Long-Term Effects of Omitting Antibiotics in Uncomplicated Acute Diverticulitis.

BACKGROUND: Traditionally uncomplicated acute diverticulitis was routinely treated with antibiotics, although evidence for this strategy was lacking. Recently, two randomized clinical trials (AVOD trial and DIABOLO trial) published short-term results of omitting antibiotics compared to routine antibiotic treatment. Both showed no significant differences regarding recovery from the initial episode, as well as rates of complicated or recurrent diverticulitis and sigmoid resection. However, both studies showed a trend of higher rates of sigmoid resection in the observational groups. Here, the long-term effects of omitting antibiotics in first episode uncomplicated acute diverticulitis were assessed. METHODS: A total of 528 patients with CT-proven, primary, left-sided, uncomplicated acute diverticulitis were randomized to either an observational or an antibiotic treatment strategy (DIABOLO trial). Outcome measures were complicated diverticulitis, recurrent diverticulitis and sigmoid resection at 24 months' follow up. Differences between the groups were explored and risk factors were identified using multivariable logistic regression. RESULTS: Complete case analyses showed no difference in rates of recurrent diverticulitis (15.4% in the observational group versus 14.9% in the antibiotic group; p = 0.885), complicated diverticulitis (4.8% versus 3.3%; p = 0.403) and sigmoid resection (9.0% versus. 5.0%; p = 0.085). Young patients (<50 years) and patients with a pain score at presentation of 8 or higher on a visual analogue pain scale were at risk for complicated or recurrent diverticulitis. In this multivariable analysis, treatment type (with or without antibiotics) was not an independent predictor for complicated or recurrent diverticulitis. CONCLUSION: Omitting antibiotics in the treatment of uncomplicated acute diverticulitis did not result in more complicated diverticulitis, recurrent diverticulitis or sigmoid resections at long-term follow up. As the DIABOLO trial was not powered for these secondary outcome measures, some uncertainty remains whether (small) non-significant differences could be true associations.

Randomized clinical trial of observational versus antibiotic treatment for a first episode of CT-proven uncomplicated acute diverticulitis.

BACKGROUND: Antibiotics are advised in most guidelines on acute diverticulitis, despite a lack of evidence to support their routine use. This trial compared the effectiveness of a strategy with or without antibiotics for a first episode of uncomplicated acute diverticulitis. METHODS: Patients with CT-proven, primary, left-sided, uncomplicated, acute diverticulitis were included at 22 clinical sites in the Netherlands, and assigned randomly to an observational or antibiotic treatment strategy. The primary endpoint was time to recovery during 6 months of follow-up. Main secondary endpoints were readmission rate, complicated, ongoing and recurrent diverticulitis, sigmoid resection and mortality. Intention-to-treat and per-protocol analyses were done. RESULTS: A total of 528 patients were included. Median time to recovery was 14 (i.q.r. 6-35) days for the observational and 12 (7-30) days for the antibiotic treatment strategy, with a hazard ratio for recovery of 0·91 (lower limit of 1-sided 95 per cent c.i. 0·78; P = 0·151). No significant differences between the observation and antibiotic treatment groups were found for secondary endpoints: complicated diverticulitis (3·8 versus 2·6 per cent respectively; P = 0·377), ongoing diverticulitis (7·3 versus 4·1 per cent; P = 0·183), recurrent diverticulitis (3·4 versus 3·0 per cent; P = 0·494), sigmoid resection (3·8 versus 2·3 per cent; P = 0·323), readmission (17·6 versus 12·0 per cent; P = 0·148), adverse events (48·5 versus 54·5 per cent; P = 0·221) and mortality (1·1 versus 0·4 per cent; P = 0·432). Hospital stay was significantly shorter in the observation group (2 versus 3 days; P = 0·006). Per-protocol analyses were concordant with the intention-to-treat analyses. CONCLUSION: Observational treatment without antibiotics did not prolong recovery and can be considered appropriate in patients with uncomplicated diverticulitis. Registration number: NCT01111253 (http://www.clinicaltrials.gov).

Breast cancer response to neoadjuvant chemotherapy: predictive markers and relation with outcome.

The aim of this study was to provide a better insight into breast cancer response to chemotherapy. Chemotherapy improves outcome in breast cancer patients. The effect of cytotoxic treatment cannot be predicted for individual patients. Therefore, the identification of tumour characteristics associated with tumour response and outcome is of great clinical interest. We studied 97 patients, who received anthracycline-based neoadjuvant chemotherapy. Tumour samples were taken prior to and after chemotherapy. We quantified the response to chemotherapy clinically and pathologically and determined histological and molecular tumour characteristics. We assessed changes in the expression of Bcl-2, ER, P53 HER2 and Ki-67. Association with response and outcome was tested for all parameters. The experimental results showed 15 clinical (17%) and three (3%) pathological complete remissions. There were 18 (20%) clinical vs 29 (33%) pathological nonresponders. The expression of most markers was similar before and after chemotherapy. Only Ki-67 was significantly decreased after chemotherapy. Factors correlated with response were: large tumour size, ER negativity, high Ki-67 count and positive P53 status. Tumour response and marker expression did not predict disease-free or overall survival. In conclusion, clinical and pathological response assessments are poorly associated. Proliferation decreases significantly after chemotherapy. ER negativity and a high proliferation index are associated with better response. HER2 status does not predict response, and outcome is not related to tumour response.

Randomized trial of high-dose chemotherapy and hematopoietic progenitor-cell support in operable breast cancer with extensive lymph node involvement: final analysis with 7 years of follow-up.

BACKGROUND: The aim of this study was to present an update of overall (OS) and disease-free survival (DFS) and to evaluate the correlation between outcome and pathological findings at surgery in a randomized trial of high-dose chemotherapy following neoadjuvant chemotherapy and surgery in high-risk breast cancer patients. PATIENTS AND METHODS: Ninety-seven women <60 years of age with breast cancer and extensive axillary lymph node involvement received three courses of FE120C (5-fluorouracil 500 mg/m2, epirubicin 120 mg/m2, cyclophosphamide 500 mg/m2) followed by surgery. Eighty-one patients were randomized to receive either a fourth FE120C course alone or a fourth FE120C course followed by high-dose chemotherapy (cyclophosphamide 6 g/m2, thiotepa 480 mg/m2, carboplatin 1600 mg/m2). We performed a univariate analysis on possible prognostic factors and analyzed the sites of relapse. RESULTS: After a median follow-up of 6.9 years, 47 (48%) patients were alive, of whom 36 (38%) were without disease. Sixty patients relapsed after treatment. One patient died of myelodysplastic syndrome, without a relapse. In intention-to-treat analysis, the 5-year DFS rates were 47.5% in the conventional treatment arm and 49% in the high-dose arm, and the 5-year OS rates were 62.5% and 61%, respectively. In the univariate analysis, the clinical T-stage before chemotherapy and the number of tumor-positive axillary lymph nodes after induction chemotherapy (P = 0.027) were significant prognostic factors for OS. The same factors (both P = 0.06) plus the estrogen receptor (P = 0.08) were borderline significant factors for DFS. CONCLUSIONS: After a median follow-up of 6.9 years there was no difference in OS or DFS rates between the two treatment groups. The number of tumor-positive axillary lymph nodes after induction chemotherapy and the clinical T-stage before chemotherapy were significant factors for OS.

Determining MDR1/P-glycoprotein expression in breast cancer.

The mechanism of chemotherapy resistance in breast cancer is unresolved. MDR1/P-glycoprotein (P-Gp) over-expression confers multidrug resistance in vitro and might play a role in clinical breast cancer. Studies using clinical samples have yielded conflicting results. MDR1/P-Gp mRNA expression was determined relative to the expression in normal human liver using TaqMan real-time RT-PCR (corrected for expression of the housekeeping gene PBGD). Immunohistochemistry (IHC) was performed with monoclonal antibodies against P-Gp (JSB1, C219). The positive control was SW1573/2R160, the intermediate control SW1573 and the negative control GLC4/ADR. We assayed 9 breast-cancer cell lines by RT-PCR and IHC, 52 carcinoma samples by RT-PCR and 168 samples by IHC. SW1573/2R160 contained high levels of MDR1/P-Gp mRNA (1.0, equal to liver) and showed strong membranous staining. Expression of MDR1/P-Gp mRNA in SW1573 (0.05) and GLC4/ADR (3.2 x 10(-5)) was not detectable by IHC. Very low levels of MDR1/P-Gp mRNA were measured in breast-cancer cell lines (mean 3.1 x 10(-4), range 1 to 12 x 10(-4)), but P-Gp was not detected by IHC. In 25 specimens from chemotherapy-naive patients, MDR1/P-Gp mRNA levels varied from 1 to 11 x 10(-2) (mean 3.9 x 10(-2)). In sections of 80 chemotherapy-naive tumors, no membrane-bound staining was observed in the tumor cells. Tumors of 27 anthracycline-treated patients had comparable MDR1/P-Gp mRNA expression levels (mean 5.4 x 10(-2)). P-Gp was undetectable in 88 tumor samples of patients who had received anthracycline-based chemotherapy. In breast cancer, MDR1/P-Gp mRNA is low or absent and P-Gp levels in cancer cells are too low to detect by IHC. Chemotherapy exposure does not result in detectable MDR1/P-Gp over-expression.

Frozen section investigation of the sentinel node in malignant melanoma and breast cancer.

BACKGROUND: Intraoperative frozen section investigation allows immediate regional lymph node dissection when the sentinel node contains tumor. The purpose of this study was to determine the sensitivity of frozen section diagnosis of the sentinel node in melanoma and breast cancer patients. METHODS: A total of 177 sentinel nodes from 99 melanoma patients and 444 lymph nodes from 262 breast cancer patients were assessed by frozen section investigation. Nodes were bisected, and a complete cross-section was obtained for frozen section. Step sections at three levels were made of the remaining lymphatic tissue and were stained with hematoxylin and eosin and S100/HMB45 (melanoma) or CAM5.2 (breast cancer) to obtain a final pathological diagnosis. RESULTS: Frozen section investigation revealed metastases in 8 of 17 node-positive melanoma patients (47%). Seventy-one of 96 breast cancer patients (74%) with lymph node metastases were identified with frozen section. The specificity was 100% and 99%, respectively. CONCLUSION: The sensitivity of intraoperative frozen section investigation of sentinel nodes was 47% in melanoma patients and 74% in breast cancer patients. Frozen section examination allows immediate axillary lymph node dissection in the majority of node-positive breast cancer patients. Frozen section analysis is not recommended in patients with melanoma.

Subcellular localization and distribution of the breast cancer resistance protein transporter in normal human tissues.

High expression of the Breast Cancer Resistance Protein (BCRP) gene has been shown to be involved in resistance to chemotherapeutic drugs. Knowledge of the localization of BCRP protein in normal tissues may help unravel the normal function of this protein. Therefore, we characterized the tissue distribution and cellular localization of BCRP in frozen sections of normal human tissues. For this purpose, we used the recently described monoclonal antibody BXP-34 and another independently developed monoclonal antibody directed against BCRP, BXP-21. Both monoclonal antibodies show specific BCRP plasma membrane staining on cytospins obtained from topotecan- or mitoxantrone-selected cell lines, as well as from BCRP-transfected cell lines. Immunoprecipitation experiments using either BXP-21 or BXP-34 yielded a clear M(r) 72,000 BCRP band from BCRP-overexpressing tumor cells. In the topotecan-selected T8 and mitoxantrone-selected MX3 tumor cell lines, BCRP turned out to be differentially glycosylated. In contrast to BXP-34, BXP-21 is able to detect the M(r) 72,000 BCRP protein on immunoblots and is reactive with BCRP in formalin-fixed, paraffin-embedded tissues. Using BXP-21 and BXP-34, prominent staining of BCRP was observed in placental syncytiotrophoblasts, in the epithelium of the small intestine and colon, in the liver canalicular membrane, and in ducts and lobules of the breast. Furthermore, BCRP was present in veinous and capillary endothelium, but not in arterial endothelium in all of the tissues investigated. In the tissues studied, the mRNA levels of BCRP were assessed using reverse transcription-PCR, and these corresponded with the levels of BCRP protein estimated from immunohistochemical staining. The presence of BCRP at the placental syncytiotrophoblasts is consistent with the hypothesis of a protective role of BCRP for the fetus. The apical localization in the epithelium of the small intestine and colon indicates a possible role of BCRP in the regulation of the uptake of p.o. administered BCRP substrates by back-transport of substrate drugs entering from the gut lumen. Therefore, it may be useful to attempt to modulate the uptake of p.o. delivered BCRP substrates, e.g., topotecan or irinotecan, by using a BCRP inhibitor. Clinical trials testing this hypothesis have been initiated in our institute.

Chest wall resection in the treatment of locally recurrent breast carcinoma: indications and outcome for 44 patients.

BACKGROUND: Locoregional recurrence after initial treatment of breast carcinoma occurs in up to 35% of patients. In selected patients, chest wall resection (CWR) can be performed to regain local control. Extensive surgery is justifiable only if good palliation and possibly a better prognosis can be offered and the morbidity is limited. METHODS: The authors conducted a retrospective review of the medical records of 44 females with locally recurrent breast carcinoma who underwent chest wall resection between 1979 and 1995 at the Netherlands Cancer Institute. Preoperative patient characteristics were recorded, and complications were scored. Analysis was made of disease free and overall survival after resection as well as the influence of presumed prognostic factors on survival. The median duration of follow-up was 3.2 years. RESULTS: The mean patient age at diagnosis of breast carcinoma was 47.5 years. The median interval between first treatment and relapse was 3.9 years. Thirty patients (68%) underwent CWR with curative intent. Postoperative complications occurred in 18 patients, but no mortality occurred. The median disease free interval after curative CWR was 3.3 years; the projected 5-year disease free survival rate was 35%. A disease free interval of more than 2 years after primary treatment predisposed patients to significantly longer tumor free survival after CWR, compared with an interval shorter than 2 years (P = 0.0001). New local recurrence after curative CWR occurred in 6 patients (20%), and distant metastases occurred in 17. Median overall survival was 4.8 years; the projected 5-year survival rate was 45%. After curative resection, these figures were 8.9 years and 58%, respectively, whereas palliative resection resulted in a median survival of 2.3 years and a projected 5-year survival of 21% (P = 0.008). Age > or =35 years at the time of the first diagnosis of breast carcinoma predisposed patients to significantly better survival than age <35 years (P = 0.02). CONCLUSIONS: CWR can provide local control, good palliation, and an acceptable prognosis for patients with recurrence of breast carcinoma. Outcome mainly depends on the completeness of the resection.