18F-Fluorodeoxyglucose Positron Emission Tomography of Head and Neck Cancer: Location and HPV Specific Parameters for Potential Treatment Individualization.

Purpose: 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is utilized for staging and treatment planning of head and neck squamous cell carcinomas (HNSCC). Some older publications on the prognostic relevance showed inconclusive results, most probably due to small study sizes. This study evaluates the prognostic and potentially predictive value of FDG-PET in a large multi-center analysis. Methods: Original analysis of individual FDG-PET and patient data from 16 international centers (8 institutional datasets, 8 public repositories) with 1104 patients. All patients received curative intent radiotherapy/chemoradiation (CRT) and pre-treatment FDG-PET imaging. Primary tumors were semi-automatically delineated for calculation of SUVmax, SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG). Cox regression analyses were performed for event-free survival (EFS), overall survival (OS), loco-regional control (LRC) and freedom from distant metastases (FFDM). Results: FDG-PET parameters were associated with patient outcome in the whole cohort regarding clinical endpoints (EFS, OS, LRC, FFDM), in uni- and multivariate Cox regression analyses. Several previously published cut-off values were successfully validated. Subgroup analyses identified tumor- and human papillomavirus (HPV) specific parameters. In HPV positive oropharynx cancer (OPC) SUVmax was well suited to identify patients with excellent LRC for organ preservation. Patients with SUVmax of 14 or less were unlikely to develop loco-regional recurrence after definitive CRT. In contrast FDG PET parameters deliver only limited prognostic information in laryngeal cancer. Conclusion: FDG-PET parameters bear considerable prognostic value in HNSCC and potential predictive value in subgroups of patients, especially regarding treatment de-intensification and organ-preservation. The potential predictive value needs further validation in appropriate control groups. Further research on advanced imaging approaches including radiomics or artificial intelligence methods should implement the identified cut-off values as benchmark routine imaging parameters.

Influence of Semiquantitative [18F]FDG PET and Hematological Parameters on Survival in HNSCC Patients Using Neural Network Analysis.

The aim of this study is to assess the influence of semiquantitative PET-derived parameters as well as hematological parameters in overall survival in HNSCC patients using neural network analysis. Retrospective analysis was performed on 106 previously untreated HNSCC patients. Several PET-derived parameters (SUVmax, SUVmean, TotalSUV, MTV, TLG, TLRmax, TLRmean, TLRTLG, and HI) for primary tumor and lymph node with highest activity were assessed. Additionally, hematological parameters (LEU, LEU%, NEU, NEU%, MON, MON%, PLT, PLT%, NRL, and LMR) were also assessed. Patients were divided according to the diagnosis into the good and bad group. The data were evaluated using an artificial neural network (Neural Analyzer version 2.9.5) and conventional statistic. Statistically significant differences in PET-derived parameters in 5-year survival rate between group of patients with worse prognosis and good prognosis were shown in primary tumor SUVmax (10.0 vs. 7.7; p = 0.040), SUVmean (5.4 vs. 4.4; p = 0.047), MTV (23.2 vs. 14.5; p = 0.010), and TLG (155.0 vs. 87.5; p = 0.05), and mean liver TLG (27.8 vs. 30.4; p = 0.031), TLRmax (3.8 vs. 2.6; p = 0.019), TLRmean (2.8 vs. 1.9; p = 0.018), and in TLRTLG (5.6 vs. 2.3; p = 0.042). From hematological parameters, only LMR showed significant differences (2.5 vs. 3.2; p = 0.009). Final neural network showed that for ages above 60, primary tumors SUVmax, TotalSUV, MTV, TLG, TLRmax, and TLRmean over (9.7, 2255, 20.6, 145, 3.6, 2.6, respectively) are associated with worse survival. Our study shows that the neural network could serve as a supplement to PET-derived parameters and is helpful in finding prognostic parameters for overall survival in HNSCC.

Pectoralis major myocutaneous flaps vs. revascularised free tissue flaps following salvage surgery for recurrent head and neck cancer.

PURPOSE: To assess the efficacy of two reconstructive methods: pectoralis major myocutaneous flap and revascularised free flap in salvage surgery for recurrent head and neck cancer. PATIENTS AND METHODS: We retrospectively analysed 100 cases of patients who had recurrent head and neck cancer and were treated in the Department of Head and Neck Surgery between 2011 and 2021. The study participants were divided into two groups depending on the method of reconstruction: 62 patients who underwent revascularised free flap reconstruction and 38 patients with pectoralis major myocutaneous flap. RESULTS: In total, flap necrosis was observed in 20 cases, 18 of which were in the group who received revascularised free flaps (29.03%) and 2 in the pectoralis major myocutaneous flap group (5.26%). The OR of flap failure in the free flap group vs. pectoralis major flap group was 7.36 (95% CI 0.85-63.75; p=0.067) In the group who underwent revascularised free flap reconstruction the total surgery time was significantly longer than in the other group (p < 0.0001). CONCLUSION: We suggest the advantages of using pectoralis major myocutaneous flaps for recurrent head and cancers, which is of the utmost importance for malnourished patients in poor general health and whose primary treatment comprised of a combination therapy.

Dual-phase lag model of heat transfer between blood vessel and biological tissue.

A single blood vessel surrounded by the biological tissue with a tumor is considered. The influence of the heating technique (e.g. ultrasound, microwave, etc.) is described by setting a fixed temperature for the tumor which is higher than the blood and tissue temperature. The temperature distribution for the blood sub-domain is described by the energy equation written in the dual-phase lag convention, the temperature distribution in the biological tissue with a tumor is described also by the dual-phase lag equation. The boundary condition on the contact surface between blood vessel and biological tissue and the Neumann condition are also formulated using the extended Fourier law. So far in the literature, the temperature distribution in a blood vessel has been described by the classical energy equation. It is not clear whether the Fourier's law applies to highly heated tissues in which a significant thermal blood vessel is distinguished, therefore, taking into account the heterogeneous inner structure of the blood, the dual-phase lag equation is proposed for this sub-domain. The problem is solved by means of the implicit scheme of the finite difference method. The computations were performed for various values of delay times, which were taken from the available literature, and the influence of these values on the obtained temperature distributions was discussed.

A review of the 8th edition of the AJCC staging system for oropharyngeal cancer according to HPV status.

BACKGROUND: The incidence of oropharyngeal squamous cell carcinoma (OPSCC) has increased substantially in recent decades, particularly p16-positive human papillomavirus (HPV)-related OPSCC, which has risen by 50% in western countries. HPV-positivity is the most favourable non-anatomic predictor of oropharyngeal cancer outcomes, which underscores the importance of incorporating this variable into the cancer staging system. METHODS: In the present article, we review the differences between the 7th and 8th editions of the AJCC staging system, with particular focus on the role of HPV-positivity in patients with head and neck cancer. RESULTS: In the previous edition (7th edition) of the AJCC/UICC manual, HPV status and its correlation with nodal metastasis were not considered, thereby leading to incorrect lymph node (N) staging and, potentially, inadequate treatment and worse outcomes. The 8th edition of the AJCC manual addresses these issues, providing more accurate discrimination between groups and better risk stratification in patients with HPV-positive OPSCC. In the future, additional adjustments are likely to be needed, such as unification of the pathological and clinical staging models. CONCLUSIONS: The new staging system is substantially more accurate than the previous system and should be widely adopted in routine clinical practice.

Assessment of cartilage invasion in case of laryngeal cancer by means of longitudinal sectioning for histopathology - Clinical implications.

AIM: The aim of the study was to assess the accuracy of radiological diagnosis of laryngeal cartilage infiltration by histopathological examination of laryngeal specimen after total laryngectomy. BACKGROUND: Despite the development of new medical technologies and significant clinical advances allowing early diagnosis and treatment of laryngeal cancer, mortality is still on the rise. Neoplastic infiltration of the laryngeal cartilages is the most common source of error in the assessment of cancer staging. Furthermore, cartilage invasion is listed as a contraindication to partial surgical techniques as well as radiotherapy. MATERIALS AND METHODS: The study was carried out on 21 larynges following total laryngectomy. Before taking the decision to perform surgery, high-resolution CT scans were performed in all cases. An extended histopathological examination was conducted using a unique vertical cross-section of the whole larynx. RESULTS: Pathology reported 2 cases of arytenoid cartilage invasion, 5 cases of cricoid cartilage invasion, 12 cases of thyroid cartilage penetration, 1 case of internal cortex invasion and 9 cases of extra-laryngeal spread. CT imaging identified 8 of 13 cases (61.5%) of pathologically proven invasion of thyroid cartilage and only 2 cases (2/9, 22%) of extra-laryngeal spread. According to CT results, arytenoid cartilage invasion was correctly identified in 2 cases, cricoid cartilage invasion in 4 (4/5, 80%). The positive predictive values for thyroid, cricoid and arytenoid cartilage invasion and penetration were 80%, 66.7% and 50%, respectively. In case of pre-laryngeal spread the positive predictive value was 100%. CONCLUSION: Despite increasingly advanced methods involved in the diagnosis of laryngeal cancer, many discrepancies may be observed between the radiological and histopathological assessments. CT imaging has limitations especially in thyroid cartilage penetration and extra-laryngeal spread assessment in advanced laryngeal cancer cases. An extended histopathological examination, involving vertical cross-sections of the whole larynx is a very precise study that allows a precise determination of local cancer staging (T).

Robotic surgery (da Vinci Xi system) in head and neck cancer - own experience.

INTRODUCTION: Patients before 50 years of age with HPV-positive oropharyngeal cancer are characterized by significantly better survival than HPV-negative patients. The consequences of oncological treatment directly affect physiological function of the organs of the upper respiratory tract and, in consequence, the quality of life of these individuals. Therefore, the choice of therapy is of great importance. Minimally invasive surgery offers radical oncological treatment, while preserving the quality of life. The principal surgical methods are transoral access using TLM, electrosurgery and TORS. Radiochemotherapy as primary treatment is equally effective in the first and second stages of clinical advancement of cancer. However, occurrence of late complications such as swallowing, breathing, taste and smell disorders led to a recent re-emergence of minimally invasive surgery, particularly transoral robotic surgery, which has been widely used in head and neck surgery in the United States of America, Asia and Western European countries for more than 20 years. After many years, Poland joined the community of countries where the head and neck interventions are performed using the da Vinci Surgical System. OBJECTIVE: The purpose of the work is to present our own experience with the TORS at the Department of the Head and Neck Surgery and Laryngological Oncology of the Poznan University of Medical Sciences and to analyze the latest literature reports on the use of TORS in the treatment of oropharyngeal squamous cell carcinoma.

Numerical Simulation of Thermal Processes in a Domain of Thin Metal Film Subjected to an Ultrashort Laser Pulse.

A thin metal film subjected to an ultrashort laser pulse is considered. With a sufficiently high laser intensity the process of the film heating may cause metal melting and even ablation. In this work, the numerical model of the melting and resolidification processes is presented. The mathematical model is based on the dual phase lag equation in which two positive constants appear, this means the relaxation and thermalization times. The considered equation contains a second-order time derivative and higher order mixed derivative in both time and space and should be supplemented by the appropriate boundary and initial conditions. The model of the melting and resolidification is presented in two versions. The first can be called 'the introduction of the artificial mushy zone sub-domain', while the second 'the two forms of the basic energy equation'. At the stage of numerical computations, the implicit scheme of the finite difference method is used. The numerical algorithm is tested for the two proposed models which are applied to the computations concerning the thermal processes occurring in the cylindrical micro-domain (chromium, gold) subjected to an ultrashort laser pulse.

Blood Serum From Head and Neck Squamous Cell Carcinoma Patients Induces Altered MicroRNA and Target Gene Expression Profile in Treated Cells.

The head and neck squamous cell carcinoma (HNSCC) represents one of the most common cancers in humans. Close to 600,000 new diagnoses are made every year worldwide and over half of diagnosed patients will not survive. In view of this low survival rate, the development of novel cell-based assays for HNSCC will allow more mechanistic approaches for specific diagnostics for each individual patient. The cell-based assays will provide more informative data predicting cellular processes in treated patient, which in effect would improve patient follow up. More importantly, it will increase the specificity and effectiveness of therapeutic approaches. In this study, we investigated the role of serum from HNSCC patients on the regulation of microRNA (miRNA) expression in exposed cells in vitro. Next-generation sequencing of miRNA revealed that serum from HNSCC patients induced a different miRNA expression profile than the serum from healthy individuals. Out of 377 miRNA detected, we found that 16 miRNAs were differentially expressed when comparing cells exposed to serum from HNSCC or healthy individuals. The analysis of gene ontologies and pathway analysis revealed that these miRNA target genes were involved in biological cancer-related processes, including cell cycle and apoptosis. The real-time PCR analysis revealed that serum from HNSCC patients downregulate the expression level of five genes involved in carcinogenesis and two of these genes-P53 and SLC2A1-are direct targets of detected miRNAs. These novel findings provide new insight into how cancer-associated factors in circulation regulate the expression of genes and regulatory elements in distal cells in favor of tumorigenesis. This has the potential for new therapeutic approaches and more specific diagnostics with tumor-specific cell lines or single-cell in vitro assays for personalized treatment and early detection of primary tumors or metastasis.

Immunotherapy of head and neck squamous cell carcinoma (HNSCC). Immune checkpoint blockade.

Treating patients with squamous cell carcinoma of the head and neck is a significant problem. There is an increase in the incidence of malignant neoplasms in this region. Surgery, radiotherapy, and chemotherapy are often not sufficient methods of treatment. Thorough analysis of processes occurring in the tumor microenvironment has allowed to distinguish three stages that make up the reaction of the human body to hostile antigens, which are tumor antigens. Understanding these mechanisms has resulted in the introduction of a new term immunooncology. It is an area of cancer treatment that focuses on the use of the patient's immune system to combat the disease. Immunotherapy has had positive effects in cancer patients. The use of immune checkpoint inhibitors, such as anti-CTLA-4 and PD-1 monoclonal antibodies has enabled the modulation of T cell functions, consequently eliminating immunosuppression in the tumor microenvironment. Clinical trials were conducted using nivolumab and ipilimumab, which confirmed their clinical usefulness. The approval by FDA of nivolumab in the treatment of recurrent and metastatic squamous cell carcinoma of the head and neck has increased the overall survival time of patients as well as disease-free survival. Statistical data indicate an advantage of immunotherapy over other treatment methods at an advanced stage of cancer. This work aims to discuss basic issues related to immunotherapy, in particular, immunotherapy in patients with squamous cell carcinoma of the head and neck.

Multivariate analysis as an advantageous approach for prediction of the adverse outcome in head and neck microvascular reconstructive surgery.

BACKGROUND: The use of a free flap has become a mainstay of reconstruction following the ablative surgery in head and neck. The success rates are about 90%, however, several factors have been described to have an adverse effect on free flap survival. METHODS: We have performed a retrospective analysis of the treatment outcome of 93 microvascular flaps and evaluated the factors influencing the risk of flap loss including patients' age, body mass index, smoking, general medical history and previous oncological treatment. RESULTS: Out of 93 flaps the total necrosis have been observed in 15 flaps with gradual improvement in the consecutive years. In individual analysis the patients age, BMI, and comorbidities did not reveal any significant relation. The history of any previous oncological treatment represented a significant adverse factor of success rate (p=0.035), and was even more significant when patients experienced all treatment modalities prior to the reconstructive procedure (p=0.009). Multivariate logistic regression model indicated that only surgery (p=0.0008), chemotherapy (p=0.02), cardiovascular diseases (p=0.05) and patient's age (p=0.02) represented significant factors impairing the success rate. CONCLUSION: Incorporating multivariate analysis represents important statistical approach for better prediction of free flaps survival in head and neck reconstructive surgery. Incorporation of additional collective information could provide more precise approach in the risk of the flap loss assessment.

The role of otolaryngologist - head and neck surgeon's in the treatment of thyroid cancer.

INTRODUCTION: Thyroid gland is an integral part of the neck region. In the topographic anatomy of the head and neck the gland is located in the middle triangle of the neck. Therefore, it is an organ which is also subject for diagnostic and treatment by otorhinolaryngologists - head and neck surgeons. Material and methods The study group consists of 50 patients aged from 22 to 76 years (mean 48). All patients were treated for suspected thyroid tumor. The ratio of women to men was 35:15. In all patients the same panel of diagnostic tests was used including: endocrinologic consultation, ENT examination with stroboscopic examination with assessment of vocal cord mobility, neck ultrasound examination to assess the thyroid gland and lymph nodes. Results In 50 patients following surgical methods were used: total resection of the thyroid - 28 patients (56%), resection of one lobe of the thyroid - 17 (34%), open biopsy - 6 (12%) patients. In 5 cases tracheotomy was performed. In the case of malignancy (excluding unresctable lesions - 6 patients) selective lymph node dissection of the neck was performed (field III, IV, VI) - 11 patients (22%). Discussion Results of surgical treatment (relative to the percentage damage to the recurrent laryngeal nerve) achieved by head and neck surgeons are at levels comparable or higher compared to the results achieved by general surgeons - 1.3% for primary benign lesions (Enomoto et al.).

[Dental examination integral part of preventive testing head and neck cancers].

In recent years, in Poland and in Europe, we have seen a steady increase in the incidence of malignant tumors of the head and neck. On the basis of national cancer registries, the increase in new cases in the last ten years is over 15% and that worries epidemiologists and the medical community. Taken in Europe prevention programs aimed at reducing new cases. In Grater Poland from 2012 has initiated an innovative program for Early Detection of Cancer, Department of Head and Neck Surgery Medical University in Poznan and the Department of Health Marshal's Office in Poznan. The aim of the study was to evaluate dental and oral hygiene habits analysis of patients reporting to the Programme for Early Detection of Head and Neck Cancer. The study conducted involved 678 patients reporting to the Department of Head and Neck Surgery in Grater Poland Cancer Center under the prevention of cancers of the head and neck. All patients underwent ENT assessment and standard dental examination assessing condition of teeth and oral mucosa. All patients were asked to fill out prepared questionnaire, which included questions concerning socio-economic conditions of the patient, hygiene habits and risk factors for oral cancer. Most of the patients participating in the study, 441 people (65.9%) smoke or smoked cigarettes. Smoking habit among female dominated. Within smokers responders declared, at the same time,consumption of alcohol at least three times a week; 192 people (81.1%). Almost half (49.8%) of all respondents reported consuming alcohol occasionally. Regular practice of oral sex with frequent change of partner, belonging to the high risk of head and neck cancer, were found in 21.9% of patients. During the assessment of oral hygiene was observed 155 patients (23.4%) correctly cleansing the teeth and oral cavity, while more than half (62.4%) did not abide rules of daily oral hygiene. The use of additional tools to correct hygienization (dental floss, interdental brushes, rinses the mouth) was recorded in 51.7% of patients. As a result, 85% of the patients of the head and neck cancer prevention program was found bad condition of the oral cavity, and dental procedures in 30% of patients were applied. Patients diagnosed with invasive cancer was in 19 cases. Results of this study indicate that, the dentist should be an integral part of interdisciplinary team treating patients with head and neck cancer, and regular dental care plays a key role in the early diagnosis of patients with head and neck cancer.

Basal cell carcinoma in farmers: an occupation group at high risk.

INTRODUCTION: Skin cancer is the most commonly diagnosed cancer type worldwide, and 80 % of skin cancers are basal cell carcinoma (BCC). The main risk factor for developing BCC is exposure to ultraviolet radiation (UVR), particularly high-dose exposure at a young age. Outdoor workers, particularly farmers, are at high risk of developing BCC. However, studies of BCC in this population are scant. OBJECTIVE: To comprehensively evaluate all cases of BCC of the head and neck region treated during the years 2007-2013 at our hospital in Poland, and to compare the tumour characteristics in farmers to non-farmers. MATERIALS AND METHODS: Retrospective analysis of 312 patients treated for head and neck BCC during the study period (2007-2013). RESULTS: Most patients (198 cases; 63 %) were males, with 114 females (37 %). Median age was 73 years (range 32-96 years). The most common tumour location was the nose and cheek (114 pts; 37 %) followed by the auricle (82 pts; 26 %), lips (54 pts; 18 %), scalp (26 pts; 8 %), and eye (36 pts; 12 %). The most common disease stage on presentation was stage T2 (104 pts, 33 %), followed by stage T1 (79 pts; 25 %), stage T3 (89 pts; 28 %), and stage T4 (40 pts; 14 %). By occupation, farmers accounted for 33 % of all patients (102 of 312 pts). The most common tumour localisations in the farmer subgroup were the nose and cheek (50 pts; 49 %; p < 0.001; odds ratio [OR] 2.19; 95 % confidence interval [CI] 1.35-3.57), followed by the auricle (32 pts; 31 %), scalp (16 pts; 16 %), ocular region (3 pts; 3 %), and lips (1 pt; 1 %). Patients in the farmer group were significantly younger than non-farmers (62 vs. 73 years; p < 0.001; OR 0.90, 95 % CI 0.88-0.93). Farmers were significantly more likely to present disease recurrence (27 vs. 12 % of cases; p < 0.001; OR 5.94; 95 % CI 2.86-12.33). CONCLUSION: The results highlight the increased incidence and risk of recurrence of BCC in farmers. It is therefore necessary to consider enhancing educational programmes and other preventative measures in this occupational group and to evaluate the effectiveness of such programmes.

Carcinoma of unknown primary in the head and neck: The evaluation of the effectiveness of (18)F-FDG-PET/CT, own experience.

AIM: The aim of the present study was to estimate the clinical effectiveness of (18)F-FDG-PET/CT in the detection of the primary tumor in patients with histologically proven squamous cell carcinoma cervical lymph nodes metastasis from an unknown primary. BACKGROUND: (18)F-fluorodeoxyglucose positron emission tomography combined with CT ((18)F-FDG-PET/CT) is believed to be very helpful in localization of primary tumor in CUP Syndrome patients. MATERIAL AND METHOD: 41 patients referred to Poznan Medical University Department of Head and Neck Surgery from January 2010 to December 2013 with CUP Syndrome were included in the study. All patients presented fine-needle biopsy proven squamous cell carcinoma metastasis of the upper-, or mid neck lymph nodes. The final results were obtained from the histopathologic reports of tissue samples from anatomical regions suspected for primary tumor, additional imaging exams as well as clinical follow-up data. RESULTS: The (18)F-FDG-PET/CT successfully detected primary tumor in 7 out of 41 patients (17%). In two more cases the primary tumor was indicated in the lung. 24 of 41 patients (58.5%) analyzed in our study remained without evidence of a primary tumor. In 4 cases (9.75%) we did not reveal any pathology within the localizations indicated by PET/CT on panendoscopy. In 4 cases we obtained histological confirmation of neoplasm on panendoscopy despite the negative results of PET/CT examinations. CONCLUSION: We may suppose a relatively high usefulness of (18)F-FDG-PET/CT in the diagnosis process of CUP Syndrome patients. High NPV may indicate patients with no symptoms of primary tumor, which allows to avoid extensive resection or extra imaging.

National Programme for Prevention and Early Detection of Head and Neck Cancer.

550,000 new cases of cancer of the oral cavity and pharynx and 160,000 of larynx are diagnosed each year worldwide. It is estimated that each year because of head and neck cancer 400,000 of patients will die. Head and neck neoplasms are the tumors which, because of their location, secretly develop and produce uncharacteristic symptoms identical to those that accompany the banal infections of the upper respiratory tract. Results of treatment of patients with head and neck cancer in Poland are highly unsatisfactory. This is due to significant advancement of tumor at the moment of diagnosis. Therefore, raising awareness and improving knowledge of health care workers on head and neck cancers by creating access to prevention research is a priority that will ensure improvement in treatment outcomes in this group of tumors in Poland and abroad.

Uncontrolled human papilloma virus infection in a 28-year-old man leading to death - case report and review of literature.

Recurrent respiratory papillomatosis is an increasingly common disease which leads to organic and functional limitations. Clinical symptoms depend on the location and extent of the papillomatosis. They include hoarseness, cough, and, in some cases, significant narrowing of the respiratory and digestive tracts. The present report describes a fatal case of a young man (28 years old) who developed a very dynamic papilloma infection of the larynx, which spread to the trachea, the oesophagus, the soft tissues of the neck, and the mediastinum. Multimodal treatment did not stop the progression of the disease. The papillomatous lesion was removed with a CO2 laser used in a Kleinsasser microlaryngoscopy and under a microscope using a electrocoagulation loop with argon plasma during the gastroscopy. Antiviral treatment with cidofovir was introduced, as well as in further follow-up radiotherapy. Congenital or acquired immunodeficiency was also excluded. Despite multimodal treatment, successful eradication of the infection was not possible. In our case, aggressive progression of the disease was observed. We were unable to confirm malignant transformation. Papillomatosis was the only disease, and its aggressive development led to the patient's death. In the case of aggressive, uncontrolled progression - when the infiltration spreads beyond the larynx and the hypopharynx - there are no alternative treatment methods that would lead to an effective cure.

The BEM-FDM model of thermal processes proceeding in the domain of the human finger.

PURPOSE: The problem of the numerical modeling of thermal processes proceeding in the non-homogeneous domain of the human finger is discussed. The domain considered constitutes the assembling of soft and bone tissues and the system of supplying blood vessels (arteries and veins). The mathematical description of the process analyzed corresponds to the so-called vascular models. METHODS: At the stage of numerical modeling the algorithm being the composition of the boundary element method (BEM) and the finite difference method (FDM) is applied. RESULTS: The algorithm presented allows one to determine the steady state temperature field in the finger domain in natural convection conditions. To verify the effectiveness and exactness of the method of the problem solution, the thermal imaging measurements of the finger surface temperature have been done. CONCLUSIONS: The compatibility of numerical and experimental results (the natural convection conditions) has proved to be quite satisfactory. It is possible to use the algorithm proposed for the modeling of thermal processes proceeding in the conditions of low or high ambient temperatures and the big values of heat transfer coefficients. The impact of protective clothing on the temperature field in the domain of the finger can also be analyzed.

Analysis of selected recurrence risk factors after treatment of head and neck basal cell carcinoma.

INTRODUCTION: Basal cell carcinoma (BCC) is the most common type of non-melanoma malignant skin tumors. Eighty-five percent of all cases are located on the skin of the head and neck. The risk of recurrence after surgery is estimated at 5-15%. AIM: To evaluate the selected risk factors for recurrence after surgical treatment of head and neck BCC at the Department of Head and Neck Surgery in the Greater Poland Cancer Centre of the Poznan University of Medical Sciences. MATERIAL AND METHODS: A retrospective analysis was made of patients treated at the Department of Head and Neck Surgery in the Greater Poland Cancer Centre of the Poznan University of Medical Sciences in 2007-2012 for BCC of the head and neck region. The study covered 312 patients: 198 males (63%) and 114 females (37%), aged 32-96 years. RESULTS: In the study group of 312 tumors, recurrence after initial treatment in this Centre was diagnosed in 18 patients (9%), whereas in patients who were previously operated elsewhere, recurrence was found in 22 cases (17%). The nodular type was the most common BCC type in the study group and concerned 175 patients (56%). The most numerous group (114; 37%) in this study group comprised patients with external nose and cheek tumors. CONCLUSIONS: The importance of preoperative biopsy to assess the histological type as a routine treatment of patients with BCC is essential. Ultrasound evaluation to assess the exact size and depth of tumor invasion should also be implemented.

Oral cavity and oropharyngeal squamous cell carcinoma in young adults: a review of the literature.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is a disease of middle-aged to elderly adults. However, an increased incidence of HNSCC in young people under 45 years of age has been reported recently. In the present review, we focused on the epidemiology and aetiology of HNSCC in adults under 45 years of age. METHODS: We reviewed literature related to HNSCC in adult patients less than 45 years of age and discussed current treatment options and prognosis. RESULTS: HNSCC in young adults is associated with a higher incidence rate in nonsmokers, lower female-to-male ratio, a higher percentage of oral cavity and oropharynx tumours, and fewer second primary tumours. However, aside from traditional risk factors of tobacco and alcohol exposure, the causes of these cancers in young adults remain unclear. Agents that might contribute to risk include infection with high-risk human papillomavirus subtypes as well as genetic factors or immunodeficiency status. The expected increase in incidence and mortality of the young with HNSCC may become a major public health concern if current trends persist, particularly lifestyle habits that may contribute to this disease. CONCLUSIONS: Given the younger age and potential long-term adverse sequelae of traditional HNSCC treatments, young adults should be treated on a case-by-case basis and post-therapy quality of life must be considered in any treatment-decision making process.