Combined value of apparent diffusion coefficient-standardized uptake value max in evaluation of post-treated locally advanced rectal cancer

AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient(ADC) and standardized uptake value(SUV)max,before and after chemo-radiation therapy,in prediction of tumor response of patients with rectal cancer,related to tumor regression grade at histology.METHODS:A total of 31 patients with biopsy proven diagnosis of rectal carcinoma were enrolled in our study.All patients underwent a whole body ^(18)FDG positron emission tomography(PET)/computed tomography(CT) scan and a pelvic magnetic resonance(MR)examination including diffusion weighted(DW) imaging for staging(PET1,RM1) and after completion(6.6 wk)of neoadjuvant treatment(PET2,RM2).Subsequently all patients underwent total mesorectal excision and the histological results were compared with imaging findings.The MR scanning,performed on 1.5 T magnet(Philips,Achieva),included T2-weighted multiplanar imaging and in addition DW images with b-value of 0 and 1000 mm^2/s.On PET/CT the SUVmax of the rectal lesion were calculated in PET1 and PET2.The percentage decrease of SUVmax(△SUV) and ADC(△ADC) values from baseline to presurgical scan were assessed and correlated with pathologic response classified as tumor regression grade(Mandard's criteria;TRG1 = complete regression,TRG5 = no regression).RESULTS:After completion of therapy,all the patients were submitted to surgery.According to the Mandard's criteria,22 tumors showed complete(TRG1) or subtotal regression(TRG2) and were classified as responders;9tumors were classified as non responders(TRG3,4 and5).Considering all patients the mean values of SUVmax in PET 1 was higher than the mean value of SUVmax in PET 2(P < 0.001),whereas the mean ADC values was lower in RM1 than RM2(P < 0.001),with a △SUV and △ADC respectively of 60.2%and 66.8%.The best predictors for TRG response were SUV2(threshold of4.4) and ADC2(1.29 × 10^(-3) mm^2/s) with high sensitivity and specificity.Combining in a single analysis both the obtained median value,the positive predictive value,in predicting the different group category response in related to TRG system,presented R^2 of 0.95.CONCLUSION:The functional imaging combining ADC and SUVmax in a single analysis permits to detect changes in cellular tissue structures useful for the assessment of tumour response after the neoadjuvant therapy in rectal cancer,increasing the sensitivity in correct depiction of treatment response than either method alone.

Any role for transarterial radioembolization in unresectable intrahepatic cholangiocarcinoma in the era of advanced systemic therapies?

Intrahepatic cholangiocarcinoma(iCCA)is recognized as the second most frequently diagnosed liver malignancy,following closely after hepatocellular carcinoma.Its incidence has seen a global upsurge in the past several years.Unfortunately,due to the lack of well-defined risk factors and limited diagnostic tools,iCCA is often diagnosed at an advanced stage,resulting in a poor prognosis.While surgery is the only potentially curative option,it is rarely feasible.Currently,there are ongoing investigations into various treatment approaches for unresectable iCCA,including conventional chemotherapies,targeted therapies,immunotherapies,and locoregional treatments.This study aims to explore the role of transarterial radioembolization(TARE)in the treatment of unresectable iCCA and provide a comprehensive review.The findings suggest that TARE is a safe and effective treatment option for unresectable iCCA,with a median overall survival(OS)of 14.9 months in the study cohort.Studies on TARE for unresectable iCCA,both as a first-line treatment(as a neo-adjuvant down-staging strategy)and as adjuvant therapy,have reported varying median response rates(ranging from 34%to 86%)and median OS(12-16 mo).These differences can be attributed to the heterogeneity of the patient population and the limited number of participants in the studies.Most studies have identified tumor burden,portal vein involvement,and the patient’s performance status as key prognostic factors.Furthermore,a phase 2 trial evaluated the combination of TARE and chemotherapy(cisplatin-gemcitabine)as a first-line therapy for locally advanced unresectable iCCA.The results showed promising outcomes,including a median OS of 22 mo and a 22%achievement in down-staging the tumor.In conclusion,TARE represents a viable treatment option for unresectable iCCA,and its combination with systemic chemotherapy has shown promising results.However,it is important to consider treatment-independent factors that can influence prognosis.Further research is necessary to identify optimal treatment combinations and predictive factors for a favorable response in iCCA patients.