Histopathological factors versus margin size in single colorectal liver metastases: Does a 1-cm margin size matter?

BACKGROUND AND OBJECTIVE: The ideal margin width for surgical resection of colorectal liver metastases has been extensively studied, but not sufficiently in accordance with other pathological factors. The aim of this study was to assess for the first time the prognostic impact of margin widths according to different prognostic pathological factors in colorectal liver metastasis. METHODS: We evaluated 101 patients with a single resected metastasis. Slides stained by HE were assessed for the presence of poorly differentiated clusters, peritumoral inflammatory infiltrate, tumor pseudocapsule, and tumor borders pattern. Overall survival, disease-free survival, and hepatic recurrence were evaluated. The pathologic factors prognostic impact was evaluated according to a (< or ⩾) 10-mm margin size. RESULTS: Factors independently associated with a shorter overall survival were absence of tumor pseudocapsule (p < 0.001) and infiltrative tumor border pattern (p = 0.019). The absence of tumor pseudocapsule was the only factor independently associated with shorter disease-free survival (p < 0.001). Hepatic recurrence was associated with infiltrative tumor border and absence of pseudocapsule. Margin width ⩾10 mm did not impact overall survival independently of the studied histological prognostic factors. CONCLUSIONS: In colorectal liver metastasis resection, the absence of tumor pseudocapsule was significantly associated with shorter overall survival and disease-free survival and hepatic recurrence. However, margins larger than 10 mm did not offer survival benefit when other pathologic negative prognostic factors were concomitantly analyzed, reinforcing the idea that biology, rather than margin size, is crucial for prognosis.

Gastric cancer molecular classification and adjuvant therapy: Is there a different benefit according to the subtype?

BACKGROUND: Gastric cancer (GC) has been defined in distinct molecular subtypes with different therapeutic implications. However, its clinical significance and prognosis regarding standard chemotherapy (CMT) remains unclear. This study aimed to analyze the impact of perioperative or adjuvant treatment among subtypes of GC. METHODS: We retrospectively evaluated all stage II/III patients with GC who underwent a curative gastrectomy. Based on immunohistochemistry and in situ hybridization techniques, GC was classified into five subtypes: Epstein-Barr virus (EBV) positive, microsatellite instability (MSI), e-cadherin aberrant, p53-aberrant, and p53-normal. RESULTS: Among the 178 CG included, 111 patients received CMT and 67 were treated with surgery alone. Survival analysis showed that p53-aberrant GC treated with CMT had better disease-free survival (DFS) compared with surgery alone (P = .001).There was no significant difference in DFS between patients who received CMT and those with surgery alone for EBV, MSI, E-cadherin, and p53-normal GC. An improvement in overall survival was observed only for E-cadherin (P = .001) and p53-aberrant (P < .001) patients who received CMT. CONCLUSIONS: CMT showed different impact on the survival of CG according to the molecular subtype. No survival benefit was observed for EBV and MSI groups who received CMT. GC with p53-aberrant had a significant benefit in survival with standard therapy.

Clinicopathological and prognostic features of Epstein-Barr virus infection, microsatellite instability, and PD-L1 expression in gastric cancer.

BACKGROUND AND OBJECTIVES: Gastric cancer (GC) has recently been categorized in molecular subtypes, which include Epstein-Barr (EBV)-positive and microsatellite instability (MSI) tumors. This distinction may provide prognostic information and identifies therapeutic targets. The aim of this study was to evaluate EBV, MSI, and PD-L1 immunoexpression in GC and its relationship with clinicopathological characteristics and patient's prognosis. METHODS: We evaluated 287 GC patients who underwent D2-gastrectomy through immunohistochemistry for DNA mismatch repair proteins and PD-L1, and in situ hybridization for EBV detection utilizing tissue microarray. RESULTS: EBV-positive and MSI were identified in 10.5% and 27% of the GCs, respectively. EBV positivity was associated to male gender (P = 0.032), proximal location (P < 0.001), undetermined Lauren type (P < 0.001), poorly differentiated histology (P = 0.043) and severe inflammatory infiltrate (P < 0.001). MSI-tumors were associated to older age (P = 0.002), subtotal gastrectomy (P = 0.004), pN0 (P = 0.024) and earlier TNM stage (P = 0.020). PD-L1-positive was seen in 8.8% of cases, with predominant expression in EBV-positive GC (P < 0.001). MSI was associated to better survival outcomes. CONCLUSION: EBV-positive GCs had increased PD-L1 expression, while MSI GC had better survival outcome. EBV and MSI subgroups are distinct GC entities, their recognition is feasible by conventional techniques, and it may help individualize follow-up and guide adjuvant therapy.

Prognostic significance of poorly differentiated clusters and tumor budding in colorectal liver metastases.

BACKGROUND: Histomorphological features have been described as prognostic factors after resection of colorectal liver metastases (CLM). The objectives of this study were to assess the prognostic significance of tumor budding (TB) and poorly differentiated clusters (PDC) among CLM, and their association with other prognostic factors. METHODS: We evaluated 229 patients who underwent a first resection of CLM. Slides stained by HE were assessed for TB, PDC, tumor border pattern, peritumoral pseudocapsule, peritumoral, and intratumoral inflammatory infiltrate. Lymphatic and portal invasion were evaluated through D2-40 and CD34 antibody. RESULTS: Factors independently associated with poor overall survival were nodules>4 (P = 0.002), presence of PDC G3 (P = 0.007), portal invasion (P = 0.005), and absence of tumor pseudocapsule (P = 0.006). Factors independently associated with disease-free survival included number of nodules>4 (P < 0.001), presence of PDC G3 (P = 0.005), infiltrative border (P = 0.031), portal invasion (P = 0.006), and absent/mild peritumoral inflammatory infiltrate (P = 0.002). PDC and TB were also associated with histological factors, as portal invasion (TB), peritumoral inflammatory infiltration (PDC), infiltrative border, and absence of tumor pseudocapsule (TB and PDC). CONCLUSIONS: This is the first study demonstrating PDC as a prognostic factor in CLM. TB was also a prognostic factor, but it was not an independent predictor of survival.

Pathological factors and prognosis of resected liver metastases of colorectal carcinoma: implications and proposal for a pathological reporting protocol.

Colorectal cancer is a leading cause of death worldwide. The liver is the most common site of distant metastases, and surgery is the only potentially curative treatment, although the recurrence rate following surgery is high. In order to define prognosis after surgery, many histopathological features have been identified in the primary tumour. In turn, pathologists routinely report specific findings to guide oncologists on the decision to recommend adjuvant therapy. In general, the pathological report of resected colorectal liver metastases is limited to confirmation of the malignancy and details regarding the margin status. Most pathological reports of a liver resection for colorectal liver metastasis lack information on other important features that have been reported to be independent prognostic factors. We herein review the evidence to support a more detailed pathological report of the resected liver specimen, with attention to: the number and size of liver metastases; margin size; the presence of lymphatic, vascular, perineural and biliary invasion; mucinous pattern; tumour growth pattern; the presence of a tumour pseudocapsule; and the pathological response to neoadjuvant chemotherapy. In addition, we propose a new protocol for the evaluation of colorectal liver metastasis resection specimens.

Prevalence of human papillomavirus types and variants and p16(INK4a) expression in head and neck squamous cells carcinomas in São Paulo, Brazil.

BACKGROUND: Human papillomavirus (HPV) prevalence in head and neck squamous cell carcinomas (HNSCC) diverges geographically. The reliability of using p16(INK4a) expression as a marker of viral infection is controversial in HNSCC. We evaluated HPV types and HPV-16 variants prevalence, and p16(INK4a) expression in HNSCC specimens provided by two different Institutions in São Paulo. METHODS: HPV DNA from formalin-fixed specimens was accessed by Inno-LiPA, HPV-16 variants by PCR-sequencing, and p16(INK4a) protein levels by immunohistochemistry. RESULTS: Overall, HPV DNA was detected among 19.4 % of the specimens (36/186). Viral prevalence was higher in the oral cavity (25.0 %, 23/92) then in other anatomical sites (oropharynx 14,3 %, larynx 13.7 %) when samples from both Institutions were analyzed together. HPV prevalence was also higher in the oral cavity when samples from both Institutions were analyzed separately. HPV-16 was the most prevalent type identified in 69.5 % of the HPV positive smaples and specimens were assigned into Asian-American (57.2 %) or European (42.8 %) phylogenetic branches. High expression of p16(INK4a) was more common among HPV positive tumors. CONCLUSION: Our results support a role for HPV-16 in a subset of HNSCC.

Carnoy's solution is an adequate tissue fixative for routine surgical pathology, preserving cell morphology and molecular integrity.

AIMS: To compare Carnoy's solution (CS) and 10% neutral buffered formalin solution (NBF) as tissue fixatives in colorectal cancer specimens. METHODS AND RESULTS: Surgical specimens from patients with colorectal cancer were analysed. Three groups were studied, as follows: group 1 consisted of 16 paired samples fixed in CS and NBF; and groups 2 and 3 consisted of 14 prospective and 80 retrospective samples, respectively, both randomized for fixation in CS or NBF. Groups 1 and 2 were analysed for amount, quality and integrity of DNA. Morphological analysis, including some of the usual special stains and polymerase chain reaction (PCR), were also performed for group 1, and Sanger sequencing for group 2. Immunohistochemical (IHC) reactions for mismatch repair proteins were studied in groups 1 and 3. Fixative performances were similar for morphology, special stains, and IHC reactions, as well as for the amount, quality and integrity of extracted DNA. PCR amplification was not possible in two cases from CS group 1. Sanger sequencing gave conclusive results for the CS samples tested. CONCLUSIONS: Carnoy's solution and NBF are equivalent fixatives for colorectal cancer specimens and are adequate for routine utilization in surgical and molecular pathology.

Decreased immunoexpression of survivin could be a potential marker in human non-alcoholic fatty liver disease progression?

BACKGROUND/AIM: Regulation of apoptosis in non-alcoholic fatty liver disease (NAFLD) has been a theme of growing debate. Although no other study assessed the role of survivin in NAFLD, its expression has been reported in hepatic carcinogenesis because of other aetiological factors with relevant discrepancies. The aim of this study was to assess the pattern of survivin immunoexpression by tissue microarray along the whole spectrum of NAFLD, including non-alcoholic steatohepatitis (NASH)-related hepatocellular carcinoma (HCC). METHODS: Liver biopsies from 56 patients with NAFLD were evaluated: 18 with steatosis, 21 non-cirrhotic NASH, 10 NASH-related cirrhosis, seven NASH-related HCC, as compared with 71 HCC related to other causes and with 12 normal livers. RESULTS: Survivin immunoexpression in NAFLD was restricted to cytoplasm and was found to be progressively lower in advanced stages, including cirrhosis and HCC: steatosis vs NASH-related cirrhosis (P=0.0243); steatosis vs NASH-related HCC (P=0.0010); NASH vs NASH-related cirrhosis (P=0.0318); and NASH vs NASH-related HCC (P=0.0007), thus suggesting a deregulation of apoptosis from NAFLD towards HCC. Interestingly, survivin immunoreactivity in NASH-related HCC was also found to be significantly lower than in HCC related to other causes (P<0.05). Remarkably, nuclear staining for survivin was not detected in any case of NAFLD, contrasting to its presence in all other cases of HCC. CONCLUSIONS: Survivin immunoexpression in NASH-related HCC is herein originally found substantially different than in HCC related to other causes, thus requiring further studies to elucidate the role of survivin in human NAFLD progression.

Prevention and reversion of nonalcoholic steatohepatitis in OB/OB mice by S-nitroso-N-acetylcysteine treatment.

OBJECTIVE: To evaluate the role oral administration of S-nitroso-N-acetylcysteine (SNAC), a NO donor drug, in the prevention and reversion of NASH in two different animal models. METHODS: NASH was induced in male ob/ob mice by methionine-choline deficient (MCD) and high-fat (H) diets. Two animal groups received or not SNAC orally for four weeks since the beginning of the treatment. Two other groups were submitted to MCD and H diets for 60 days receiving SNAC only from the 31(st) to the 60(th) day. RESULTS: SNAC administration inhibited the development of NASH in all groups, leading to a marked decrease in macro and microvacuolar steatosis and in hepatic lipid peroxidation in the MCD group. SNAC treatment reversed the development of NASH in animals treated for 60 days with MCD or H diets, which received SNAC only from the 31(st) to the 60(th) day. CONCLUSIONS: Oral administration of SNAC markedly inhibited and reversed NASH induced by MCD and H diets in ob/ob mice.

Effects of bariatric surgery on nonalcoholic fatty liver disease: preliminary findings after 2 years.

BACKGROUND AND AIM: Although nonalcoholic fatty liver disease (NAFLD) is very common among morbidly obese patients, the effect of weight loss after bariatric surgery on inflammation and fibrosis related to NAFLD is still a matter of debate. The aim of this study was to evaluate the impact of Roux-en-Y gastric bypass (RYGB) surgery on NAFLD with a follow up of 2 years. METHODS: Eighteen consecutive NAFLD patients with body mass index >40 kg/m(2) undergoing gastroplasty with RYGB were enrolled, and wedge liver biopsy was obtained at the operation. After 2 years, these patients underwent percutaneous liver biopsy. RESULTS: At baseline, 67% of patients had nonalcoholic steatohepatitis (NASH) and 33% had steatosis, according to the NASH Clinical Research Network Scoring System (NAS) for biopsy. Cirrhosis was present in 5.5% of the patients with NASH. After a mean excess weight loss of 60%, steatosis disappeared in 84% and fibrosis disappeared in 75% of the patients. Hepatocellular ballooning disappeared in 50%. A slight lobular inflammatory infiltrate remained in 81%, apparently unrelated to fatty degeneration. As liver biochemical variables had been found within normal limits in 92.3% of patients at initial biopsy, no difference was found 2 years later. Lipid profile and blood sugar plasma concentration were closer to normal in all patients after 2 years (P < 0.05). CONCLUSIONS: Aspects of NAFLD including steatohepatitis improved significantly with massive weight loss at 2 years after RYGB surgery. No patient in this series had progression of hepatic fibrosis.