNA circATRNL1 to Sensitize Oral Squamous Cell Carcinoma to Irradiation

Accumulating evidence has demonstrated that circular RNAs (circRNAs) play important roles in regulating gene expression involved in tumor development. However, the role of circRNAs in modulating the radiosensitivity of oral squamous cell carcinoma (OSCC) and its potential mechanisms have not been documented. We performed high-throughput RNA sequencing (RNA-seq) to investigate the circRNA expression profile in OSCC patients and discovered that the circATRNL1 expression was significantly downregulated and closely related to tumor progression. The circATRNL1 was structurally validated via Sanger sequencing, RNase R treatment, and specific convergent and divergent primer amplification. Importantly, the expression levels of circATRNL1 decreased after irradiation treatment, and upregulation of circATRNL1 enhanced the radiosensitivity of OSCC through suppressing proliferation and the colony survival fraction, inducing apoptosis and cell-cycle arrest. Moreover, we observed that circATRNL1 could directly bind to microRNA-23a-3p (miR-23a-3p) and relieve inhibition for the target gene PTEN. In addition, the tumor radiosensitivity-promoting effect of circATRNL1 overexpression was blocked by miR-23a-3p in OSCC. Further experiments also showed that PTEN can reverse the inhibitory effect of OSCC radiosensitivity triggered by miR-23a-3p. We concluded that circANTRL1 may function as the sponge of miR-23a-3p to promote PTEN expression and eventually contributes to OSCC radiosensitivity enhancement. This study indicates that circANTRL1 may be a novel therapeutic target to improve the efficiency of radiotherapy in OSCC.

Laryngeal chondronecrosis after radiation therapy in a dog

A 5-year-old pug presented with a soft tissue swelling on the ventral neck and moderate stridor with associated respiratory effort. This patient received hypofractionated radiotherapy for metastatic upper lip mast cell tumour and to the submandibular lymph nodes 6 months before presentation. Oral examination showed moderate elongation of the soft palate, stage III laryngeal collapse with only the right laryngeal saccule mildly everted and exuberant pale epiglottal and left pharyngeal mucosa. Staphylectomy, resection of the epiglottal mucosa and left arytenoid lateralisation were performed. One day after surgery, temporary tracheostomy was performed after respiratory distress due to the severe laryngeal and pharyngeal oedema. A third oral exam showed pale and redundant caudal pharyngeal mucosa obstructing the rima glottis, soft and collapsible arytenoid cartilage with pale mucosa and bilateral everted laryngeal saccules. Permanent tracheostomy was elected and laryngeal cartilage biopsies were taken. Histologic diagnosis showed cartilage necrosis and abundant tissue oedema. The patient was euthanased 1 week later.

Doxorubicin combined with low intensity ultrasound suppresses the growth of oral squamous cell carcinoma in culture and in xenografts

Background

Oral squamous cell carcinoma (OSCC) invades surrounding tissues by upregulating matrix metalloproteinases (MMPs) -2 and −9, which causes over-expression of the Hedgehog signaling proteins Shh and Gli-1 and degradation of the extracellular matrix, thereby creating a “highway” for tumor invasion. We explored the potential of low intensity ultrasound (LIUS) and doxorubicin (DOX) to inhibit the formation of this “highway”.

Methods

MTT assays were used to examine OSCC cell viability after exposure to LIUS and DOX. The cell morphological changes and ultrastructure were detected by scanning electron microscopy and transmission electron microscopy. Endogenous autophagy-associated proteins were analyzed by immunofluorescent staining and western blotting. Cell migration and invasion abilities were evaluated by Transwell assays. Collagen fiber changes were evaluated by Masson’s trichrome staining. Invasion-associated proteins were analyzed by immunohistochemistry and western blotting.

Results

LIUS of 1 W/cm² increased the in vitro DOX uptake into OSCC by nearly 3-fold in three different cell lines and induced transient autophagic vacuoles on the cell surface. The combination of LIUS and 0.2 μg/ml DOX inhibited tumor cell viability and invasion, promoted tumor stromal collagen deposition, and prolonged the survival of mice. This combination also down-regulated MMP-2, MMP-9, Shh and Gli-1 in tumor xenografts. Collagen fiber expression was negatively correlated with the expression of these proteins in human OSCC samples.

Conclusions

Our findings suggest that effective low dosages of DOX in combination with LIUS can inhibit cell proliferation, migration and invasion, which might be through MMP-2/9 production mediated by the Hedgehog signaling pathway.

Electronic supplementary material

The online version of this article (10.1186/s13046-017-0633-y) contains supplementary material, which is available to authorized users.

Effect of intratumoral abscess/necrosis on the outcome for head and neck cancer patients treated by hypofractionated stereotactic re-irradiation using CyberKnife®

The aim of the present study was to elucidate the effect of intratumoral abscess/necrosis (AN) on the outcome of patients with recurrent head and neck cancer (HNC) treated by stereotactic radiotherapy. The records of 67 patients treated with CyberKnife® in four institutes between August 2000 and July 2010 were reviewed. The frequency of AN appeared to be increased in younger postoperative patients with large ulcerative tumors. The AN⁺ group exhibited a better initial response rate compared with the AN⁻ group (64 vs. 33%, respectively; P=0.04). The 1-year local control rate was 51 and 75% in the AN⁺ and AN⁻ groups, respectively (P=0.01), while the respective 1-year overall survival rates were 53 and and 71% (P=0.0004). A total of 21 patients (31%) experienced grade ≥3 toxicities, and carotid blowout syndrome (CBOS) was found in 11 patients, resulting in 8 deaths. A significantly larger proportion of patients in the AN⁺ group developed CBOS (8/18; 44%) compared with the AN⁻ group (3/49; 6%) (P=0.001). Therefore, AN may be an important prognostic factor for patients with recurrent HNC, as well as a predictor of lethal toxicity due to CBOS.

Reirradiation for recurrent head and neck cancers using charged particle or photon radiotherapy

OBJECTIVE

To examine the outcomes of reirradiation for recurrent head and neck cancers using different modalities.

METHODS

This retrospective study included 26 patients who received charged particle radiotherapy (CP) and 150 who received photon radiotherapy (117 CyberKnife radiotherapy [CK] and 36 intensity-modulated radiotherapy [IMRT]). Inverse probability of treatment weighting (IPTW) involving propensity scores was used to reduce background selection bias.

RESULTS

Higher prescribed doses were used in CP than photon radiotherapy. The 1‑year overall survival (OS) rates were 67.9% for CP and 54.1% for photon radiotherapy (p = 0.15; 55% for CK and 51% for IMRT). In multivariate Cox regression, the significant prognostic factors for better survival were nasopharyngeal cancer, higher prescribed dose, and lower tumor volume. IPTW showed a statistically significant difference between CP and photon radiotherapy (p = 0.04). The local control rates for patients treated with CP and photon radiotherapy at 1 year were 66.9% (range 46.3-87.5%) and 67.1% (range 58.3-75.9%), respectively. A total of 48 patients (27%) experienced toxicity grade ≥3 (24% in the photon radiotherapy group and 46% in the CP group), including 17 patients with grade 5 toxicity. Multivariate analysis revealed that younger age and a larger planning target volume (PTV) were significant risk factors for grade 3 or worse toxicity.

CONCLUSION

CP provided superior survival outcome compared to photon radiotherapy. Tumor volume, primary site (nasopharyngeal), and prescribed dose were identified as survival factors. Younger patients with a larger PTV experienced toxicity grade ≥3.

Reirradiation using robotic image-guided stereotactic radiotherapy of recurrent head and neck cancer

The purpose of this study was to examine the prognosis for patients with head and neck cancer after reirradiation using Cyberknife stereotactic body irradiation with special focus on mucosal ulceration. We conducted a retrospective multi-institutional review of 107 patients with previously irradiated head and neck cancer. The median follow-up time for all patients was 15 months, and the 2-year overall survival rate was 35%. Significant prognostic factors for overall survival were primary site (nasopharynx versus other sites), presence of ulceration, and PTV volume. Detailed analysis of ulceration showed a lower response rate (28%) in the ulceration (+) group than the ulceration (-) group (63%; P = 0.0045). The 2-year overall survival rates were 8% in the ulceration (+) group and 42.7% (P = 0.0001) in the ulceration (-) group, respectively. We recorded 22 severe toxicities, including 11 patients with carotid blow-out syndrome (CBOS), which was fatal in 9 patients. CBOS occurred in 6 patients with ulceration (6/25; 24%), and 5 patients experienced CBOS without ulceration (5/82; 6%; P=0.027). In conclusion, ulceration is an important prognostic factor, not only for adverse events but also for survival after reirradiation using CyberKnife.

Predictive value of skin invasion in recurrent head and neck cancer patients treated by hypofractionated stereotactic re-irradiation using a cyberknife

BACKGROUND

This study aimed to elucidate the influence of skin invasion in patients with recurrent head and neck cancer treated with re-irradiation using stereotactic radiotherapy.

MATERIALS

We reviewed 104 patients treated using CyberKnife in four institutions.

RESULTS

Nine cases of skin invasion were recognized (8.6 %). Larger tumors tended to exhibit skin invasion. The skin invasion (+) group showed a lower response rate (0/9, 0 %) than the skin invasion (-) group (56/95, 59 %) (p = 0.002). The skin invasion (+) group showed lower local control (LC) and progression free survival (PFS) rates, both 0 % at 6 months, than the skin invasion (-) group, which had a LC of 69 % (p = 0.0001) and a PFS of 48 % at 1 year (p = 0.0157). Median survival time and one-year survival rates for the skin invasion (+) and (-) groups were 6.6 vs. 15.3 months and 14 % vs. 59 % (p = 0.0005), respectively. No patient with skin invasion survived more than 14.4 months. The percentage of patients who developed grade 3 or higher toxicity was 44 % in the skin invasion (+) group and 18 % in the skin invasion (-) group (p = 0.14).

CONCLUSIONS

Skin invasion is an important predictor of poor prognosis in recurrent head and neck cancer after re-irradiation with stereotactic radiation therapy.

Carotid blowout syndrome in pharyngeal cancer patients treated by hypofractionated stereotactic re-irradiation using CyberKnife: A multi-institutional matched-cohort analysis

BACKGROUND AND PURPOSE

Although reirradiation has attracted attention as a potential therapy for recurrent head and neck tumors with the advent of modern radiotherapy, severe rate toxicity such as carotid blowout syndrome (CBOS) limits its potential. The aim of this study was to identify the risk factors of CBOS after hypofractionated stereotactic radiotherapy (SBRT).

METHODS AND PATIENTS

We conducted a matched-pair design examination of pharyngeal cancer patients treated by CyberKnife reirradiation in four institutes. Twelve cases with CBOS were observed per 60 cases without CBOS cases. Prognostic factors for CBOS were analyzed and a risk classification model was constructed.

RESULTS

The median prescribed radiation dose was 30 Gy in 5 fractions with CyberKnife SBRT after 60 Gy/30 fractions of previous radiotherapy. The median duration between reirradiation and CBOS onset was 5 months (range, 0-69 months). CBOS cases showed a median survival time of 5.5 months compared to 22.8 months for non-CBOS cases (1-year survival rate, 36% vs.72%; p=0.003). Univariate analysis identified an angle of carotid invasion of >180°, the presence of ulceration, planning treatment volume, and irradiation to lymph node areas as statistically significant predisposing factors for CBOS. Only patients with carotid invasion of >180° developed CBOS (12/50, 24%), whereas no patient with tumor involvement less than a half semicircle around the carotid artery developed CBOS (0/22, 0%, p=0.03). Multivariate Cox hazard model analysis revealed that the presence of ulceration and irradiation to lymph nodes were statistically significant predisposing factors. Thus, we constructed a CBOS risk classification system: CBOS index=(summation of risk factors; carotid invasion >180°, presence of ulceration, lymph node area irradiation). This system sufficiently separated the risk groups.

CONCLUSION

The presence of ulceration and lymph node irradiation are risk factors of CBOS. The CBOS index, including carotid invasion of >180°, is useful in classifying the risk factors and determining the indications for reirradiation.

Antibody and lectin target podoplanin to inhibit oral squamous carcinoma cell migration and viability by distinct mechanisms

Podoplanin (PDPN) is a unique transmembrane receptor that promotes tumor cell motility. Indeed, PDPN may serve as a chemotherapeutic target for primary and metastatic cancer cells, particularly oral squamous cell carcinoma (OSCC) cells that cause most oral cancers. Here, we studied how a monoclonal antibody (NZ-1) and lectin (MASL) that target PDPN affect human OSCC cell motility and viability. Both reagents inhibited the migration of PDPN expressing OSCC cells at nanomolar concentrations before inhibiting cell viability at micromolar concentrations. In addition, both reagents induced mitochondrial membrane permeability transition to kill OSCC cells that express PDPN by caspase independent nonapoptotic necrosis. Furthermore, MASL displayed a surprisingly robust ability to target PDPN on OSCC cells within minutes of exposure, and significantly inhibited human OSCC dissemination in zebrafish embryos. Moreover, we report that human OSCC cells formed tumors that expressed PDPN in mice, and induced PDPN expression in infiltrating host murine cancer associated fibroblasts. Taken together, these data suggest that antibodies and lectins may be utilized to combat OSCC and other cancers that express PDPN.

Sarcomatoid (spindle cell) carcinoma of tongue: a report of two cases

Sarcomatoid Carcinoma (SC) is an unusual and aggressive variant of squamous cell carcinoma, which frequently recurs and metastasizes; for this reason, the right diagnosis is very important. It is considered to be a biphasic tumor made up of cells from squamous and spindle cells carcinoma with a sarcomatous aspect, but of epithelial origin. The diagnosis often represents a clinical-pathological challenge where the study with immunohistochemical technique (IHC) is key to the histopathological diagnosis. The reported cases related to oral mucosa are limited. In this work we present two SC cases where the use of IHC allowed us to achieve a conclusive diagnosis.

Histone deacetylase inhibitors in oral squamous cell carcinoma treatment

Introduction: The involvement of the histone deacetylases (HDACs) family in tumor development and progression is well demonstrated. HDAC inhibitors (HDACis) constitute a novel, heterogeneous family of highly selective anticancer agents that inhibit HDACs and present significant antitumor activity in several human malignancies, including oral squamous cell carcinoma (OSCC). Areas covered: This review summarizes the current research on the anticancer activity of HDACis against OSCC. The review also presents the molecular mechanisms of HDACis action and the existing studies evaluating their utilization in combined therapies of OSCC. Expert opinion: The currently available data support evidence that HDACis may provide new therapeutic options against OSCC, decreasing treatment side effects and allowing a more conservative therapeutic approach. Future research should be focused on in vivo and clinical evaluation of their utilization as combined therapies or monotherapies. Before HDACis can be brought into clinical practice as treatment options for OSCC, further evaluation is needed to determine their optimal dosage, the appropriate duration of treatment and whether they should be used in combination or as stand-alone therapeutics.

The influence of nodal yield in neck dissections on lymph node ratio in head and neck cancer

OBJECTIVES

Recent studies suggest that lymph node ratio (LNR) is a strong prognostic factor in head and neck cancer. This study aims to determine if the yield of harvested lymph nodes (LNs) influences the LNR.

METHODS

The study included 522 head and neck cancer patients, undergoing 638 primary and salvage (selective) neck dissections between 2002 and 2012. Before 2007 the neck dissection specimens were macroscopically and microscopically examined by pathologists and after 2007 the macroscopic examination was performed by pathology technicians. For comparison of mean LN yields, univariate and multivariate analyses were performed.

RESULTS

The mean number of LNs among 374 specimens examined by pathologists was 24 (range 0-89) vs. 32 (range 2-89) among 264 specimens examined by pathology technicians (P<.001). This caused the mean LNR in the non pre-treated patient group to drop from 11.4% to 8.7%. The counts of LNs per type of neck dissection were significantly different and increased with the number of levels involved. However, there was no linear relationship and the higher yields could be mostly ascribed to LNs in level V. The LNR varied from 8.1% to 18.4% among the different types of neck dissections.

CONCLUSIONS

A significant increase in the number of harvested LNs, but a decrease in LNR was observed after introducing pathology technicians for macroscopic examination. A clear association between the extent of the dissection and the number of harvested LNs was observed. LNR appears to be strongly dependent on the harvesting protocol and the extent of the dissection.

Clinical Assessment and Treatment of the Dysfunctional Larynx after Radiation

Objective

To review the pathophysiology of early and late radiation-related tissue changes, methods to differentiate these changes from disease recurrence, and treatment of these changes in the irradiated larynx.

Data Sources

Peer-reviewed publications.

Review Methods

PubMed database search.

Conclusions/Implications for Practice

Early and late radiation-related changes in the larynx manifest variably between individual patients. Severe radiation-related tissue changes in the larynx and recurrent malignancy share many clinical characteristics, and the presence of malignancy must be considered in these patients. Positron emission tomography may help select patients who need operative biopsy to rule out recurrence. In patients with a cancer-free but dysfunctional larynx, both surgical and nonsurgical treatment options, including hyperbaric oxygen, are available for attempted salvage. Further investigation is needed before hyperbaric oxygen can be considered standard-of-care treatment for these patients.

Potentiation of scutellarin on human tongue carcinoma xenograft by low-intensity ultrasound

Scutellarin 7-O-β-d-glucuronide (scutellarin) has shown great potential as a chemotherapeutic agent for cancer treatment, but only at high dosage. Here we investigate the possibility of using low intensity ultrasound to reduce the scutellarin dosage. Ultrasound intensities of 1.0 W/cm² and 0.05 W/cm² were used for in vivo and in vitro experiments, respectively, and a very low dosage of scutellarin (15 nM) was used. Tumor-bearing Balb/c mice and SAS human-tongue squamous carcinoma cell suspensions were used for the in vivo and in vitro experiments, respectively. Each kind of subjects was divided into control, ultrasound-alone, scutellarin-alone, and combined ultrasound-scutellarin treatment groups. Only the combined treatment showed strong anticancer effects. In the in vivo case, the combined treatment significantly delayed tumor growth, initiated cellular chromatin changes (including a decrease in the number of cytoplasmic organelles and fragmentation of condensed nuclear chromatin), inhibited tumor angiogenesis and lymphangiogenesis, stopped cancer-cell proliferation, decreased MMP-2 and MMP-9 expression levels and caused cancer-cell apoptosis. In the in vitro case, the combined treatment produced cancer cell-shape irregularity in a manner seriously fractured microvilli, inhibited cancer-cell migratory and invasion activities, and induced cancer-cell apoptosis. Because the combined treatment did not increase intracellular ROS production, scutellarin is not a sonosensitizer so that the anticancer effect is not through sonodynamic therapy. Low-intensity ultrasound is merely increasing the permeability of scutellarin into cancer cells. Based on our results, one may perform localized chemotherapy using much reduced dosage of the drug with the help of low intensity ultrasound, which will greatly minimize side effects.

Hypoxia in head and neck squamous cell carcinoma

Hypoxia is a common feature in most of the solid tumors including head and neck squamous cell carcinoma (HNSCC). Hypoxia reflects the imbalance between oxygen consumption by the rapidly proliferating cancer cells and the insufficient oxygen delivery due to poor vascularization and blood supply. The hypoxic microenvironment in the HNSCC contributes to the development of aggressive carcinoma phenotype with high metastatic rate, resistance to therapeutic agents, and higher tumor recurrence rates, leading to low therapeutic efficiency and poor outcome. To overcome the therapeutic resistance due to hypoxia and improving the prognosis of the HNSCC patients, many approaches have been examined in laboratory studies and clinical trials. In this short paper, we discuss the mechanisms involved in the resistance of radiotherapy and chemotherapy in hypoxic condition. We also exploit the molecular mechanisms employed by the HNSCC cells to adapt the hypoxic condition and their tumorigenic role in head and neck, as well as the strategies to overcome hypoxia-induced therapeutic resistance.

Current aspects on oral squamous cell carcinoma

Oral squamous cell carcinoma is the most common malignant epithelial neoplasm affecting the oral cavity. This article overviews the essential points of oral squamous cell carcinoma, highlighting its risk and genomic factors, the potential malignant disorders and the therapeutic approaches. It also emphasizes the importance of the early diagnosis.

Predicting recurrence after radiotherapy in head and neck cancer

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Radiotherapy is a mainstay of treatment, either alone for early stage tumors or combined with chemotherapy for late stage tumors. An overall 5-year survival rate of around 50% for HNSCC demonstrates that treatment is often unsuccessful. Prediction of outcome is, therefore, aimed at sparing patients from ineffective and toxic treatments on the one hand, and indicating more successful treatment modalities on the other. Both functional and genetic assays have been developed to predict intrinsic radiosensitivity, hypoxia, and repopulation rate. Few, however, have shown consistent correlations with outcome across multiple studies. Messenger RNA and microRNA profiling show promise for predicting hypoxia, whereas epidermal growth factor receptor expression combined with other measures of tumor differentiation grade shows promise for predicting repopulation rate. Intrinsic radiosensitivity assays have not proven useful to date, although development of repair protein foci assays indicates promise from preclinical studies. Assays for cancer stem cell content have shown promise in several clinical studies. In addition, 2 assays showing robustness as predictors for outcome in HNSCC are human papilloma virus status and epidermal growth factor receptor expression. Neither these nor stem cell assays, however, can as yet reliably indicate alternative and better treatments for poor prognosis patients. It would be of great value to have assays that predict the benefit for an individual from combining new molecularly targeted agents with radiotherapy to increase response, in particular those that exploit tumor mutations to provide tumor specificity. Predictive assays are being developed for detecting defects in repair pathways for single- and double-strand DNA breaks, which should allow selection of drugs targeting the appropriate backup pathway, thus exploiting the concept of synthetic lethality. This is one of the most promising areas for prediction, both currently and in the future.

Photodynamic therapy in the management of potentially malignant and malignant oral disorders

Photodynamic therapy (PDT) is a minimally-invasive surgical tool successfully targeting premalignant and malignant disorders in the head and neck, gastrointestinal tract, lungs and skin with greatly reduced morbidity and disfigurement. The technique is simple, can commonly be carried out in outpatient clinics, and is highly acceptable to patients. The role of photodynamic therapy in the management of oral potentially malignant disorders and early oral cancer is being discussed.

cTNM vs. pTNM: the effect of not applying ultrasonography in the identification of cervical nodal disease

Accurate clinical staging of oral squamous cell cancer can be quite difficult to achieve especially if nodal involvement is identified. Radiologically-assisted clinical staging is more accurate and informs the clinician of loco-regional and distant metastasis.In this study, we compared clinical TNM (cTNM) staging (not including ultrasonography) to pathological TNM (pTNM) staging in 245 patients presenting with carcinoma of the oral cavity and the oro-pharyngeal region. Tumour size differences and nodal involvement were highlighted. US reports of the neck were then added to the clinical staging and results compared.Tumour size was clinically underestimated in 4 T1, 2 T2 and 2 T3 oral diseases. Also 20 patients that were reported as nodal disease free had histological proven N1 or N2 nodal involvement; while 3 patients with cTNM showing N1 disease had histologically proven N2 disease.Overall the agreement between the 2 systems per 1 site was 86.6% (Kappa agreement = 0.80), per 2 sites 90.0% (Kappa agreement = 0.68) and per 3 sites 90.5% (Kappa agreement 0.62).An accurate clinical staging is of an utmost importance. It is the corner stone in which the surgical team build the surgical treatment plan and decide whether an adjuvant therapy is required to deal with any possible problem that might arise. The failure to achieve an accurate staging may lead to incomplete surgical planning and hence unforeseen problems that may adversely affect the patient's survival.

Photodynamic therapy outcome for T1/T2 N0 oral squamous cell carcinoma

INTRODUCTION

This new prospective clinical study assessed the oncological outcomes following surface illumination mTHPC-photodynamic therapy of T1/T2 N0 oral squamous cell carcinoma (OSCC) patients.

MATERIAL/METHODS

Thirty-eight patients participated in this study. Their mean age at the first diagnosis of OSCC was 58.0 years. Common clinical presentation was an ulcer mainly identified in the tongue, floor of mouth (FOM), or buccal mucosa. Current and ex-smokers represented 89.5% of the cohort; while current and ex-drinkers were 86.8%. Clinically nine patients had T1 disease while 29 had T2 disease.

RESULTS

Pathological analysis revealed that 12 patients had well differentiated SCC, 16 moderately differentiated and 10 had poorly-differentiated cancer. All patients were discussed in a multidisciplinary meeting and, subsequently, underwent mTHPC-PDT. PDT was repeated in 6- to 7-month period following the first round when residual tumor was identified in the treated site. At last clinic review post-PDT, 26/38 patients showed complete normal clinical appearance of their oral mucosa in the primary tumor site. Recent surgical biopsies from the study cohort showed that 17 had normal mucosa, five with hyperkeratinization, 10 with dysplastic changes and six showed recurrent SCC. The overall recurrence was 15.8% and the 5-year survival was 84.2%. Death from loco-regional and distant disease spread was identified in three patients. The recurrence group comprised six patients. Most common presentation was an ulcer involving the buccal mucosa or retromolar area, identified in current or ex-smokers and current drinkers. The surgical margins in this group were also evaluated following laser or surgical excision and reconstruction.

CONCLUSIONS

mTHPC-photodynamic therapy (up to three rounds) is a comparable modality to other traditional interventions in the management of low-risk tumors of the oral cavity. Although, sometimes, multiple rounds of the treatment is required, morbidity following PDT is far less when compared to the three conventional modalities: surgery, radiotherapy, and chemotherapy.

The treatment of oral cancer: an overview for dental professionals

Oral cancer is a serious life-threatening disease. Dental professionals may be the first individuals to identify/suspect these lesions before referring to oral and maxillofacial surgeons and oral medicine specialists. Because the general dentist will likely follow on with the patient's future oral health, it is important that he or she has a basic understanding of the various treatments involved in treating oral malignancies and their respective outcomes. The four main modalities discussed in this review include surgery alone, radiotherapy alone, surgery with radiotherapy, and chemotherapy with or without surgery and radiotherapy. Chemotherapy has become an area of great interest with the introduction of new 'targeted therapies' demonstrating promising results in conjunction with surgery. Despite these results, the toxicities associated with chemotherapy regimens are frequent and can be severe, and therefore may not be suitable for all patients. Treatment modalities have improved significantly over the decades with overall decreases in recurrence rates, improved disease-free and overall survival, and an improved quality of life. Prognosis, however, is still ultimately dependent on the clinical stage of the tumour at the initial diagnosis with respect to size, depth, extent, and metastasis as recurrence rates and survival rates plummet with disease progression.

TCRP1 promotes radioresistance of oral squamous cell carcinoma cells via Akt signal pathway

Tongue cancer resistance-associated protein 1 (TCRP1) is a novel gene located on human chromosome 11q13.4 which has been reported as a candidate related to chemotherapeutic resistance to cisplatin. Results suggest that TCRP also contribute to radioresistance in oral squamous cell carcinoma (OSCC) cells. We previously established exogenous overexpression of TCRP1 cell line Tca8113/TCRP1 and TCRP1 knockdown cell line Tca8113/PYM-siRNA and paired control cell lines, which provides a cell model system to investigate the roles and mechanisms of TCRP1-mediated radioresponse in OSCC. In this study, we first compared the radiosensitivity of up/down-regulating expression of TCRP1 cell lines and paired control cell lines by a clonogenic survival assay, Hoechst 33258 staining, cell growth assay, and comet assay. The results indicated that TCRP1 played a significant role in mediating OSCC radioresistance through decreased cells apoptosis and increased cellular proliferation and long-term survival. The further study found that TCRP1 function by up-regulating Akt activity and levels and then elevating the level of NF-κB. In summary, these results provided strong evidence for the linkage between TCRP1 and radiation sensitivity and may provide theoretical base of TCRP1 as a potential molecular mark of estimating the response for irradiation in OSCC.

Transient alteration of cellular redox buffering before irradiation triggers apoptosis in head and neck carcinoma stem and non-stem cells

Background

Head and neck squamous cell carcinoma (HNSCC) is an aggressive and recurrent malignancy owing to intrinsic radioresistance and lack of induction of apoptosis. The major focus of this work was to design a transient glutathione depleting strategy during the course of irradiation of HNSCC in order to overcome their radioresistance associated with redox adaptation.

Methodology/Principal Findings

Treatment of SQ20B cells with dimethylfumarate (DMF), a GSH-depleting agent, and L-Buthionine sulfoximine (BSO), an inhibitor of GSH biosynthesis 4 h before a 10 Gy irradiation led to the lowering of the endogenous GSH content to less than 10% of that in control cells and to the triggering of radiation-induced apoptotic cell death. The sequence of biochemical events after GSH depletion and irradiation included ASK-1 followed by JNK activation which resulted in the triggering of the intrinsic apoptotic pathway through Bax translocation to mitochondria.

Conclusions

This transient GSH depletion also triggered radiation-induced cell death in SQ20B stem cells, a key event to overcome locoregional recurrence of HNSCC. Finally, our in vivo data highlight the relevance for further clinical trials of endogenous redox modulation to enhance the cytotoxic effects of radiotherapy.

Prospective evaluation of outcome after transoral CO(2) laser resection of T1/T2 oral squamous cell carcinoma

OBJECTIVE

Oral cancer is the sixth most common cancer in the world. The incidence of oral squamous cell carcinoma (OSCC) continues to be high, if not increasing. This prospective study assessed the oncological outcomes following transoral CO(2) laser resection of T1/T2 N0 OSCC. Patients' 3-year disease-specific survival and disease-free survival were evaluated.

MATERIAL AND METHODS

The patients' data included a range of clinical, operative, and histopathological variables related to the status of the surgical margins. Data collection also included recurrence, cause of death, date of death, and last clinic review. Ninety patients (64 males and 26 females) participated in this study. Their mean age at the first diagnosis of OSCC was 63.5 years. Two thirds of the patients were Caucasians. Usually patients present with an ulcer of the tongue, floor of mouth, or buccal mucosa. Current and ex-smokers represented 82.2% of the cohort, whereas current and ex-drinkers were 78.9%. Comorbidities included history of oral lichen planus, oral submucous fibrosis, immunodeficiency, oral dysplasia, or OSCC. Clinically, 81 patients had T1N0 disease and 9 had T2N0 disease.

RESULTS

Pathologic analysis revealed that nearly half of the patients had moderately differentiated OSCC, 18 moderately to poorly differentiated, and 19 poorly differentiated carcinoma. Study of the tumor margins was carried out and showed a mean of 5.7-mm depth of invasion; tumor clearance was primarily achieved in 73 patients. Recurrence was identified in 11 (12%) patients. The mean age of first diagnosis of the recurrence group was 76.4 years. The most common clinical presentation in the recurrence group was an ulcer involving the tongue or buccal mucosa; most commonly were identified in current or ex-smokers or drinkers. Recurrence was associated with clinical N-stage disease. The surgical margins in this group were also evaluated following relaser excision or surgical excision ± neck dissection. Follow-up resulted in a 3-year survival of 86.7%. Twelve patients died: 9 from noncancer-related causes, 2 from locoregional disease spread, and 1 from distant metastasis to the lungs.

CONCLUSIONS

Squamous cell carcinoma of the oral cavity has a poor overall prognosis with a high tendency to recur at the primary site and extend to involve the locoregional lymph nodes. The overall results of this study suggest that CO(2) laser is a comparable modality to other traditional interventions (surgery) in the management of low-risk (T1/T2) tumors of the oral cavity.

The surgical palliation of advanced head and neck cancer using photodynamic therapy

End-stage head and neck cancer is a difficult disease to manage. The only curative treatment option remains surgery, but this is frequently not feasible. Often, however, significant palliation can be achieved with minimally invasive surgically directed treatments, such as photodynamic therapy. To avoid the morbidity of treating non-cancer areas, photodynamic therapy can now be very accurately directed by radiological imaging along pre-planned grids to document and optimise laser-guided photo-activation of the chemo-sensitiser. Rapid local tumour control often results, enabling the patient to benefit from both a higher quality and length of life.

When, how and why to treat the neck in patients with esthesioneuroblastoma: a review

Esthesioneuroblastoma is an uncommon tumor that presents in the sinonasal cavity and anterior skull base. Cervical metastases are not frequently found on initial presentation but eventually occur in 20-25% of these patients. This presents the treating physician with the difficult decision as to how and when to treat the neck in this disease. The aims of this study were to provide a comprehensive review of the incidence of N+ disease at presentation, make recommendations about the optimal treatment strategy of patients with N+ disease, explain the role of elective neck treatment in patients with N0 disease, and comment on treatment of patients with late cervical metastases that require salvage therapy, using the literature review of the incidence and treatment of neck disease in patients with esthesioneuroblastoma. This review revealed an approximately 5-8% incidence of cervical nodal metastasis at the time of presentation. Combined modality therapy with surgery and radiotherapy is recommended to treat the N+ neck at the time of diagnosis and later. Chemotherapy may have a role combined with radiation treatment, but there are little data to support this. There is limited evidence to substantiate the use of elective neck dissection or elective radiotherapy in the clinically and radiologically N0 neck. Patients who have late cervical metastases have a clear survival advantage (59 vs. 14%) when treated with combined surgery and radiotherapy relative to single modality methods alone. The results indicate that the management of the neck in esthesioneuroblastoma continues to be a significant challenge in the treatment algorithm of these complex patients.

Clinicopathological parameters, recurrence, locoregional and distant metastasis in 115 T1-T2 oral squamous cell carcinoma patients

The incidence of oral squamous cell carcinoma remains high. Oral and oro-pharyngeal carcinomas are the sixth most common cancer in the world. Several clinicopathological parameters have been implicated in prognosis, recurrence and survival, following oral squamous cell carcinoma. In this retrospective analysis, clinicopathological parameters of 115 T1/T2 OSCC were studied and compared to recurrence and death from tumour-related causes.

The study protocol was approved by the Joint UCL/UCLH committees of the ethics for human research. The patients' data was entered onto proformas, which were validated and checked by interval sampling. The fields included a range of clinical, operative and histopathological variables related to the status of the surgical margins. Data collection also included recurrence, cause of death, date of death and last clinic review. Causes of death were collated in 4 categories (1) death from locoregional spread, (2) death from distant metastasis, (3) death from bronchopulmonary pneumonia, and (4) death from any non-tumour event that lead to cardiorespiratory failure.

The patients' population comprised 65 males and 50 females. Their mean age at the 1^st diagnosis of OSCC was 61.7 years. Two-thirds of the patients were Caucasians. Primary sites were mainly identified in the tongue, floor of mouth (FOM), buccal mucosa and alveolus. Most of the identified OSCCs were low-risk (T1N0 and T2N0). All patients underwent primary resection ± neck dissection and reconstruction when necessary. Twenty-two patients needed adjuvant radiotherapy. Pathological analysis revealed that half of the patients had moderately differentiated OSCC. pTNM slightly differed from the cTNM and showed that 70.4% of the patients had low-risk OSCC. Tumour clearance was ultimately achieved in 107 patients. Follow-up resulted in a 3-year survival of 74.8% and a 5-year survival of 72.2%.

Recurrence was identified in 23 males and 20 females. The mean age of 1^st diagnosis of the recurrence group was 59.53 years. Most common oral sites included the lateral border of tongue and floor of mouth. Recurrence was associated with clinical N-stage disease. The surgical margins in this group was evaluated and found that 17 had non-cohesive invasion, 30 had dysplasia at margin, 21 had vascular invasion, 9 had nerve invasion and 3 had bony invasion. Severe dysplasia was present in 37 patients. Tumour clearance was achieved in only 8 patients. The mean depth of tumour invasion in the recurrence group was 7.6 mm.

An interesting finding was that 5/11 patients who died of distant metastasis had their primary disease in the tongue. Nodal disease comparison showed that 8/10 patients who died of locoregional metastasis and 8/11 patients who died from distant metastasis had clinical nodal involvement. Comparing this to pathological nodal disease (pTNM) showed that 10/10 patients and 10/11 patients who died from locoregional and distant metastasis, respectively, had nodal disease. All patients who died from locoregional and distant metastasis were shown to have recurrence after the primary tumour resection.

Squamous cell carcinoma of the oral cavity has a poor overall prognosis with a high tendency to recur at the primary site and extend to involve the cervical lymph nodes. Several clinicopathological parameters can be employed to assess outcome, recurrence and overall survival.

[Squamous cell carcinoma and potentially malignant disorders of the oral mucosa]

Squamous cell carcinoma is the most frequent malignant tumor of the oral mucosa. Various endogenous and exogenous factors promote its development. Therapy and prognosis depend mainly on tumor stage. Early detection is therefore of utmost importance. In most cases cancer develops from "leukoplakia". Both homogeneous leukoplakias as well as "erythroleukoplakias" should be biopsied. The"brush-biopsy", imaging techniques, molecular biologic or DNA tests are not reliable enough at present, often technically demanding and not applicable in daily practice. In extensive lesions "field cancerization" has to be considered. Further important precursor lesions are proliferative verrucous leukoplakia and erosive lichen planus. The management of oral precancerous lesions should be individually tailored: Low-grade dysplasia can be observed. If indicated, patients at risk should be biopsied in intervals. High-grade dysplasia ("carcinoma in situ") should be surgically removed.