ICHNO-ECHNO 2022 - Abstract Book

S83

ICHNO-ECHNO 2022

Conclusion There is no established consensus yet on the best treatment strategy for OM NPC patients. Radical LR radiotherapy could prolong the overall survival. Several studies are in perspective to resolve fundamental questions in particular the best sequences treatment strategies as well as the role integration of immunotherapy to improve survival (eg. the ongoing KEYNOTE 122 trial).

Poster: Biology and molecular targeting

PO-0131 Association of Perineural Invasion with Depth of Invasion and Neck Nodes in Head & Neck Cancers

A.K. Nanda 1 , L. Pattanayak 1 , M.K. Dash 2 , S. Panda 3 , P.K. Behera 4

1 Acharya Harihar Post Graduate Institute of Cancer, Radiation Oncology, Cuttack, India; 2 S.C.B. Medical College, Social & Preventive Medicine, Cuttack, India; 3 Acharya Harihar Post Graduate Institute of Cancer, Oncopathology, Cuttack, India; 4 Acharya Harihar Post Graduate Institute of Cancer, Head & Neck Oncology, Cuttack, India Purpose or Objective • To evaluate the association of Perineural Invasion (PNI) with Depth of Invasion (DOI) in patients receiving adjuvant radiation/chemoradiation in Head and Neck Squamous Cell Carcinoma. • To also evaluate the association of Perineural Invasion with Neck Node Metastases in Head and Neck Squamous Cell Carcinoma Materials and Methods All patients with Head and Neck Squamous Cell Carcinoma receiving adjuvant radiation with or without chemotherapy during the period 2015 to 2020 in the Dept of Radiation Oncology, AH Post Graduate Institute of Cancer were accrued for the study. 201 eligible patients of histopathologically confirmed squamous cell carcinoma in Head & Neck were enrolled. With informed consent, patients were analysed in two arms, Arm A (those who were PNI positive) and Arm B (those who were PNI negative). The clinicopathological profile along with the association of Depth of Invasion (DOI) and Neck Node Metastases with PNI was studied in both arms. All patients received Radiotherapy 60 to 66 Gy in 30-33 # over 5 to 6 weeks with or without weekly Cisplatinum 40 mg /m2. The data was analysed using SPSS version 22. Results 201 eligible patients were studied; a majority of patients (n=91),45.3% were of buccal mucosa while 59 patients (29.4%) were of oral tongue. Histopathological evidence of Perineural Invasion was present in 107(53.2%) patients, Depth of Invasion of more than 4mm was seen in 165(82.1%) patients and less than or equal to 4mm was seen in 36(17.9%) patients. The number of patients who received adjuvant radiation was 69 while 121 patients received adjuvant chemoradiation. 103(51.2%) patients were found with radiologically and pathologically proven multiple neck node metastases, PNI positive patients with neck node metastases were 64patients, while PNI negative patients with neck node metastases were 39. The association of PNI with DOI was found to be statistically significant (p=0.00). Out of the 107 PNI positive patients, 101 patients had DOI more than 4mm while 6 patients had DOI less than 4mm. A total number of 165 patients had DOI more than 4mm, of which the majority of patients i.e., 101 were PNI positive. Only 64 patients were PNI negative, which shows a strong association of DOI with PNI. Similarly, the association of Perineural Invasion with Neck Node Metastases was found to be significant (p=0.013). Perineural Invasion was also found to be associated with lymphovascular space invasion (LVSI) (p=0.00) or Extracapsular Extension (ECE) (p=0.001) and statistically significant.