Prognostic impact of tumour burden assessed by metabolic tumour volume on FDG PET/CT in anal canal cancer.

PURPOSE: The aim of this study was to confirm the prognostic value of metabolic tumour volume (MTV) at the primary site on initial work-up FDG PET/CT in patients with squamous cell carcinoma (SCC) of the anal canal. METHODS: Patients with a recent diagnosis of SCC of the anal canal without metastases undergoing PET/CT for initial work-up and treated with (chemo)radiotherapy were retrospectively reviewed. Computer-aided MTV and SUVmax were determined. Survival rates were estimated using the Kaplan-Meier method. Cox regression analysis was used to evaluate prognostic variables of progression-free survival and overall survival (OS). RESULTS: The study group comprised 75 patients who had an initial work-up PET/CT. Five patients (6.7 %) had stage I disease, 22 (29.3 %) stage II disease, 20 (26.7 %) stage IIIA disease, and 28 (37.3 %) stage IIIB disease. Median follow-up was 51 months (range 10 - 117 months). Global 4-year OS was 82.7 %, ranging from 100 % in patients with stage I disease to 75 % in patients with stage IIIB disease. MTV at the primary site was significantly and independently correlated with OS (p < 0.05), as patients with MTV less than 7 cm3 had a better prognosis. SUVmax was not correlated with survival parameters. Metabolic involvement of the inguinal lymph nodes was also correlated with a poor outcome in the univariate analysis (p < 0.05). CONCLUSION: MTV at the primary site is a prognostic biomarker in anal canal cancer. Hypermetabolic inguinal lymph nodes also appear to be correlated with survival.

Initial MRI findings predictive of a pathological complete response to neoadjuvant treatments in HER2-positive breast cancers.

PURPOSE: This study aimed to determine if initial MRI findings could predict a pathological complete response (pCR) following neoadjuvant systemic therapy (NST) in HER2-positive breast cancers. METHODS: The study retrospectively included 111 patients (Center 1, training set) and 71 patients (Center 2, validation set) with HER2-positive cancer who underwent NST. Initial clinicopathological data and MRI findings were recorded. Continuous variables were analyzed using the Mann-Whitney and Student's t-tests, while categorical variables were analyzed using the χ2 or Fisher's exact test. Univariate analysis was conducted to determine the associations between these variables and pathological complete response (pCR), defined as the absence of invasive malignant cells in the breast and lymph nodes. Interobserver reproducibility was assessed for associated non-mass enhancement (NME) parameter by analyzing 50 MR studies (intraclass correlation coefficient). RESULTS: pCR was achieved in 67 patients, 51 (46 %) from Center 1 and 16 (23%) from Center 2 (p = 0.003), with significant differences between Centers 1 and 2 in tumor-infiltrating lymphocyte levels and lymphovascular invasion (p < 0.001). The initial presence of suspicious associated NME was the only significant parameter predictive of pCR (p < 0.001 for Center 1 and 0.04 for Center 2). The inter-observer reproducibility for this MRI feature was good, with an intraclass correlation coefficient of 0.872 (95 % CI: 0.73-1.00). CONCLUSION: The presence of suspicious associated NME in HER2-positive cancers on the initial MRI study was predictive of achieving pCR after NST. This significant preliminary finding warrants confirmation through prospective multicenter studies.