Head and neck cancer, treatment, evolution and post therapeutic survival – Part 2: A decade's results 1993–2002

Biomechanical behavior of mandible with posterior marginal resection using finite element analysis

This study aims to characterize biomechanical behavior of various designs of posterior mandibular marginal resection under functional loadings using finite element method. The ultimate goal of this work is to provide clinically relevant information to prevent postoperative fracture and to stipulate prophylactic internal fixation for planning of marginal mandibulectomy. A 3D mandibular master model was reconstructed from cone beam computed tomography images. Different marginal resection models were created based on three design parameters, namely, defect curvilinear radius, anterior-posterior defect width and residual height of the mandibular body. Functional loadings from incisors (60 N) and contralateral first molar area (200 N) were applied to designed models and stress patterns were compared of five groups with curvilinear radius from 0 (conventional rectangular shape), 2.5, 3.5, 5, and 6 mm. Models with 25, 35 and 45 mm defect width mimic defects varied from canine to 3rd molar were tested. Residual height range from 10 to 4 mm was assessed. The results show high stresses predominated in the occlusal area and the posterior inferior border near the resection corner. The average maximum stress decreased by 29.8% (r = 2.5 mm), 51.9% (r = 3.5 mm), 54.4% (r = 5 mm), and 59.3% (r = 6 mm) compared to the baseline of r = 0 mm. The results from the combined defect width/residual height models demonstrate the increase of defect width and the decrease in residual height resulted in the increase of maximum stress. Our data also confirm that the factor of residual height supersedes defect width in terms of prevention of postoperative fracture when considering resection design.

Evaluation of salivary and serum lipid peroxidation, and glutathione in oral leukoplakia and oral squamous cell carcinoma

Lipid peroxidation induced by reactive oxygen species (ROS) is involved in the pathogenesis of malignancy. Overall, lipid peroxidation levels are indicated by malondialdehyde (MDA), which is the most frequently used biomarker to detect oxidative changes. Antioxidant defense systems such as glutathione (GSH) limit cell injury induced by ROS. Therefore, MDA and GSH can be used to monitor oxidative stress (OS). Hence, this study aimed to evaluate and compare both salivary and serum levels of MDA and GSH in oral leukoplakia and oral squamous cell carcinoma (OSCC) patients, and healthy controls. The study included 100 subjects comprising 30 apparently healthy controls, 30 patients with oral leukoplakia and 40 clinically and histologically diagnosed patients with OSCC. Saliva and blood samples were obtained and evaluated for MDA and GSH. The study revealed enhanced MDA levels in saliva and serum in oral leukoplakia and OSCC patients as compared to controls. On the other hand, significant decreases were seen in serum and salivary GSH levels in oral leukoplakia and OSCC patients as compared to controls. Augmentation of OS in blood and saliva is reflected by increase in MDA and decrease in GSH levels, indicating that tumor processes cause an imbalance of oxidant-antioxidant status in cell structures.

The relevance of EGFR overexpression for the prediction of the malignant transformation of oral leukoplakia

The present study evaluated the relevance of EGFR overexpression in prediction of malignant transformation of oral leukoplakia (OLP). The retrospective study comprised paraffin-embedded tissue samples of OLP that transformed into oral squamous cell carcinoma (OSCC) (n=53) and tissue samples of OLP that did not transform into OSCC (n=45) during a follow-up period of 5 years. EGFR overexpression was assessed immunohistochemically. A significantly different expression rate of EGFR was determined between transformed and non-transformed OLP (p=0.017). A statistically significant increase of EGFR expression for low dysplasia lesions in group I compared to group II was proven (D0, p=0.013; D1, p=0.049). By calculation of ROC curve and determination of highest Youden index the optimal threshold value [cut-off point (COP) = 44.96] for distinguishing the transformed from non-transformed lesions was estimated (critical expression rate of EGFR). Using the determined COP the correlation between high-risk lesions and the detection of increased expression rates were significant (p=0.001). In the future, the assessment of EGFR overexpression in OLP may allow identifying OLP lesions with an increased risk of malignant transformation that may have been regarded harmless when only the grade of dysplasia had been taken into account.

Evaluation of MAGE-A expression and grade of dysplasia for predicting malignant progression of oral leukoplakia

The risk of the malignant transformation of oral leukoplakia (OLP) is difficult to predict by histopathology. Melanoma-associated antigen-A (MAGE-A) expression is restricted to malignant cells and may be useful for the more accurate estimation of the potential malignant transformation of pre-malignant lesions. The aim of the present study was to investigate whether the expression of MAGE-A can be used to predict the malignant transformation of OLP. Paraffin-embedded tissue samples of OLP from 74 patients followed-up for at least 5 years were included. A total of 24 progressing and 50 non-progressing OLP, 18 corresponding tumor and 30 healthy mucosa specimens were analysed for MAGE-A 1, 3, 4, 6 10 and 12 expression by nested real‑time RT-PCR and graded for dysplasia. In total, 46% of the progressing lesions expressed at least 1 out of the examined MAGE-A antigens, whereas no expression was detected in any of the non-progressing OLP and normal specimens. The correlation between malignant transformation and MAGE-A expression was statistically significant (p=0.00001). Furthermore, 42% of the progressing OLPs without dysplasia (D0) expressed at least 1 antigen. The correlation between the grade of dysplasia and MAGE-A staining in the malignant transformation group was not significant (p=0.08). The detection of at least 1 MAGE-A antigen may allow the identification of high-risk lesions that may progress into carcinoma with time. Therefore, the investigation of MAGE-A expression should be assessed in order to obtain a more accurate evaluation of the potential cancer risk of OLP.

Detection of MAGE-A expression predicts malignant transformation of oral leukoplakia

The study aimed at checking if MAGE-A expression in oral leukoplakia (OLP) lesions is related to malignant transformation. The 48 samples of OLP that transformed to oral squamous cell carcinoma (OSCC) (group 1) and 50 samples of OLP that did not transform to OSCC (group 2) were included in the study. The expression of MAGE-A was restricted to group 1. The correlation between malignant transformation and MAGE-A occurrence in OLP was statistically significant (p < .0001). Detection of MAGE-A may allow identifying OLP with a high risk of malignant transformation giving a view to a new approach to prevention of oral cancer.

Preoperative concurrent chemoradiotherapy for stages II-IV oral squamous cell carcinoma: a retrospective analysis and the future possibility of this treatment strategy

This study evaluated survival in 154 patients with stages II-IV oral squamous cell carcinoma (OSCC) treated with preoperative concurrent chemoradiotherapy and assessed the future use of this treatment strategy. 14 patients exhibited advanced stage II, 73 exhibited stage III and 67 exhibited stage IV. All patients received 40Gy irradiation and concurrent cisplatin-based chemotherapy in two courses. Radical surgery was undertaken after 2-6 weeks. The clinical tumour response, histopathologic regression grade, residual tumour grade (RGrade) in the primary tumour and the level of residual pN+ were associated with prognosis. 90% of patients with complete response and 73% of patients with good partial response in the primary tumour were RGrade 0 (no residual tumour cells) or RGrade 1 (viable tumour cells remained within central superficial portion). In patients with complete response in the neck, residual pN+ was only seen in levels IB (8%) and IIA (8%); the higher the level of residual pN+, the lower the survival rate (p<0.0001). This treatment strategy was excellent for stages II-IV OSCC. It may be possible to perform minimally invasive surgery in which the extent of resection in primary tumour and neck is reduced in patients who achieve good response following preoperative chemoradiotherapy.

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.

A modified midfacial degloving approach for the treatment of unilateral paranasal sinus tumours

PURPOSE

The midfacial degloving approach (MFDA) is the primary option for the removal of benign and malignant sinonasal tumours. However, the classic MFDA does not compensate for the fact that most benign and malignant paranasal sinus (PNS) tumours are unilateral and the incisions may lead to some unnecessary complications?. Surgical exposure is limited to the upper and deep part of the PNS. Modifications of the classical MFDA that minimize complications and improve surgical field exposure are warranted.

PATIENTS

The medical records of 27 consecutive patients who had undergone surgery using a modified MFDA for treatment of unilateral benign or malignant tumours from 2000 to 2006, were reviewed.

RESULTS

We developed and performed a modified MFDA utilizing a hemigingivobuccal incision, a transfixion incision, mucosal detachment of the pyriform aperture and separation of the upper lateral cartilage from the nasal bone in 27 patients with unilateral benign (85%) or malignant (15%) PNS neoplasms. Adequate surgical exposure was achieved in all cases. No technical problems and no intraoperative complications related to the surgical procedure were encountered.

CONCLUSION

Our modified MFDA provides sufficient surgical exposure for the removal of unilateral malignant or benign PNS tumours with few surgical or cosmetic complications.

Aesthetic and functional radical surgery in young patients with stage one or two tongue cancer: a preliminary report

INTRODUCTION

The effect of an initial radical cure and the post-operative quality of life in young patients with stage one or two tongue cancer seems to be more important than in old patients. The aim of this study was to achieve both optimal surgical effectiveness and improved post-operative quality of life for young patients with stage one or two tongue cancer.

MATERIALS AND METHODS

7 patients under 40 years of age with T(1)-T(2)N(0)M(0) squamous cell carcinoma of tongue underwent aesthetic and functional radical surgery in which reconstruction of the defect in the oral cavity and conservation of the main functional organs in neck with good scar aesthetics in the face and neck were performed. The outcomes were assessed clinically.

RESULTS

No tumour recurrence was found in the tongue, floor of mouth or neck at the end of follow-up (at least 37 months). The appearance of the tongue and oral function was retained; function in face, neck and shoulder was maintained; a satisfactory cosmetic appearance of the face and neck was achieved.

CONCLUSIONS

Aesthetic and functional radical surgery could ensure radical cure and unchanged, or improved post-operative, quality of life in young patients with stage one or two tongue cancer.

MAGE-A antigens in lesions of the oral mucosa

Oral squamous cell carcinoma develops continuously out of predamaged oral mucosa. For the physician and pathologist, difficulties arise in distinguishing precancerous from cancerous lesions. MAGE-A antigens are tumor antigens that are found solely in malignant transformed cells. These antigens might be useful in distinguishing precancerous from cancerous lesions. The aim of this study was to verify this assumption by comparing MAGE-A expression in benign, precancerous, and cancerous lesions of the oral mucosa. Retrospectively, biopsies of different oral lesions were randomly selected. The lesions that were included are 64 benign oral lesions (25 traumatic lesions (oral ulcers), 13 dental follicles, and 26 epulis), 26 oral lichen planus, 123 epithelial precursor lesions (32 epithelial hyperplasia found in leukoplakias, 24 epithelial dysplasia found in leukoplakias, 26 erythroplasia with oral epithelial dysplasia, and 41 carcinomas in situ in erythroleukoplakias). The lesions were immunohistochemically stained with the poly-MAGE-A antibody 57B, and the results were compared. Biopsies of oral lichen planus, oral ulcers, dental follicles, epulis, and leukoplakia without dysplasia showed no positive staining for MAGE-A antigens. Leukoplakia with dysplasia, dysplasia, and carcinomata in situ displayed positive staining in 33%, 65%, and 56% of the cases, respectively. MAGE-A antigens were not detectable via immunohistochemistry in benign lesions of the oral mucosa. The staining rate of dysplastic precancerous lesions or malignant lesions ranged from 33% to 65%. The MAGE-A antigens might facilitate better differentiation between precancerous and cancerous lesions of the oral mucosa.

Mutagenic evaluation of combined paclitaxel and cisplatin treatment in somatic cells of Drosophila melanogaster

Recent studies have added paclitaxel (PAC) to traditional cisplatin (CIS) regimen to treat squamous cell carcinoma of the head and neck. The target of these antineoplastic agents is nuclear DNA for CIS and microtubules for PAC, although it is not restricted to malignant cells. In this study, the genotoxicity of the combined treatment of PAC and CIS was investigated using the standard version of the wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster. Quantitative and qualitative genotoxic effects of these compounds were estimated by comparing wing spot frequencies in marker-heterozygous to balancer-heterozygous flies. Two different concentrations of PAC (0.0025 and 0.005mM) and CIS (0.025 and 0.05mM) as well as combinations of them were employed. The results demonstrated that the spindle poison PAC alone was not genotoxic in this test system, while CIS was able to induce a high incidence of DNA damage in both genotypes, mainly related to somatic recombination. The data obtained for the combined treatments showed that its genotoxicity varied with the concentrations used. In small concentrations the number of total spots induced by combination was reduced in relation to CIS 0.025mM just for marker-heterozygous flies, showing that somatic recombination was the prevalent event involved. At higher concentrations the combined treatment showed significant reductions in the frequencies of large single spots, for both genotypes, and twin spots for marker-heterozygous flies, but did not significantly reduce the total spots frequency in either genotype. The data suggest that aneugenic activity of PAC could be responsible for the reduction in the genotoxicity of CIS.

Salvage treatment for recurrent oral squamous cell carcinoma

The treatment failures of oral squamous cell carcinoma (OSCC) are mostly local and regional recurrences. The aim was to estimate the prognosis of patients with recurrent OSCC through the prognostic staging system. We reviewed 81 patients with recurrent OSCC from April 1, 1999, to April 1, 2005. The independent prognostic factors for the patients with recurrent OSCC were identified by the univariate and multivariate Cox regression analyses. Then, to develop a prognostic staging system, and according to this staging system, the patients with recurrent OSCC were divided to 4 stages. By the Kaplan-Meier and log-rank statistical analyses, we found that the survival rate of patients with recurrent OSCC was significantly different at the different developmental stages. The primary TNM cancer stage before initial treatment, the extent of recurrence, and the recurrent tumor size are the independent prognostic factors for the patients with recurrent OSCC. Through this clinical study, the earlier-stage cases (stages I and II) for the patients with recurrent OSCC had a significantly better survival outcome compared with the advanced-stage cases (stages III and IV), and at the early recurrent stage, the salvage surgery represented a reliable and feasible treatment method.

The role of surgery and radiotherapy in treatment of soft tissue sarcomas of the head and neck region: review of 30 cases

BACKGROUND

Thirty adult patients with head and neck soft tissue sarcoma (HNSTS) treated between 1987 and 2000 were retrospectively analysed.

PATIENTS AND METHODS

The most frequent histopathological subtypes were chondrosarcomas (27%) and malignant fibrous histiocytoma (20%). The surgical resection was performed in 25 of the 30 patients (83%). Twenty-three patients in the surgical resection arm received postoperative radiotherapy.

RESULTS

Five-year local control rates for patients with negative surgical margins (n=9), microscopically positive disease (n=10), gross residual disease (n=6) and inoperable cases (n=5) were 64, 70, 20 and 0%, respectively. However, there was no significant difference in local control between patients with negative or microscopically positive disease who received postoperative radiotherapy (71 vs. 70%). The patients who received doses>or=60 Gy had significantly higher local control rates than the ones who received doses lower than 60 Gy (p=0.048). The local control rates were lower in patients with grade 2-3 tumours when compared with grade 1 tumours (44 vs. 83%). The median overall survival of whole group was 31 months. Median survivals of patients receiving both surgery and radiotherapy with negative and microscopically positive margins were significantly better than patients who were not treated with surgery (34.8 and 36 vs. 13.3 months).

CONCLUSION

Our results confirm that the optimal treatment of HNSTSs is complete surgical excision, and that postoperative adjuvant radiotherapy clearly improves local control.

Preoperative chemoradiotherapy in the management of oral cancer: a review

INTRODUCTION

Multi-modality treatment concepts involving preoperative radiotherapy (RT) or chemoradiotherapy (CRT) and subsequent radical resection are used much less frequently than postoperative treatment for oral and oropharyngeal squamous cell carcinomas. In some centres, however, the preoperative approach has been established for several years.

MATERIAL

The present review is a compilation of the existing evidence on this subject.

METHODS

In a literature-based meta-analysis, the survival data of 1927 patients from 32 eligible publications were analysed.

RESULTS

The calculated survival rates of documented patients show remarkably good results with preoperative CRT and radical surgery. However, the findings of this analysis are based on data with a large proportion of studies using consecutive patient series.

CONCLUSION

Hard evidence providing sufficient data from prospective randomised studies is as yet missing for preoperative CRT. Prospective randomised studies are mandatory in this area.