ICHNO-ECHNO 2022 - Abstract Book

S82

ICHNO-ECHNO 2022

PO-0129 Submandibular gland invasion in oral cavity carcinoma: preliminary results from a multicenter study

O. Iocca 1 , P. Di Maio 2 , S. Rubattino 1 , L. Sedran 1 , F. Volpe 3 , G. Petruzzi 4 , G. Ramieri 1 , C. Copelli 1

1 University of Turin, Maxillofacial Surgery, Torino, Italy; 2 Giuseppe Fornaroli Hospital, ASST Ovest Milanese , Otolaryngology - Head and Neck Surgery, Magenta , Italy; 3 University of Turin, Maxillofacial Surgery, Turin, Italy; 4 Istituto Tumori Regina Elena, Otolaryngology - Head and Neck Surgery, Roma, Italy Purpose or Objective Investigate the rate of submandibular gland (SMG) involvement in primary squamous cell carcinoma of the oral cavity and analyze the potential predictors of invasion Materials and Methods Data collected from five tertiary care centers in Europe were retrospectively collected. Inclusion criteria were defined as follows: adult patients who underwent neck dissection for primary squamous cell cell carcinoma of the oral cavity, no history of radiotherapy or chemotherapy for head and neck neoplasms before surgery, inclusion of the level IB in the neck dissection, availability of a detailed pathology report. Univariate and multivariate analyses were conducted to understand the rate of SMG invasion and the predictors of invasion. Results Preliminary analysis performed on data obtained by two participating centers allowed the analysis of 260 patients. The rate of SMG invasion was 3/260 1.1% (95% CI 0.7-1.5). Direct invasion was the only way of spread (100% of cases). Multivariate analysis showed that advanced stage, floor of mouth localization, and pN+ status were positive predictors of invasion (p<0.0001). Conclusion The SMG also has close proximity with level I lymph nodes. Due to this, traditional neck dissection techniques - such as radical/modified radical neck dissection or selective neck dissection - typically involve SMG excision. The gland's involvement is possible despite its relative infrequence. Therefore, clinicians involved in the management of oral cavity carcinoma should be aware that SMG invasion is a potential occurrence. Some authors advocate for SMG preservation during neck dissection, given that xerostomia is one of the most detrimental side effects of cancer therapy. In fact, SMG preservation during neck dissection might increase the quality of life of cancer survivors, but a careful risk/benefit analysis should be performed. The same considerations are valid when considering SMG sparing in patients undergoing radiotherapy. Our analysis can help clinicians understand which patients are at high risk for SGM invasion, especially those suffering from floor of mouth cancer, advanced stage tumors, and pN+ patients as they seem to have the highest invasion risk. 1 Salah Azaiez Institute, Radiation Oncology, Tunis, Tunisia; 2 Salah Azaiez Institute, Radiation Oncology , Tunis, Tunisia; 3 Salah Azaiez Institute , Radiation Oncology, Tunis , Tunisia Purpose or Objective Nasopharyngeal carcinoma (NPC) accounts for 0.7% of all new cancer cases and for 0.8% of all cancer deaths occurring across the world. Due to the concealed location of the tumor, most patients are locally advanced or distantly metastatic at the time of the initial diagnosis. The incidence of synchronous metastasis in NPC range from 4% to 10%. Oligometastatic (OM) NPC is a distinctive subset with better prognosis. Increasing evidences support that prolonged overall survival (OS) is possible for patients undertaking appropriate treatments. The aim of our study is to describe the epidemiological and clinical features of OM entity and to highlight the role of locoregional (LR) treatment into the primary site. Materials and Methods From January 2009 to December 2019, we enrolled 24 OM patients with histologically confirmed nasopharyngeal undifferentiated carcinoma. We have considered OM as a limited number of organ and site involvement (e.g., 1–2 organ metastases or < 5 metastatic lesions). The TNM classification used was the 8th edition published by the American Joint Committee on Cancer (AJCC). We only included patients who underwent a first line of chemotherapy with good or stable response of the lesions according to RECISTv1.1. Only a good Karnofsky performance status (KPS >70) were selected for LR treatment with radiotherapy and concomitant chemotherapy. Results The median age was 43.4 years. The sex-ratio was 3. Tumor were classified as T4 and T3 respectively in 50% and 16.7% of cases. Regional Lymph nodes invasion were classified on N3, N2 and N1 in 50%, 30% and 20% respectively. Bone metastases were the most common site (68.4%), followed by pulmonary metastases (21%) and liver metastases (15.8%). Sixty-two percent of patients had a single metastasis. Four to six cycles of 5FU-cisplatin were completely administered (41.6%). Partial response was noted in 50% of cases. Locoregional radiation therapy with curative intent was delivered at the dose of 70 Gy on the tumor and 54 Gy on prophylactic areas. Metastatic sites were irradiated in only four patients. Concurrent chemotherapy were conducted in all patients. Nevertheless, 16.7% of patient developed grade 3-4 toxicity. Locoregional treatment response was complete in 40% of cases. After a median follow-up of 40 months, the 1- and 3-year overall survival rates was 70% and 40%, respectively while the 1 and 3-year progression-free survival was 60% and 30%, respectively. PO-0130 Locoregional treatment for oligo-metastatic nasopharyngeal carcinoma H. chahdoura 1 , A. Mousli 1 , R. Abidi 2 , E. Kouti 1 , A. Yousfi 1 , K. Mahjoubi 3 , C. Nasr 1