Predicting locally advanced rectal cancer response to neoadjuvant therapy with 18F-FDG PET and MRI radiomics features

PURPOSE

Pathological complete response (pCR) following neoadjuvant chemoradiotherapy or radiotherapy in locally advanced rectal cancer (LARC) is reached in approximately 15-30% of cases, therefore it would be useful to assess if pretreatment of ¹⁸F-FDG PET/CT and/or MRI texture features can reliably predict response to neoadjuvant therapy in LARC.

METHODS

Fifty-two patients were dichotomized as responder (pR+) or non-responder (pR-) according to their pathological tumor regression grade (TRG) as follows: 22 as pR+ (nine with TRG = 1, 13 with TRG = 2) and 30 as pR- (16 with TRG = 3, 13 with TRG = 4 and 1 with TRG = 5). First-order parameters and 21 second-order texture parameters derived from the Gray-Level Co-Occurrence matrix were extracted from semi-automatically segmented tumors on T2w MRI, ADC maps, and PET/CT acquisitions. The role of each texture feature in predicting pR+ was assessed with monoparametric and multiparametric models.

RESULTS

In the mono-parametric approach, PET homogeneity reached the maximum AUC (0.77; sensitivity = 72.7% and specificity = 76.7%), while PET glycolytic volume and ADC dissimilarity reached the highest sensitivity (both 90.9%). In the multiparametric analysis, a logistic regression model containing six second-order texture features (five from PET and one from T2w MRI) yields the highest predictivity in distinguish between pR+ and pR- patients (AUC = 0.86; sensitivity = 86%, and specificity = 83% at the Youden index).

CONCLUSIONS

If preliminary results of this study are confirmed, pretreatment PET and MRI could be useful to personalize patient treatment, e.g., avoiding toxicity of neoadjuvant therapy in patients predicted pR-.

Transcriptomic analysis and mutational status of IDH1 in paired primary-recurrent intrahepatic cholangiocarcinoma

Background

Effective target therapies for intrahepatic cholangiocarcinoma (ICC) have not been identified so far. One of the reasons may be the genetic evolution from primary (PR) to recurrent (REC) tumors. We aim to identify peculiar characteristics and to select potential targets specific for recurrent tumors.

Eighteen ICC paired PR and REC tumors were collected from 5 Italian Centers. Eleven pairs were analyzed for gene expression profiling and 16 for mutational status of IDH1. For one pair, deep mutational analysis by Next Generation Sequencing was also carried out. An independent cohort of patients was used for validation.

Results

Two class-paired comparison yielded 315 differentially expressed genes between REC and PR tumors. Up-regulated genes in RECs are involved in RNA/DNA processing, cell cycle, epithelial to mesenchymal transition (EMT), resistance to apoptosis, and cytoskeleton remodeling. Down-regulated genes participate to epithelial cell differentiation, proteolysis, apoptotic, immune response, and inflammatory processes. A 24 gene signature is able to discriminate RECs from PRs in an independent cohort; FANCG is statistically associated with survival in the chol-TCGA dataset. IDH1 was mutated in the RECs of five patients; 4 of them displayed the mutation only in RECs. Deep sequencing performed in one patient confirmed the IDH1 mutation in REC.

Conclusions

RECs are enriched for genes involved in EMT, resistance to apoptosis, and cytoskeleton remodeling. Key players of these pathways might be considered druggable targets in RECs. IDH1 is mutated in 30% of RECs, becoming both a marker of progression and a target for therapy.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-4829-0) contains supplementary material, which is available to authorized users.

Portal vein embolization before major hepatectomy and its effects on regeneration, resectability and outcome

BACKGROUND

This study evaluated the safety of portal vein embolization (PVE), its impact on future liver remnant (FLR) volume and regeneration, and subsequent effects on outcome after liver resection.

METHODS

Records of 112 patients were reviewed. Standardized FLR (sFLR) and degree of hypertrophy (DH; difference between the sFLR before and after PVE), complications and outcomes were analysed to determine cut-offs that predict postoperative hepatic dysfunction.

RESULTS

Ten (8.9 per cent) of 112 patients had PVE-related complications. Postoperative complications occurred in 34 (44 per cent) of 78 patients who underwent hepatic resection and the 90-day mortality rate was 3 per cent. A sFLR of 20 per cent or less after PVE or DH of not more than 5 per cent (versus sFLR greater than 20 per cent and DH above 5 per cent) had a sensitivity of 80 per cent and a specificity of 94 per cent in predicting hepatic dysfunction. Overall, major and liver-related complications, hepatic dysfunction or insufficiency, hospital stay and 90-day mortality rate were significantly greater in patients with a sFLR of 20 per cent or less or DH of not more than 5 per cent compared with patients with higher values.

CONCLUSION

DH contributes prognostic information additional to that gained by volumetric evaluation in patients undergoing PVE.

Randomized clinical trial of liver resection with and without hepatic pedicle clamping

BACKGROUND

The purpose of this study was to compare the perioperative outcome of liver resection with and without intermittent hepatic pedicle clamping.

METHODS

Between June 2002 and June 2004, 126 consecutive patients with resectable liver tumours were randomized to undergo resection with (63 patients) or without (63 patients) intermittent hepatic pedicle clamping.

RESULTS

The transection time was significantly higher in the group without hepatic pedicle clamping. The blood loss per cm(2) was similar in the two groups: 2.7 ml/cm(2) in the group with versus 3.2 ml/cm(2) in group without hepatic pedicle clamping (P = 0.425). In the subset of patients with an abnormal liver, there were no differences in blood loss per transection surface: 3.1 ml/cm(2) in the group with versus 2.9 ml/cm(2) in the group without clamping (P = 0.829). The rate of blood transfusions was not higher in the non-clamping group. No differences were observed in the postoperative liver enzyme serum levels, the in-hospital mortality (one patient in each group) or the number of complications.

CONCLUSION

This study showed clearly that liver resection without hepatic pedicle clamping is safe, even in patients with a diseased liver.

Prospective randomized study of steroids in the prevention of ischaemic injury during hepatic resection with pedicle clamping

BACKGROUND

The major drawback of hepatic pedicle clamping is ischaemia-reperfusion injury with impairment of liver function. Perioperative steroid administration has been advocated to reduce liver damage. The aim of this prospective, randomized study was to determine whether steroid administration can reduce liver injury and improve short-term outcome.

METHODS

Fifty-three patients undergoing liver resection were randomized to a steroid group (group 1) or to a control group (group 2); patients in group 1 received methylprednisolone 30 mg/kg 30 min before liver resection whereas those in group 2 did not. Serum levels of interleukin (IL) 6, total bilirubin, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and prothrombin time (PT) were measured. Length of stay, and type and number of complications were recorded.

RESULTS

Serum IL-6 levels were significantly lower in the steroid group than in the control group 24 h after surgery. Steroid administration significantly modified AST, ALT and PT levels only in patients with chronic liver disease. Overall and lung-related morbidity were not significantly different between the two groups.

CONCLUSIONS

Steroid administration suppresses serum IL-6 levels, but has no effect on short-term outcome.