Quantification of fat content in lipid-rich myxoid liposarcomas with MRI: a single-center experience with survival analysis.

OBJECTIVE: To determine the fat content of myxoid liposarcomas (MLS) on MRI and to identify any association between lipid content and survival. MATERIALS AND METHODS: The fat percentage of MLS diagnosed between January 2006 and December 2016 at a single institution was assessed by two radiologists on preoperative MR images. A Cox proportional hazard model was used to determine any association between tumor fat percentage and survival time. Tumor fat percentage was the single predictor in the model. A significance level of 0.05 was used. The Kaplan-Meier estimator was also used to provide a nonparametric estimate of the survivor function within the entire sample and within two patient subgroups consists of lipid-rich and lipid-poor tumors. Lipid-rich tumors were defined as any tumors showing more than 20% of fat on MRI. A 20% cutoff was determined arbitrarily. RESULTS: Of the 43 cases identified through retrospective review, 8 tumors demonstrated ≥10% fat on MRI, and 4 tumors demonstrated ≥20% fat (highest fat percentage, 38%). There was no significant survival difference between patients with high tumor fat, which was defined as ≥20% fat, compared with those with little to no tumor fat. CONCLUSION: Myxoid liposarcomas may demonstrate a higher fat content on MRI than has previously been reported in the literature. Increased tumor fat percentage in lipid-rich tumors was not found to be associated with increased risk of death. Radiologists must be aware of the existence of MLS lesions with higher fat content.

Extranodal extension of lymph node metastasis influences recurrence in prostate cancer: a systematic review and meta-analysis.

The extranodal extension (ENE) of nodal metastasis involves the extension of neoplastic cells through the lymph node capsule into the perinodal adipose tissue. This morphological feature has recently been indicated as an important prognostic factor in various cancer types, but its role in prostate cancer is still unclear. We aimed to clarify it, performing the first meta-analysis on this issue, comparing prognostic parameters in surgically treated, node-positive prostate cancer patients with (ENE+) vs. without (ENE-) ENE. Data were summarized using risk ratios (RRs) for number of deaths/recurrences and hazard ratios (HRs), with 95% confidence intervals (CI), for the time-dependent risk related to ENE positivity. Six studies followed-up 1,113 patients with N1 prostate cancer (658 ENE+ vs. 455 ENE-) for a median of 83 months. The presence of ENE was associated with a significantly higher risk of biochemical recurrence (RR = 1.15; 95%CI: 1.03-1.28; I2 = 0%; HR = 1.40, 95%CI: 1.12-1.74; I2 = 0%) and "global" (biochemical recurrence and distant metastasis) recurrence (RR = 1.15; 95%CI: 1.04-1.28; I2 = 0%; HR = 1.41, 95%CI: 1.14-1.74; I2 = 0%). ENE emerged as a potential prognostic moderator, earmarking a subgroup of patients at higher risk of recurrence. It may be considered for the prognostic stratification of metastatic patients. New possible therapeutic approaches may explore more in depth this prognostic parameter.

The extent of tumour fat invasion affects survival in patients with renal cell carcinoma and venous tumour thrombosis.

OBJECTIVE: • To investigate the effect of presence and extent of tumour fat invasion (TFI) - perinephric invasion (PFI), renal sinus fat invasion (RSFI) or both PFI and RSFI - on cancer-specific mortality (CSM) in patients with renal cell carcinoma (RCC) and venous tumour thrombus (VTT). METHODS: • We examined 184 consecutive patients with RCC with VTT treated with nephrectomy between 1987 and 2007. Associations with CSM were evaluated by univariable and multivariable Cox proportional hazard models. RESULTS: • Median follow up was 21 months. The 5-year CSM-free survival estimates were 75%, 36% and 20% in patients with VTT without TFI, those with VTT with PFI or RSFI, and those with VTT with both PFI and RSFI, respectively (P < 0.001). In multivariable analyses, presence of either PFI or RSFI was associated with a two-fold increased risk of CSM, whereas presence of both PFI and RSFI was associated with a three-fold increased risk of CSM, relative to VTT-only cases. • The inclusion of the variable describing the presence and extent of TFI in a base model including pT stage, Fuhrman grade and presence of nodal disease and metastatic disease significantly increased the accuracy in predicting CSM (+2.1%; P < 0.001) in patients with VTT. CONCLUSIONS: • Patients affected by RCC with VTT and TFI have a higher risk of CSM relative to cases with VTT only. Patients with both PFI and RSFI showed increased CSM compared with patients with either PFI or RSFI. • Our results suggest TFI should be accurately evaluated and included in routine pathological reports to provide better patient risk stratification.