Extended pathology reporting of resection specimens of colorectal liver metastases: the significance of a tumour pseudocapsule.

INTRODUCTION: The aim of this study was to analyse the influence of factors reported in the minimum histopathology dataset for colorectal liver metastases (CRLM) and other pre-operative factors compared with additional data relating to the presence of tumour pseudocapsules and necrosis on recurrence 1 year after a resection. METHODS: For a period of 14 months, extended histological reporting of CRLM specimens was performed, including the presence of pseudocapsules and necrosis in each tumour. The details of recurrence were obtained from surveillance imaging. RESULTS: In 66 patients there were 27 recurrences within 1 year. The rates were lower for patients with tumour pseudocapsules (8/27) than for patients without (19/36) (P = 0.030). Pseudocapsules were associated with a younger age (P = 0.005), nodal stage of the primary colorectal tumour (P = 0.025) and metachronous tumours (P = 0.004). In patients with synchronous disease and pseudocapsules, the recurrence rate was 2/12 compared with 13/23 patients without pseudocapsules (P = 0.026). DISCUSSION: These findings demonstrate that histological examination of resection specimens can provide significant additional prognostic information for patients after resection of CRLM, compared with clinical and radiological data. The present finding that the absence of a pseudocapsule in patients with synchronous CRLM is associated with a dramatically worse outcome may help direct patient-specific adjuvant treatment and care.

Factor H autoantibodies in membranoproliferative glomerulonephritis.

Factor H autoantibodies are found in ~10% of aHUS patients. Most are associated with complete deficiency of factor H related proteins 1/3 and bind to the C terminal recognition domain. MPGN, like aHUS, is characterised by complement activation. In this study we, therefore, examined the hypothesis that factor H autoantibodies are associated with MPGN. We screened sera from 16 MPGN patients and 100 normal controls using ELISA and detected strongly positive IgG factor H autoantibodies in 2 patients. One patient had type II (DDD) MPGN (male aged 24 yrs) with C3NeF and the other type I (female aged 26 yrs) with no detectable C3NeF. We identified the binding site of the autoantibodies using small SCR domain fragments in the ELISA and showed that the autoantibodies in both patients bound predominately to the N terminal complement regulatory domain of factor H. We measured CFHR 1/3 copy number using MLPA and showed that both patients had 2 copies of CFHR1 and 3. Finally, we examined the functionality of detected factor H autoantibodies using purified patient IgG and observed increased haemolysis when purified IgG from both patients was added to normal human sera prior to incubation with rabbit red blood cells. Thus, in a cohort of MPGN patients we have found a high titre of functionally significant factor H autoantibodies in two patients with MPGN. Antibody depleting therapy may have a role in such patients and we suggest that screening for factor H autoantibodies should be undertaken in all patients with MPGN.