ESTRO 2024 - Abstract Book

S1448

Clinical - Head & neck

ESTRO 2024

Keywords: head and neck, radiation therapy, local failure

3114

Digital Poster

Patterns of Failure in Squamous Cell Carcinoma of Tongue Following Adjuvant Radiotherapy.

MARIA TARIQ 1 , BILAL MAZHAR QURESHI 1 , MAHAM KHAN 1 , RABIA TAHSEEN 1 , MARIAM HINA GHUFRAN 1 , NAWAZISH ZEHRA 1 , YUMNA JAMIL 2 , MAHAK GHULAM HUSSAIN 2 , SAROSH FAHAM KHAN 2 , AHMED NADEEM ABBASI 1 , SEHRISH ABRAR 1 , NASIR ALI 1 , ASIM HAFIZ 1

1 Aga Khan University, Oncology, Karachi, Pakistan. 2 Dow University of Health Sciences, Medicine, Karachi, Pakistan

Purpose/Objective:

To assess the frequency and features of recurrence patterns in patients with squamous cell carcinoma of tongue who underwent adjuvant radiation therapy (RT), with or without chemotherapy, at our institution.

Material/Methods:

Hospital database was reviewed and retrospectively analyzed for patients with histologically proven squamous cell carcinoma (SCC) of tongue who underwent definitive surgery followed by radiation therapy with or without chemotherapy at our institute from 2016-2021. All patients were staged according to American Joint Committee on Cancer (AJCC) 8th edition. Demographic details, treatment characteristics and clinical outcomes along with pattern of failure were recorded and analyzed.

Results:

Total Eighty-nine patients were identified with a median age of 50yr (IQR = 25 – 81). Fifty-six percent were men (n=50). Nine percent (n=8) patients had Stage I, 22% (n=20) had Stage II, 30% (n=27) Stage III, 28% (n=25) Stage IVA, while 7% (n=6) had Stage IVb. Grade 2 was most common histological grade. Perineural invasion (PNI) was identified in 41% (n=37) and 8% (n=7) had lymphovascular invasion (LVI). Forty-seven percent (n=42) patients had lymphadenopathy and extra nodal extension (ENE) was identified in 11% (n=10). Nine percent (n=8) had tumor size greater than 4cm, and 90% (n=80) had Depth of Invasion (DOI) of 4mm or greater. Concurrent chemotherapy was administered to 82% (n=73) of patients. Thirty-nine percent patients (n=35) received 70Gy in 35 fractions, 51% (n=46) received 66Gy in 33 fractions, 6patients received 55Gy in 22 fractions, and 1 patient received 50Gy in 25 fraction and 60Gy in 30 fraction each. Intensity modulated radiation therapy (IMRT) was the most commonly utilized RT technique in 47% (n=38) patients followed by volumetric arc therapy (VMAT) in 25% (n=22), and three-dimensional conformal radiation therapy in 32.5%. (n=29)