Gunnar Baatrup

Endorectal elastography in the evaluation of rectal tumours

Aim  Real‐time elastography visualizes tissue compliance using an ultrasound platform. Elastography has been used, particularly in the breast, to characterize indeterminate lesions on B‐mode imaging as either benign or malignant. The primary aim of this study was to assess the feasibility of routine endorectal elastography to evaluate rectal neoplasia. The secondary aim was to correlate elastography data with histopathological end‐points.

Transanal endoscopic microsurgery in 143 consecutive patients with rectal adenocarcinoma: results from a Danish multicenter study.

Objective  The long‐term results are presented on total survival, cancer‐specific survival and recurrence in 143 consecutive patients treated with transanal endoscopic microsurgery (TEM) for adenocarcinoma of the rectum.

Complement activation in plasma before and after Infliximab treatment in Crohn disease

Background: Crohn disease is characterized by up‐regulated intestinal inflammation mainly caused by increased tumour necrosis factor alpha (TNF‐α) levels. However, the complement system (C) may also have a role in maintaining inflammation. Methods: Plasma from 26 patients with Crohn disease complicated by fistulizing ano‐rectal disease was collected before and after three Infliximab infusions (5 mg kg −1 ). Results: Before treatment, the C3‐activation capacities (C3‐AC) in plasma from patients with Crohn disease were comparable with values obtained from healthy controls. The classical C pathway‐mediated C3‐AC, mannan‐binding lectin C4‐AC, leucocyte count, C‐reactive protein concentration and Crohn Disease Activity Index decreased significantly 8 weeks after the first infusion of Infliximab (P < 0.04, Wilcoxon test). Conclusions: Before treatment, all three C pathways were within the normal range in plasma from patients with Crohn disease; the decrease observed in the classical pathway‐mediated C3‐AC after treatment with Infliximab reflects a general down‐regulation in immune activation.

Preoperative staging and treatment options in T1 rectal adenocarcinoma

Background. Major rectal resection for T1 rectal cancer offers more than 95% cancer specific five-year survival to patients surviving the first 30 days after surgery. A significant further improvement by development of the surgical technique may not be possible. Improvements in the total survival rate have to come from a more differentiated treatment modality, taking patient and procedure related risk factors into account. Subgroups of patients have operative mortality risks of 10% or more. Operative complications and long-term side effects after rectum resection are frequent and often severe. Results. Local treatment of T1 cancers combined with close follow-up, early salvage surgery or later radical resection of local recurrences or with chemo-radiation may lead to fewer severe complications and comparable, or even better, long-term survival. Accurate preoperative staging and careful selection of patients for local or non-operative treatment are mandatory. As preoperative staging, at present, is not sufficiently accurate, strategies for completion, salvage or rescue surgery is important, and must be accepted by the patient before local treatment for cure is initiated. Recommendations. It is recommended that polyps with low-risk T1 cancers should be treated with endoscopic snare resection in case of Haggitts stage 1 or 2. TEM is recommended if resection margins are uncertain after snare resection for Haggitts stage 3 and 4, and for sessile and flat, low- risk T1 cancers. Average risk patients with high-risk T1 cancers should be offered rectum resection, but old and comorbid patients with high-risk T1 cancers should be treated individually according to objective criteria as age, physical performance as well as patients preference. All patients treated for cure with local resection or non-surgical methods should be followed closely.

Complement activation mediated by mannan-binding lectin in plasma from healthy individuals and from patients with SLE, Crohn's disease and colorectal cancer. Suppressed activation by SLE plasma.

We have developed a method for quantitating mannan‐binding lectin (MBL)‐induced activation of the complement system (MBL‐C4‐AC) in human plasma. This method and an assay for MBL concentration were applied to plasma samples from healthy individuals and patients with systemic lupus erythematosus (SLE), Crohns disease (CD) and colorectal cancer (CRC). The MBL concentration was measured by an enzyme‐linked immunosorbent assay (ELISA) using monoclonal anti‐MBL‐antibodies and MBL‐C4‐AC by an ELISA using solid‐phase mannan, incubating with plasma samples and quantitating the complement (C) activation by the use of antibodies against the C split‐products C4b/C4c. The MBL concentration was nonsignificantly elevated in plasma from SLE‐patients, whereas MBL‐C4‐AC was suppressed ( P < 0.04). There was no correlation between MBL concentration and MBL‐C4‐AC in plasma from SLE‐patients. In contrast, a significant correlation was found between the MBL concentration and MBL‐C4‐AC in plasma from healthy individuals. The C4 concentration was significantly reduced ( P < 0.002) in plasma from the SLE patients and showed a significant correlation to MBL‐C4‐AC. The MBL‐C4‐AC assay was highly effective in discriminating the SLE patients from the other patient groups and healthy individuals.

The Attachment of Serum-and Plasma-Derived C3 to Solid-Phase Immune Aggregates and its Relation to Complement-Mediated Solubilization of Immune Complexes

The interaction between immune aggregates and complement (C) was investigated Solid‐phase immune aggregates were prepared by coating microwells with heat‐aggregated bovine serum albumin (BSA) followed by rabbit anti‐BSA antibody. The immune aggregates were reacted with human serum or citrated plasma al 370C. The binding of C3 components was investigated with biotinylated F(ab′)2 antibodies In C3c and C3d and avidin‐coupled alkaline phosphatase. The form of the incorporated C3. whether C3b‐iC3b or C3dg. can be deduced from the response with these two antibodies. The maximal binding of C3b‐iC3h to the immune aggregates was observed within 5 min of incubation with serum or citrated plasma The conversion to C3dg was evident by a decrease in bound anti‐C3c concomitant with increasing anti C3d reactivity within about 10min of incubation. When the classical C pathway activation was inhibited, the binding of C3b‐iC3b was delayed by 20–30 min. whereas stopping of the alternative pathway did not influence the initial kinetics of the reaction. The addition of human red blood cells had no measurable influence on the degradation of bound C3b‐iC3b.125I‐lebelled anti‐BSA antibody bound to the solid‐phase BSA was not released during the C3 incorporation. The incorporation of C3b into the immune aggregates was mediated equally well by serum and by citrated plasma. The incorporation of C3b‐iC3b into immune complexes (IC) is thought to be responsible for the C‐mediated solubilization (CMS) of IC. Citrated plasma, however, exerted no CMS capacity when measured by a radiometric assay, The CMS capacity of serum was inhibited by citrate, but could then be restored by adding Ca2+ and Mg2+, whereas no CMS could be demonstrated with citrated plasma to which divalent metal ions were added.

Long-term results of a phase II trial of high-dose radiotherapy (60 Gy) and UFT/l-leucovorin in patients with non-resectable locally advanced rectal cancer (LARC)

Background. Preoperative radiochemotherapy is a cornerstone in patients with non- resectable locally advanced rectal cancer (LARC). To improve outcome (number of R0 resections and survival) high-dose radiotherapy (RT) was combined with oral UFT/l-leucovorin to allow tumour regression before radical intended surgery. Methods. Pelvic RT was delivered with megavoltage photons using a 5 field technique. RT was CT-based, given 5 days a week through one posterior field and two lateral fields (48.6 Gy/27 fractions) to encompass the primary tumour and the regional lymph nodes. In addition, the tumour bed received a concurrent boost (5.4 Gy/27 fractions) and a final boost (6 Gy/3 fractions); thus GTV received 60 Gy/30 fractions. Concurrent with RT patients received a daily dose of oral UFT 300 mg/m2 plus l-leucovorin 22.5 mg 5/7days (divided in three doses). Results. From September 2000 to November 2004, 52 patients (median age 60 years (32–83); median PS 0 (0–2)) with LARC (36 primary, 16 recurrent) were included in this phase II study. All but three patients received the planned 60 Gy, median duration of RT was 42 days (25–49). Toxicity was very modest; only four patients had a dose reduction of UFT. No hematological toxicity of clinical significance was seen. Non-hematological toxicity grade 1 (GI-toxicity, fatigue and/or dysuria) was frequently observed but only four patients experienced grade 3 toxicity (diarrhoea and/or nausea/vomiting). Forty patients (77%) were operated (30 R0, 5 R1, 5 R2) median 55 days (27–112) after completion of RT. Seven (13%) patients had a pathological complete response (pCR). Thirty-one patients (60%) died after median 25.4 months (1.6–45.2 months). Twenty-one patients (40%) are still alive June 2007. Conclusions. Preoperative high-dose RT and concomitant UFT produces major regression in most patients with non-resectable LARC and thus a good chance of cure.

Characterization of a Lectin in Human Plasma Analogous to Bovine Conglutinin

The structural characteristics of a human plasma protein analogous to bovine conglutinin were studied. The protein was previously found to bind to complement‐reacted IgG in a calcium‐dependent and N‐acetyl‐D‐glucosamine‐inhibitable manner and it further shows cross‐reactivity with anti‐bovine conglutinin antibody. By gel permeation chromatography the conglutinin activity in human plasma was localized to fractions containing proteins of Mj at around 700,000. The conglutinin was localized by one ELISA for antigen determinants and by another for biological activity. When analysed by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE) under non‐reducing conditions these fractions were shown to contain proteins of about 300,000. When human conglutinin‐like protein, partially purified by affinity chromatography, was analysed unreduced by SDS‐PAGE followed by western blotting, the cross‐reacting anti‐bovine conglutinin antibody bound to a protein with an Mr of 330,000. When the sample was reduced and alkylated before electrophoresis a band of 66,000 was immunostained. The 330,000 and 66,000 proteins were shown to be collagenase sensitive. 125I‐iC3b was seen to bind to the 330,000 band when incubated with western blots of partially purified human conglutinin.

Strain assessment in surgically resected inflammatory and neoplastic bowel lesions.

PURPOSE To investigate whether ultrasound-based strain imaging can discriminate between colorectal adenocarcinomas and stenotic Crohns lesions in newly resected surgical specimens. MATERIALS AND METHODS Resected surgical specimens from 27 patients electively operated for colorectal tumors or stenotic lesions from Crohns disease were prospectively examined with ultrasonography using a Hitachi HV 900 US scanner with real-time elastography (RTE). Three different methods were applied to assess tissue strain: A four-level categorical visual classification, a continuous visual analog scale (VAS, 0 - 100) and a strain ratio (SR) measurement between the lesion and surrounding reference tissue. The imaged sections were marked and subsequently examined by a pathologist. Results from RTE were evaluated according to diagnosis, degree of fibrosis, inflammatory parameters, tumor stage and grade. RESULTS 16 sections from Crohns lesions, 18 sections from adenocarcinomas and 4 sections from adenomas were examined. Both adenocarcinomas and Crohns lesions were found to be harder than the surrounding tissue, but they could not be discriminated from each other by any of the strain imaging evaluation methods. All adenocarcinomas had significantly higher strain ratios than adenomas. The categorical classification differentiated poorly between Crohns lesions, adenocarcinomas and adenomas. Categorical evaluation and VAS score showed fair interobserver agreement. SR measurements provided semi-quantitative strain data and added improved information about elasticity properties, despite substantial intra-observer variation. CONCLUSION Sonoelastography with SR measurements and visual evaluation of strain differences could not differentiate stenotic Crohns lesions from adenocarcinomas in resected bowel specimens. A small number of adenomas were found to be significantly softer than adenocarcinomas using the same evaluation methods. The tumor stage or grade did not have a significant impact on the elastography results.

Benign rectal strictures managed with transanal resection – A novel application for transanal endoscopic microsurgery

Objective  Six cases of management of rectal strictures by transanal endoscopic microsurgery (TEM) are described.