Reconstructive procedures in maxillofacial oncosurgery.

OBJECTIVE: Oropharyngeal cancers are a biologically heterogenous group of tumors with diverse risk factors including tobacco, alcohol, HPV, inherited disorders, the acquired immunodeficiency of Karposi's Sarcoma and non Hodgkin's lymphoma. In the Czech Republic, oropharyngeal cancers represent around 2% of all cancers. The treatment of these tumors is long and complex. Reconstructive procedures in maxillofacial oncosurgery demand good interdisciplinary collaboration and great professional preparedness of the surgical and nursing team. Patient age and stage of disease, including the presence of metastases are of key importance. A prerequisite for the success of surgical treatment is removal of the tumor with a sufficient safety margin. Reconstructive procedures then follow. AIM: To highlight the importance of radical tumor resection and describe reconstruction of the defect in a group of our patients. METHODS AND RESULTS: From 2008 to 2013, 23 patients with oropharyngeal carcinoma underwent radical surgical removal of tumor, followed by reconstruction of postoperative defects using distant and free flaps. The histopathology showed predominantly squamous cell carcinomas and one of Merkel cell carcinoma. 16 patients had malignant disease detected in III-IV. In only 7 cases was treatment initiated in the first and second stages of the disease. In these patients, the tumors were removed with a safety margin of healthy tissue and in none, did the basic cancer recur . The postoperative course in terms of flap engraftment and overall condition of the patient was uneventful. All of these patients still enjoy a good life quality with a current mean survival in range 5 - 76 months. Radical surgical removal of a malignant tumor in the early stages of the disease is associated with fewer postoperative complications and longer survival. CONCLUSION: To avoid the risk of local and/or systemic postoperative complications, appropriate patient selection is important. Overall, the traditional, classic reconstructive procedures with the use of prostheses, in many cases is still the best option in our experience.

Odontogenic keratocysts/keratocystic odontogenic tumours: biological characteristics, clinical manifestation and treatment.

BACKGROUND: Odontogenic keratocysts (OKCs) now reclassified as Keratocystic odontogenic tumours (KCOTs) are a clinical entity with a characteristic microscopic picture, kinetic growth and biological behaviour. They arise from the proliferation of the epithelial dental lamina in both maxilla and mandible and occur in patients of all ages. 70-80% of keratocysts are found in the mandible commonly in the angle between the jaw and mandibular branch and maxillary region of the third molar. The cysts are long latent, often symptomless and may attain remarkable dimensions without significant deformation of the jaw bones. They are often found during routine dental X-ray examination. Compared to other types of jaw cyst, odontogenic cysts have a striking tendency to rapid growth and re-occurrence. AIMS: This review focuses on the biological characteristics, clinical behaviour and treatment of KCOTs. METHODS: The databases searched were the PubMed interface of MEDLINE and LILACS. RESULTS AND CONCLUSIONS: Ondontogenic keratinocysts are not currently a diagnostic problem. Orthopantomograms which are today ordinary tools of dental investigation enable diagnosis of clinically asymptomatic cystic lesions. The problem remains the optimal therapeutic approach to reduce the still high likelihood of postoperative recurrence. There is no complete consensus on the ideal operating procedure but cystectomy with delayed extirpation is favoured. An open question also remains the timeliness of screening for postoperative recurrences. Given that the first clinical manifestation of Nevoid Basal Cell Carcioma Syndome (NBCCS) may be lesions of this type, routine histopathological classification supplemented by analysis of immunophenotype should be done. Patients with proven sporadic and especially syndromic OKC should be long term screened. In patients with NBCC preventive X ray examination is recommended only once a year.

Immunohistochemical analysis of the biological potential of odontogenic keratocysts.

BACKGROUND: The aim of this study was to analyse the usefulness of detecting important apoptosis and proliferation markers in assessing the biological potential of odontogenic keratocysts (OKC) and thus selecting the optimal diagnostic algorithm for these lesions. METHODS: Indirect immunohistochemistry and relevant statistical methods were used for analysis of formalin-fixed and paraffin-embedded samples from 98 patients. RESULTS: Nevoid basal cell carcinoma syndrome (NBCCS) keratocysts were characterized by higher expression of Bcl-2, p27Kip1 and c-erbB-2 as well as by lower proliferative activity measured by Ki-67 in basal cell epithelium and by a lower inflammatory response in comparison with sporadic keratocysts. Dentigerous, radicular and non-specified odontogenic cysts differed from both NBCCS and sporadic keratocysts in a wide spectrum of apoptosis and/or cell cycle-related protein expressions, higher proliferation in the basal cell layer, and vice versa, lower proliferation in the suprabasal cell layer. CONCLUSIONS: The NBCCS keratocysts have a different immunophenotype from sporadic keratocysts and both types are distinguishable from dentigerous, radicular and non-specified odontogenic cysts. These findings confirm the separate biological potential of these lesions and the results of the immunohistochemical analysis have diagnostic and prognostic implications.

Bone defects of the facial skeleton - replacement with biomaterials.

The authors report on their experience with bone defect treatment following surgery of jaw-bone cysts. This is based on the use of cadaveric ground spongiosis saturated with tetracycline and metronidazol solution. The study shows the above mentioned material is very suitable for bone defect therapy, and cost effective. The results were verified by clinical and X-ray examination.