ICHNO-ECHNO 2022 - Abstract Book

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ICHNO-ECHNO 2022

Connective tissue conditioning the homeostasis of human’s body is exposed to a destruction each time, regardless the type of applied radiotherapy. Collagen is the main fiber and main protein of connective tissue. PIIINP is a marker od collagen synthesis, whereas ICTP is a marker of its degradation. Matrix metalloproteinases 1, 2, 9 (MMP-1, -2, -9) are enzymes taking part in collagen turn over Materials and Methods Our study comprised 56 men aged 39-58 (average: 62.9 ± 9.3 years) with histopathologically confirmed head and neck cancer and who have had radiotherapy as a form of radical (28 men) or palliative (28 men) treatment. For each patient we calculated two differences in serum concentration of PIIINP, ICTP and MMP-1, -2, -9). D1 = concentration just before starting the radiotherapy minus concentration just after finishing the radiotherapy and presents an influence of radiotherapy. The second difference D2 = concentration 3 month after finishing the radiotherapy minus concentration just after finishing the radiotherapy and presents an influence of reconvalescence. These analysis let us see how both kinds of radiotherapy influence collagen metabolism and serum concentration of enzymes responsible for collagen turn over (D1) and how these processes can change during a reconvalescence after the radiotherapy. Results Results. After both radical and palliative radiotherapy we observed a decrease of PIIINP and increase of ICTP, MMP-1, and MMP-2. A change of serum MMP-9 concentration was opposite in two regiments of radiotherapy, it decreased during palliative, whereas increased during radical radiotherapy. During the reconvalscence period (D2) patients after palliative radiotherapy did not present any significant changes of any evaluated parameters. Patients after radical radiotherapy had an increase of PIIIPN, MMP-1, MMP-2, and a decrease of ICTP and MMP-9. Conclusion Conclusions. Our results indicate that during both palliative and radical radiotherapy treatment head and neck cancer patients a synthesis of collagen is decreased and its degradation is increased. After finishing the treatment patients undergoing radical radiotherapy present an opposite situation, an increase of collagen synthesis and a decrease of its degradation. However patients undergoing palliative radiotherapy did not present an increase of collagen synthesis during their reconvalescence. Purpose or Objective Somatostatin-analogues (SSAs), which bind to somatostatin-receptors (SST1-5), are frequently used to treat multiple tumor/cancer-pathologies. In this context, the hypermethylation of SSTs has been described in squamous cell carcinomas (SCC) of the head and neck. However, to date there are no studies describing the presence of SSTs in tumors of the oral cavity and its association with risk factors and histopathological factors of poor prognosis. Therefore, our objective was to analyze the expression patterns of SST-subtypes in tumors of the oral cavity and, to determine their associations with certain clinical/histopathological-factors in the process of tumor progression and clinical prognosis. Materials and Methods prospective observational case-control study was designed in patients diagnosed with primary oral cavity SCC. Tumor tissues and healthy-tissue (adjacent mucosa) were obtained from the same patient (n=37). mRNA was extracted and retro- transcribed, and expression levels of SST-subtypes was evaluated using a microfluidic qPCR-based array. Clinical variables from the patients (age, gender, risk factor, prognosis histopathological data, etc.) were obtained. Results Results showed significant overexpression of some of the somatostatin system components (SSTR2) in tumor tissue versus adjacent tissue. The expression of SST2 was related to the degree of cervical involvement (pN) (p <0.05). SST1, SST3, and SST5 showed a relationship with the degree of invasion of the tumor front (p <0.05). SST1, SST2, SST3 had a positive correlation (p <0.05) with the degree of peritumoral inflammatory infiltrate. SST4 showed a positive correlation with lymphovascular involvement and SST5 with perineural infiltration (p <0.05). PO-0136 Molecular and Clinical Implications of Somatostatin Receptor in Oral Cavity Squamous Cell Carcinoma A. Sanjuan Sanjuan 1 1 St John Hospital , Head and Neck Oncologic Surgery and Microvascular Reconstructive surgery, Warren, Detroit, USA

Conclusion The results of this study reveal deregulation of the expression of somatostatin system components in oral cavity carcinoma. These could be a therapeutic option to consider in the prognosis and/or diagnosis of this pathology.

PO-0137 Does intratumor heterogeneity in head and neck squamous cell carcinoma depend on tumor size?

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