THE IMPACT OF COVID-19 ON HEAD AND NECK CANCER TREATMENT DELAY.

The aim of this study was to demonstrate the impact of COVID-19 pandemic on the number and characteristics of head and neck cancer patients in two consecutive periods, pre-pandemic and pandemic. For this purpose, we performed a retrospective analysis of patients with primary carcinomas of head and neck mucosal sites, salivary gland tumors, as well as neck metastases. Two pre-COVID-19 years (2018-2019) and two pandemic years (2020-2021) were compared. Demographic data, overall number of patients, TNM classification of the two most affected sites (oral cavity and larynx), time from symptom onset to first outpatient admission to our department, and time from first admission to treatment initiation were noted. Study results revealed a higher number of patients during the pandemic period and difference in the distribution of tumor sites (χ2=33.68, df=9, p<0.001). Oral cavity cancer prevailed over laryngeal cancer during the pandemic period. A statistically significant difference was observed in delay of initial presentation to head and neck surgeon for oral cavity cancer during the pandemic period (p=0.019). Furthermore, significant delay was found for both sites concerning time from initial presentation to the beginning of treatment (larynx: p=0.001 and oral cavity: p=0.006). Despite these facts, there were no differences in TNM stages comparing two observed periods. Study results indicated that there was a statistically significant delay of surgical treatment for both cancer sites observed (oral cavity and larynx) during the COVID-19 pandemic. A survival study is necessary in the future to definitely reveal the true consequences of COVID-19 pandemic on treatment outcomes.

TREATMENT OF EARLY GLOTTIC CARCINOMA WITH TRANSORAL ENDOSCOPIC LASER SURGERY.

Laryngeal carcinoma is one of the most common tumors of the head and neck, just after skin cancer. Alongside open surgery, transoral endoscopic laser surgery (TOLS) has become widespread as a treatment method. Our aim was to assess the efficacy of transoral laser cordectomy in a group of patients with early glottic carcinoma. We retrospectively analyzed data on 131 patients who underwent TOLS in the 2017-2021 period. We divided patients into groups according to tumor stage and type of cordectomy performed, and compared outcomes between the groups. Our results revealed a higher number of patients in the group with Tis and T1a than in those with T1b and T2 who underwent type III cordectomy, and also a higher number of those for whom outpatient follow-ups were sufficient after surgery in the same group. We did not observe significant difference in outcomes according to cordectomy type except for type V (a-d), where a higher number of patients had to undergo radiotherapy. This study underlines the importance of careful patient selection for TOLS, as well as the need for close cooperation with pathology and radiology specialists to ensure optimal approach and extent of surgery for each individual patient. It also displayed TOLS as a sound therapeutic option for early stages of glottic carcinoma but also indicated the need for similar studies in a larger number of patients to elucidate the effectiveness in certain glottis areas.

Overview of Thyroid Surgery Complications.

INTRODUCTION: The most obvious indication for thyroid surgery is malignancy, but other indications are also not rare. As with any other surgical procedure, those surgeries also carry risks which can be classified as minor or major. DISCUSSION: In this overview, we present minor (seroma, scarring) and major complications of thyroid surgery (recurrent nerve injury, hypoparathyroidism, and bleeding). We discuss the possibilities of prevention and treatment of each of those complications. CONCLUSION: In recent years, thyroid surgery is becoming safer due to the development of new surgical, hemostatic, and other techniques such as intraoperative monitoring of the recurrent laryngeal nerve and parathyroid gland detection.

HPV-driven oropharyngeal squamous cell cancer in Croatia - Demography and survival.

OBJECTIVES: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide. Main HNSCC risk factors are tobacco, alcohol, and high-risk human papillomavirus (HPV). HPV+ oropharyngeal squamous cell cancer (OPSCC) usually have different etiology, increasing incidence and often show an improved survival when compared to HPV-negative cases. The objective of the current study was to retrospectively examine the influence of HPV on the survival of OPSCC patients in a non-Western population setting. MATERIALS AND METHODS: We determined the presence of HPV DNA and/or RNA in 99 formalin-fixed paraffin embedded (FFPE) tissue samples of OPSCC patients treated between 2002 and 2015. Patients were compared based on laboratory, demographic, clinical, life style characteristics and survival. RESULTS: HPV RNA was found in 29.3% cases. However, groups based on HPV data (either RNA, DNA or retrospectively collected p16 staining) did not show significant differences. Overall, 5-year survival was 30% with minimal influence of the HPV positivity. CONCLUSIONS: The HPV influence on survival of OPSCC patients is not identical between populations probably due to other factors overshadowing the HPV effect. This should be taken into account when treatment or policy decisions are made in each particular setting.

Overview of 100 patients with voice prosthesis after total laryngectomy--experience of single institution.

Surgical procedures, especially total laryngectomy, used for treatment of advanced laryngeal carcinoma, have a profound adverse effect on the patient's physical, functional, and emotional health, and almost always decrease quality of life. There are three main types of voice rehabilitation after surgery. They are: esophageal speech techniques, the use of artificial larynx devices and tracheoesophageal puncture with the insertion of various types of voice prostheses. Voice prosthesis was inserted in 100 patients in the ENT Department, University Hospital Center Zagreb, from January 2004 until February 2011, and 91 of these patients were included in our study. The prosthesis was inserted secondary at 71 patients, while in other 20 it was inserted primary, i.e. immediately after laryngectomy as a part of the same procedure. Voice rehabilitation was initiated 10th day after primary insertion and 1st-3rd day after secondary insertion. The postoperative voice quality was compared with a five degree scale, which was taken from Hilger's retrospective study (2000). The rehabilitation was successful in 75.8% of our patients. Early complication rate was 4.4%, and 10.9% of patients had late complications. Statistical analysis didn't show significant differences regarding the complications rate and success rate of rehabilitation between groups of patients, formed according to age, irradiation status and timing of prosthesis insertion.

Our experience with virtual endoscopy of paranasal sinuses.

The main goal of our work was to evaluate advantages and disadvantages of virtual endoscopy (VE) techniques in routinely diagnostic and preoperative management of patients with various sinus diseases or head traumas in our practice. Fly-through algorithm was performed using an Xeon based workstation on data sets created from axial CT images acquired from 320 patients with various paranasal sinus disorders. Images were created using Siemens Somatom Emotion 16 continiously rotating helical CT scanner and archived in DICOM format. In comparison with real endoscopy, the VE has several advantages. It is completely non-invasive. It is possible to repeat the same procedure several times, therefore it may be a valuable tool for training. Interactive control of all virtual camera parameters, including the field-of-view is possible. Endoscopic viewing as opposed to real endoscopy is not restricted to the spaces defined by inner surfaces. The viewer may penetrate the walls and see the extent of lesions within and beyond the wall as well as the adjacent anatomic structures. Virtual endoscopy also has a potential to stage tumors by determining the location and the extent of transmural extension.

Application of advanced virtual reality and 3D computer assisted technologies in tele-3D-computer assisted surgery in rhinology.

The real-time requirement means that the simulation should be able to follow the actions of the user that may be moving in the virtual environment. The computer system should also store in its memory a three-dimensional (3D) model of the virtual environment. In that case a real-time virtual reality system will update the 3D graphic visualization as the user moves, so that up-to-date visualization is always shown on the computer screen. Upon completion of the tele-operation, the surgeon compares the preoperative and postoperative images and models of the operative field, and studies video records of the procedure itself Using intraoperative records, animated images of the real tele-procedure performed can be designed. Virtual surgery offers the possibility of preoperative planning in rhinology. The intraoperative use of computer in real time requires development of appropriate hardware and software to connect medical instrumentarium with the computer and to operate the computer by thus connected instrumentarium and sophisticated multimedia interfaces.

Application of novel lossless compression of medical images using prediction and contextual error modeling.

Conduction of tele-3D-computer assisted operations as well as other telemedicine procedures often requires highest possible quality of transmitted medical images and video. Unfortunately, those data types are always associated with high telecommunication and storage costs that sometimes prevent more frequent usage of such procedures. We present a novel algorithm for lossless compression of medical images that is extremely helpful in reducing the telecommunication and storage costs. The algorithm models the image properties around the current, unknown pixel and adjusts itself to the local image region. The main contribution of this work is the enhancement of the well known approach of predictor blends through highly adaptive determination of blending context on a pixel-by-pixel basis using classification technique. We show that this approach is well suited for medical image data compression. Results obtained with the proposed compression method on medical images are very encouraging, beating several well known lossless compression methods. The predictor proposed can also be used in other image processing applications such as segmentation and extraction of image regions.