272P Early metabolic changes in PET metrics over initial 8 weeks of treatment in patients with advanced head neck squamous cell carcinomas treated with chemotherapy

Abstract

Head and neck cancer is the most common cancer in India and the 6th most common malignant tumour worldwide. Around 60% of patients are diagnosed in advanced stage.No biomarker is available to assess the chemotherapy response. How early to assess it is not establised. So, it is of paramount to integrate molecular imaging into precision oncology care, exploring the potential of imaging as a biomarker. We conducted a prospective observational study at NCI,Nagpur,India; during 2019.The 102 advanced cases of SCC Head neck region were enrolled in study after ISC approval and informed consent.All patient’s history,addictions,clinical examination were noted. Chemotherapy: Docetaxel-Cisplatin-5FU or Paclitaxel-Carboplatin.Imaging:Baseline PET-CT scans were done followed by response evaluation scan at 2 weeks interval.The pattern of PET metrics Tumour-SUVmax and Nodal-SUVmax analysed using PERCIST criteria. P<0.05 was considered statistically significant. The mean age of study population was 48.96 yrs with male preponderance 70 (89.74%) males. The most common site involved were Buccal mucosa in 31 (39.74%) followed by tongue 20(25.64%). The 64 (82.05%) were tobacco chewer, 17 (21.79%) alcoholic and 21(26.92%) were smokers,all were in advanced stage, 6 (7.69%) stage III, 72(92%) in stage IV. The average(SD) PET-CT SUVmax value of the primary tumour during baseline, first, second and third response evaluation were 16.17(6.03), 12.53(4.94),11.38(5.47) and 12.64(7.57) respectively.As compared to baseline the change/decrease in PET-CT SUVmax values during subsequent response evaluation at 2weeks interval during chemotherapy for primary tumour and regional lymph node were statistically significant with p<0.00001. PET-CT metrics SUVmax detects metabolic response in the primary tumour and regional lymph nodes in advance head and neck squamous cell carcinoma during chemotherapy as early as 2 week with clinical corelation. It has a potential role as surrogate marker for treatment response evaluation and tailoring of the management of squamous cell carcinoma of head neck region.