Loss of the epithelial marker CDX1 predicts poor prognosis in early-stage CRC patients

BACKGROUND

We have previously shown that non-curative chemotherapy imposes fetal conversion and high metastatic capacity to cancer cells. From the set of genes differentially expressed in Chemotherapy Resistant Cells, we obtained a characteristic fetal intestinal cell signature that is present in a group of untreated tumors and is sufficient to predict patient prognosis. A feature of this fetal signature is the loss of CDX1.

METHODS

We have analyzed transcriptomic data in public datasets and performed immunohistochemistry analysis of paraffin embedded tumor samples from two cohorts of colorectal cancer patients.

RESULTS

We demonstrated that low levels of CDX1 are sufficient to identify patients with poorest outcome at the early tumor stages II and III. Presence tumor areas that are negative for CDX1 staining in stage I cancers is associated with tumor relapse.

CONCLUSIONS

Our results reveal the actual possibility of incorporating CDX1 immunostaining as a valuable biomarker for CRC patients.

Liquid Biopsy Detects Early Molecular Response and Predicts Benefit to First-Line Chemotherapy plus Cetuximab in Metastatic Colorectal Cancer: PLATFORM-B Study

PURPOSE

Chemotherapy plus anti-EGFR is standard first-line therapy in RAS wild-type (wt) metastatic colorectal cancer (mCRC), but biomarkers of early response are clinically needed. We aimed to define the utility of ctDNA to assess early response in patients with mCRC receiving first-line anti-EGFR therapy.

EXPERIMENTAL DESIGN

Prospective multicentric study of tissue patients with RAS wt mCRC treated with first-line chemotherapy plus cetuximab undergoing sequential liquid biopsies. Baseline and early (C3) ctDNA were analyzed by NGS. Trunk mutations were assessed as surrogate marker of total tumor burden. RAS/BRAF/MEK/EGFR-ECD were considered mutations of resistance. ctDNA results were correlated with clinical outcome.

RESULTS

One hundred patients were included. ctDNA was detected in 72% of patients at baseline and 34% at C3. Decrease in ctDNA trunk mutations correlated with progression-free survival (PFS; HR, 0.23; P = 0.001). RAS/BRAF were the only resistant mutations detected at C3. An increase in the relative fraction of RAS/BRAF at C3 was followed by an expansion of the RAS clone until PD, and was associated with shorter PFS (HR, 10.5; P < 0.001). The best predictor of response was the combined analysis of trunk and resistant mutations at C3. Accordingly, patients with "early molecular response" (decrease in trunk and decrease in resistant mutations) had better response (77.5% vs. 25%, P = 0.008) and longer PFS (HR, 0.18; P < 0.001) compared with patients with "early molecular progression" (increase in trunk and/or increase in resistant mutations).

CONCLUSIONS

ctDNA detects early molecular response and predicts benefit to chemotherapy plus cetuximab. A comprehensive NGS-based approach is recommended to integrate information on total disease burden and resistant mutations. See related commentary by Eluri et al., p. 302.

Pazopanib as Second-line Antiangiogenic Treatment in Metastatic Renal Cell Carcinoma After Tyrosine Kinase Inhibitor (TKI) Failure: A Phase 2 Trial Exploring Immune-related Biomarkers for Testing in the Post-immunotherapy/TKI Era

Pazopanib is an oral angiogenesis tyrosine kinase inhibitor (TKI) recommended in metastatic renal cell carcinoma (mRCC) for treatment-naïve patients or those experiencing cytokine failure. We conducted a phase 2, open-label, single-arm study in ten Spanish centres among mRCC patients whose disease progressed on first-line TKI. Patients received pazopanib until disease progression, death, or unacceptable toxicity. Twenty-seven patients were included (median age 62yr, 51.9% male). The objective overall response rate was 14.8% (95% confidence interval [CI] 1.4-28.2%). Median progression-free survival was 6.7mo (95% CI 3.7-11.2) and median overall survival was 20.6mo (95% CI 12.6-27.4). Lower circulating levels of IL-10 (p=0.002) were observed in responding patients at 8 wk after treatment. The median pazopanib treatment duration was 6.0mo (range 1.0-47.0). Most patients (48.1%) had mild or moderate adverse events (AEs), while 44.4% had severe AEs. Pazopanib was clinically active and well tolerated as a second-line treatment in mRCC patients after TKI failure, and circulating IL-10 levels could predict response. PATIENT SUMMARY: Pazopanib could be used as a second-line therapy for the treatment of metastatic renal cell carcinoma after failure of tyrosine kinase inhibitor (TKI) therapy when drugs such as nivolumab and cabozantinib are not available. Now that immunotherapy plus antiangiogenic therapy is a first-line option, IL-10 levels deserve further exploration as a potential predictor of response to sequential TKI-TKI therapy.

The Use of HPV16-E5, EGFR, and pEGFR as Prognostic Biomarkers for Oropharyngeal Cancer Patients

Background: Anti-epidermal-growth-factor-receptor (EGFR) therapies in combination with radiotherapy are being studied on de-escalation clinical trials for HPV-related oropharyngeal cancer (OPC) patients. The HPV16-E5 oncoprotein increases recycling of activated EGFR to the cell surface, enhancing factor signal transduction. Our aim was to evaluate viral HPV16-E5 oncogene expression as well as EGFR and phosphorylated-EGFR (pEGFR), protein levels as biomarkers for clinical outcome in a retrospective cohort of OPC patients.

Methods: Formalin-fixed-paraffin-embedded OPCs were collected from 1990 to 2013. OPC samples containing HPV-DNA were subject to viral E6^*I mRNA detection and p16^INK4a immunohistochemistry (IHC). HPV16-positive cases were evaluated for HPV16-E5 (RT-PCR) and EGFR/pEGFR (IHC). A stratified and matched random sample of HPV-negative samples was used as control and evaluated for EGFR/pEGFR. Overall survival (OS) and disease free survival (DFS) estimates were assessed for locally advanced OPC patients (stage III, IVa,b 7th edition).

Results: Among 788 OPC patient samples, 53 were double positive for HPV16-DNA/p16^INK4a. HPV16-E5 expression was found in 41 of 53 samples (77.4%). EGFR expression was observed in 37.7 vs 70.8% of HPV16-positive vs HPV-negative samples, respectively; (adjusted OR = 0.15) 5% CI = 0.04–0.56]). Expression of pEGFR followed an inverse pattern with 39.6 and 24.9% detection in HPV16-positive and HPV-negative samples; (adjusted OR = 1.58 [95% CI = 0.48–5.17]). Within HPV16-positive cases, no association between HPV16-E5/EGFR nor pEGFR was observed. With a median follow-up of 39.36 months (min = 0.03 – max = 272.07), the combination of HPV status and EGFR or pEGFR expression were predictors of better OS (p < 0.001, for both) and DFS (p < 0.001 for EGFR and p = 0.003 for pEGFR).

Conclusions: HPV16-E5 is highly expressed on HPV16-positive OPCs. Interestingly, HPV16-positive cases expressed significantly more pEGFR while HPV-negative cases expressed more EGFR. The combinations of HPV status and EGFR or pEGFR may be useful biomarkers for evaluating prognosis outcome in OPC patients.

Pazopanib: Evidence review and clinical practice in the management of advanced renal cell carcinoma

Background

Pazopanib is indicated in the first-line treatment of metastatic renal cell cancer (mRCC). The aim of this study was to review the efficacy, safety, and pharmacokinetics of pazopanib and see how these aspects are linked to clinical practice.

Methods

A non-exhaustive systematic review was conducted according to the three topics. No publication restrictions were imposed and the selected languages were Spanish and English. After that, a summary of the main results and findings of the review was presented and discussed during three meetings (one for each topic) with 13 medical oncologists that usually treat mRCC. At these meetings, a questionnaire on the first-line use of pazopanib in clinical practice was also drawn up. After the meetings, the questionnaire was completed by 60 specialist medical oncologists in renal cancer.

Results

The efficacy and safety of pazopanib have been demonstrated in several clinical trials, and subsequently confirmed in studies in real-world clinical practice. In addition to its clinical benefit and good safety profile, quality of life results for pazopanib, which compare favorably to sunitinib, make it a good option in the first-line treatment of patients. Special populations have been included in studies conducted with pazopanib, and it is safe for use in elderly patients, poor functional status, kidney failure, and mild or moderate hepatic impairment, and in patients with concomitant cardiovascular disease. The results of the questionnaire have shown that pazopanib is perceived as an effective drug, in which quality of life (QoL) outcomes are valued above all.

Conclusions

This paper offers a comprehensive and critical summary of efficacy, tolerability, and pharmacokinetics of pazopanib in the treatment of mRCC. Pazopanib is an effective treatment with an acceptable safety profile. Its QoL and tolerability results offer certain advantages when compared with other therapeutic alternatives, and its use appears to be safe in different patient profiles.

Prostacyclin and Thromboxane Production by Autogenous Femoral Veins Grafted into the Arterial Circulation of the Dog

Vascular prostacyclin (PGI2) production is different in the arteries and veins of the dog. Experiments were performed to determine whether chronic grafting of the femoral vein into the arterial circulation would alter the normal PGI2 and thromboxane (TxA2) synthesis of the “arterialized” veins. Spontaneous and arachidonic acid (AA) stimulated PGI2 and TxA2 production (measured by radioimmunoassay of 6-keto PGF1α and TxB2 respectively) were analysed in full thickness punch biopsies of the middle part of the grafts after 3 and 16 months and compared with unoperated veins and arteries. PGI2 production was significantly higher in arteries than in veins but no significant difference in TxB2 production was found. Middle “arterialized” venous graft produced significantly lower amounts of PGI2 and higher amounts of TxB2 than unoperated vessels. PGI2 production was more reduced in the distal than in the middle or the proximal parts of the venous grafts especially when stimulated with AA. These findings do not support the concept that the venous graft was biochemically adapted or “arterialized” in terms of PGI2 production when implanted for 3 months or longer. Rather the markedly decreased PGI2/TxB2 ratio in the middle of the graft may be a contributory cause of thrombogenicity and may be implicated in the pathogenesis of neointimal hyperplasia.

HPV-relatedness definitions for classifying HPV-related oropharyngeal cancer patient do impact on TNM classification and patients' survival

Background

Given the different nature and better outcomes of oropharyngeal carcinoma (OPC) associated with human papillomavirus (HPV) infection, a novel clinical stage classification for HPV-related OPC has been accepted for the 8^th edition AJCC TNM (ICON-S model). However, it is still unclear the HPV-relatedness definition with best diagnostic accuracy and prognostic value.

Material and methods

The aim of this study was to compare different staging system models proposed for HPV-related OPC patients: 7^th edition AJCC TNM, RPA stage with non-anatomic factors (Princess Margaret), RPA with N categories for nasopharyngeal cancer (MD-Anderson) and AHR-new (ICON-S), according to different HPV-relatedness definitions: HPV-DNA detection plus an additional positive marker (p16^INK4a or HPV-mRNA), p16^INK4a positivity alone or the combination of HPV-DNA/p16^INK4a positivity as diagnostic tests.

Results

A total of 788 consecutive OPC cases diagnosed from 1991 to 2013 were considered eligible for the analysis. Of these samples, 66 (8.4%) were positive for HPV-DNA and (p16^INK4a or HPV-mRNA), 83 (10.5%) were p16^INK4a positive and 58 (7.4%) were double positive for HPV-DNA/p16^INK4a. ICON-S model was the staging system, which performed better in our series when using at least two biomarkers to define HPV-causality. When the same analysis was performed considering only p16^INK4a-positivity, RPA stage with non-anatomic factors (Princess Margaret) has the best classification based on AIC criteria.

Conclusion

HPV-relatedness definition for classifying HPV-related OPC patient do impact on TNM classification and patients’ survival. Further studies assessing HPV-relatedness definitions are warranted to better classify HPV-related OPC patients in the era of de-escalation clinical trials.

Plasma ctDNA RAS mutation analysis for the diagnosis and treatment monitoring of metastatic colorectal cancer patients

Background

RAS assessment is mandatory for therapy decision in metastatic colorectal cancer (mCRC) patients. This determination is based on tumor tissue, however, genotyping of circulating tumor (ct)DNA offers clear advantages as a minimally invasive method that represents tumor heterogeneity. Our study aims to evaluate the use of ctDNA as an alternative for determining baseline RAS status and subsequent monitoring of RAS mutations during therapy as a component of routine clinical practice.

Patients and methods

RAS mutational status in plasma was evaluated in mCRC patients by OncoBEAM™ RAS CRC assay. Concordance of results in plasma and tissue was retrospectively evaluated. RAS mutations were also prospectively monitored in longitudinal plasma samples from selected patients.

Results

Analysis of RAS in tissue and plasma samples from 115 mCRC patients showed a 93% overall agreement. Plasma/tissue RAS discrepancies were mainly explained by spatial and temporal tumor heterogeneity. Analysis of clinico-pathological features showed that the site of metastasis (i.e. peritoneal, lung), the histology of the tumor (i.e. mucinous) and administration of treatment previous to blood collection negatively impacted the detection of RAS in ctDNA. In patients with baseline mutant RAS tumors treated with chemotherapy/antiangiogenic, longitudinal analysis of RAS ctDNA mirrored response to treatment, being an early predictor of response. In patients RAS wt, longitudinal monitoring of RAS ctDNA revealed that OncoBEAM was useful to detect emergence of RAS mutations during anti-EGFR treatment.

Conclusion

The high overall agreement in RAS mutational assessment between plasma and tissue supports blood-based testing with OncoBEAM™ as a viable alternative for genotyping RAS of mCRC patients in routine clinical practice. Our study describes practical clinico-pathological specifications to optimize RAS ctDNA determination. Moreover, OncoBEAM™ is useful to monitor RAS in patients undergoing systemic therapy to detect resistance and evaluate the efficacy of particular treatments.

A phase IIb trial of docetaxel concurrent with radiotherapy plus hormotherapy versus radio hormonotherapy in high-risk localized prostate cancer (QRT SOGUG trial): Preliminary report for design, tolerance, and toxicity

15

Background: Docetaxel improves survival in patients (pts) with metastatic hormonosensitive prostate cancer (PC) and castration-resistant prostate cancer. The objective of this phase IIb trial was to assess the activity of low dose docetaxel concurrent with radiotherapy plus standard hormonal treatment in pts with high risk localized CaP. Methods: High-risk localized CaP was defined by ≥ 1 of the following criteria: T3-T4, Gleason score (GS) ≥ 8, PSA > 20 ng/mL, pN+. Pts were randomly assigned to either arm A (LH-RH analogs every 3 months for 3 years and radiotherapy 73.8 Gy [1.8 Gy x 41 fractions] or 74 Gy [2Gy x 37 fractions]) or arm B (LH-RH analogs every 3 months for 3 years, radiotherapy and concurrent weekly docetaxel at 20 mg/m2 for 9 weeks). Chemotherapy was started one week before of radiotherapy. Primary endpoint was PSA relapse according to the Phoenix definition. The planned number of pts was 130 to detect a 15% difference with a power of 80% and an alpha of 0.05 (two-sided). Results: From 12/2008 to 9/2012, 130 pts were accrued (Arm A: 64, Arm B: 66). Median age was 68 years (61-73). Patients had T3-T4 (82.6%), GS ≥ 8 (76.3%), PSA > 20 ng/mL (26.9%) and pN+ (18.9%). All characteristics were well-balanced between arms. Median dose of radiotherapy was 74 Gy (72–74.8) in arm A, and 73.8 Gy ( 72-75.6) in arm B. 75.7% of pts received the planned 9 treatments of docetaxel and median number of cycles delivered per patient was 9. After a median follow-up of 29.6 months (9.6-40.2), most common grade 1/2 toxicities (arm A and arm B) were: cystitis ( 12.5% vs 8.3%), diarrhea (35.9% vs 70%), proctitis (12.5% vs 13.3%), rectal tenesmus (3.1% vs 23.3%), asthenia (23.4% vs 61.6%) and dysuria ( 28.1% vs 30.0%). Toxicity G3/G4 diarrhea was reported in 8.3% of pts in arm B and 0% in arm A. G3/G4 lymphopenia occurred less often in arm A than in arm B (3.1% vs 23.3%). %). There was no toxicity-related death. Conclusions: The QRT SOGUG phase IIb trial met its accrual target and shows that concurrent weekly docetaxel can be administered with standard doses of radiotherapy and without increasing toxicity profile. Clinical trial information: 2008-003554-14.

Cost-effectiveness analysis of pazopanib in second-line treatment of advanced soft tissue sarcoma in Spain

PURPOSE

To assess the efficiency of pazopanib compared with trabectedin in the treatment of adult patients with selective subtypes of advanced soft-tissue sarcoma (STS) after chemotherapy failure.

METHODS

The progression of STS was modeled using a partitioned survival analysis model. Survival curves for pazopanib and trabectedin were modeled using data from PALETTE phase III clinical trial and based on unadjusted indirect comparison. Effectiveness was measured in quality-adjusted life years (QALY). The Spanish National Health System perspective was considered over a 10-year time horizon, including direct health care costs (<euro>, 2014). A discount rate of 3% was applied to both costs and outcomes. The robustness of the results was evaluated using univariate and probabilistic sensitivity analyses (PSA).

RESULTS

Pazopanib was associated with better health outcomes than trabectedin (0.705 versus 0.686 QALY). Pazopanib also showed lower direct health care costs (<euro>21,861 versus <euro>45,338), mainly due to lower cost of pharmacological treatment (<euro>13,762 versus <euro>33,392), administration (<euro>57 versus <euro>2,955) and AE management (<euro>658 versus <euro>1,695) costs. PSA confirmed that pazopanib was a dominant option in 71% of the simulations performed.

CONCLUSIONS

In this analysis, and from a health economics perspective, pazopanib was the option of choice versus trabectedin in the treatment of adult patients with advanced soft-tissue sarcoma after chemotherapy failure.

Phase II study of dovitinib in first line metastatic or (nonresectable primary) adrenocortical carcinoma (ACC): SOGUG study 2011-03

4587

Background: Dovitinib is a novel targeted therapy that inhibits the fribroblast growth factor receptor (FGFR). Preclinical studies have pointed to a major role of this pathway in adrenocortical carcinoma (ACC) thus we aimed to test its clinical efficacy in this tumor. Methods: A phase II proof of concept trial was designed. Since this is an extremely infrequent disease sample size calculation was done taking as a basis the first stage of a two-stage Gehan model. Thus 15 patients needed to be included to show a treatment efficacy of at least 15% (probability of Type I error α = 0.05, power [1 – β] = 0.8). Main inclusion criteria was advanced non-resectable ACC, histologically confirmed, with no prior therapy other than mitotane. Primary endpoint was response rate (RR) by RECIST 1.1 assessed by an independent radiologist. Secondary endpoints included clinical benefit (RR plus stable disease), progression free (PFS) and overall survival (OS). Dovitinib was administered at 500mg daily dose 5 days on 2 days off for 6 months. Continuation of therapy was permitted at physician criteria. Results: From January 2012 to August 2012, 17 patients (5 male and 12 female) have been included in 7 institutions. Median age was 53 years (range 26-72); ECOG was 0-1 in 15 patients, 2 in one patient and N/A in one patient. 77 cycles, defined as one month on treatment, have been administered with dose reductions in 6 (7.8%). Grade 3-4 adverse events deemed as related to the drug were: rash (6%), asthenia (12%), diarrhea (6%), GGT elevation (18%), nausea (6%), hypertriglyceridemia (6%), hypertension (6%), hyperkalemia (6%). 13 patients withdrew treatment because of disease progression and 4 remain on dovitinib. No toxic death was reported. After a median follow-up of 5, 2 months (range 2,27 – 9,7) no objective response has been observed. Median PFS was 1,8 months (CI 95% [ 1,35 -2,25]), median OS has not been reached and clinical benefit has been achieved in 35% of patients with long lasting stable disease (>6 months) in 23%. Conclusions: Though no objective response was observed, a significant number of long lasting stabilizations have been achieved with an acceptable toxicity. These encouraging results merit further study. Clinical trial information: NCT01514526.

PI3KCA mutations in advanced urothelial carcinoma: A potential therapeutic target?

4582

Background: PI3KCA is frequently mutated in human cancer; however, information is scarce regarding its relevance in urothelial carcinoma (UC). We determined the prevalence of mutation and impact on clinical outcome of PI3KCA uniformly-treated patients with metastatic UC. Impact of PI3K and dual PI3K/mTOR inhibition was tested in vitro in UC cell lines with either H1047R or E545K mutation. Methods: 141 samples from invasive UC were scanned for mutations. Of those, complete clinical data was available from 85 cases treated with platinum-based combination chemotherapy for advanced or metastatic disease. DNA was extracted from FFPE material. Mutation status was determined by iPLEX sequencing and confirmed with hME sequencing. Overall survival (OS) was measured from beginning of treatment for metastatic disease to time of death or censored on the last known alive date. Cox proportional hazard model was used to assess the associations of PI3K mutational status and OS. Growth inhibitory effects of a specific PI3K inhibitor and a dual PI3K/mTOR inhibitor (both from Selleck) on UC cell lines with or without mutations were tested using MTT assays. Results: Mutations in the PI3KCA gene were observed in 14 (10%; 95% CI 6-16%) specimens. E545K was detected in all 14 specimens, though one specimen contained mutation at both E545K and H1047R. Among patients with clinical data, there was no statistically significant association between PI3KCA mutational status and OS (HR for having PI3KCA=0.49, 95% CI [0.15, 1.57], p-value 0.22). Preliminary in vitro experiments showed that cell growth was more potently inhibited with dual PI3K/mTOR inhibitors than with PI3K inhibitors. Conclusions: Mutations in the PI3KCA gene were detected in 10% of invasive UC and did not correlate with OS in patients with metastatic UC treated with platinum-based chemotherapy. PI3K inhibition in vitro impacts UC cell growth, though dual PI3K/mTOR inhibitors may have more significant effects than PI3K inhibition alone.

Phase II study of dovitinib in first-line metastatic or nonresectable primary adrenocortical carcinoma (ACC): SOGUG study 2011-03

TPS4688

Background: Dovitinib is a novel targeted therapy, that has proven to inhibit, among other tyrosin kinases, the fibroblast growth factor receptor (FGFR). Since this pathway has been proposed to play a major role in ACC, we aim to test the clinical efficacy of dovitinib in this tumor. Methods: An open label phase II trial has been designed in patients with advanced non-resectable ACC. The objective will be to obtain at least a 15% response rate according to RECIST criteria. Taking as a basis the two-stage Gehan model, 15 patients would need to be included in the first stage to demonstrate a treatment efficacy of at least 15%. Sample size calculation was done based on the following parameters, probability of Type I error α = 0.05, power of the test (1 - β) = 0.8. Main inclusion criteria are advanced non-resectable disease and no prior therapy (other than mitotane). Dovitinib scheduled dose matches currently employed standard in the drug development (500mg daily for 5 days then 2 days off) for 6 months. If clinical benefit is obtained longer treatment will be allowed for particular patients. Since this is an extremely unfrequent disease 7 institutions, members of the SOGUG (Spanish Oncology Genitourinary Group), will participate. The active support of a big collaborative group will guarantee candidate patients to be refereed to such institutions. Starting January 26th 2012 recruitment is scheduled to last around 12 months. A translational research, including whole exome analysis, will be performed in order to improve our scarce knowledge of ACC.

New agents for bladder cancer

Muscle-invasive bladder cancer is an aggressive disease with at least 50% of patients dying from metastases within 2 years of diagnosis. The 5-year survival rate for metastatic bladder cancer is <15%. Although modern combination chemotherapy regimens have improved median survival from 6 to 14 months compared with best supportive care, there is still a great opportunity for improvement. New therapies and strategies for better patient and treatment selection are now being investigated for advanced bladder cancer. These include agents that target several pathways involved in the pathogenesis of the disease--such as growth factor receptors, angiogenic pathways, p53, cell cycle checkpoints and apoptosis--as well as novel chemotherapeutic agents. Results from recent and ongoing trials suggest that some of these agents could soon emerge as useful players to overcome the limitations of our present therapies.

Gemcitabine/cisplatin in patients with advanced bladder and impaired renal function: A retrospective analysis

274

Background: A four-weekly regimen of gemcitabine and cisplatin (GEMCIS) has similar activity and is less toxic than MVAC in advanced bladder cancer. However, full-dose cisplatin in unfit patients with impaired renal function is contraindicated and other carboplatin-based schedules have been developed. We have previously reported the feasibility of GEMCIS in a biweekly schedule in unfit patients with renal impairment. Here we report a multicenter retrospective study of this biweekly regimen in patients with impaired renal function.

Methods: Between January 2004 and October 2009, 40 patients with locally advanced nonsurgically resectable or metastatic bladder cancer and impaired renal function were included. Treatment consisted of gemcitabine 2500 mg/m2 on day 1 and cisplatin 35 mg/m2 on day 1, every 14 days.

Results: Median age of the patients was 73 years (range: 51-82 years). Median IK was 80% (range: 60-100%). Mean creatinine clearance was 49 ml/min (range:37-59 ml/min). Eight patients had previously received chemotherapy with gemcitabine and/or platinum based therapy. Metastatic localizations were: 17 lymph nodes, 10 pulmonary, 10 bone, 7 liver, 12 pelvic and 1 central nervous system. The median number of cycles/patient was 6 (1-13). Out of 36 patients evaluable for response, there was one complete response, 14 partial responses (ORR: 42%; 95% CI 27-58%), 11 stabilizations and 10 progressive diseases. Hematologic toxicities were grade 1 anaemia in 15 patients, grade 2 in 8; grade 3 in 2; grade 3 neutropenia in 5 patients and grade 4 in 1 patient; grade 3 plaquetopenia in 3 patients. Nonhematologic toxicities were grade 1-2 vomiting in 2 patients. Two patients showed a grade 2 hepatic toxicity. Worsening of the renal function was observed in two patients. Alopecia grade 1-2 was seen in three patients. There was one toxic death related to metabolic acidosis.The median progression-free survival is 15 weeks. The median OS from first cycle of GEMCIS is 35 weeks and 1-year OS is 43% (St error 9%).

Conclusions: A two-weekly schedule of gemcitabine plus cisplatin is feasible, active, and generally well tolerated in an outpatient setting in unfit patients with poor renal reserve.

No significant financial relationships to disclose.

Stable and sensitive flow-through monitoring of phenol using a carbon nanotube based screen printed biosensor

A stable and sensitive biosensor for phenol detection based on a screen printed electrode modified with tyrosinase, multiwall carbon nanotubes and glutaraldehyde is designed and applied in a flow injection analytical system. The proposed carbon nanotube matrix is easy to prepare and ensures a very good entrapment environment for the enzyme, being simpler and cheaper than other reported strategies. In addition, the proposed matrix allows for a very fast operation of the enzyme, that leads to a response time of 15 s. Several parameters such as the working potential, pH of the measuring solution, biosensor response time, detection limit, linear range of response and sensitivity are studied. The obtained detection limit for phenol was 0.14 x 10(-6) M. The biosensor keeps its activity during continuous FIA measurements at room temperature, showing a stable response (RSD 5%) within a two week working period at room temperature. The developed biosensor is being applied for phenol detection in seawater samples and seems to be a promising alternative for automatic control of seawater contamination. The developed detection system can be extended to other enzyme biosensors with interest for several other applications.

Excision repair cross-complementing 1 (ERCC1) and survival in advanced bladder cancer: Confirmatory results using immunohistochemistry

5025

Background: DNA damaging agents are the backbone of combination chemotherapy regimens for the treatment of advanced bladder cancer. We hypothesized that levels of DNA repair genes such as ERCC1 could predict survival in patients receiving platinum based therapy. Our previous work (Bellmunt J et al, Ann Oncol. 2007) showed that survival was significantly higher in advanced bladder cancer patients with low gene expression levels of ERCC1 measured by RT-qPCR (25.4 versus 15.4 months; p = 0.03). We aimed to confirm these findings using immunohistochemistry (IHC) in an independent cohort of advanced bladder cancer patients treated with cisplatin-based chemotherapy at our institution. Methods: Formalin-fixed paraffin-embedded tumor tissue was available from 51 patients. IHC stains for ERCC1 protein levels were scored as percentage and intensity of positive cells. ERCC1 staining was considered positive if detected in ≥1% tumor cells. The Kaplan-Meier method was used to calculate survival and the Cox proportional hazards model was used to examine the prognostic value of protein expression levels. Results: ERCC1 staining was negative in 60% of patients, weakly positive (1–10% positive cells) in 21% and strongly positive (>10% positive cells) in 19%. Median overall survival for all patients was 14.4m (95% CI 6.7–16.1m). Median disease-specific survival was significantly higher in patients negative for ERCC1 by IHC (12.6m versus 8.6m; p = 0.032). Conclusions: Our results using the more simple IHC technique confirm the prognostic value of ERCC1 expression in advanced bladder cancer. Patients with high expression of ERCC1 by IHC have a worse disease-specific survival than patients with no expression. A correlative study of IHC and RT-qPCR in both sets of samples is ongoing.

No significant financial relationships to disclose.

Loss of Phosphatase and Tensin homologue deleted on chromosome 10 engages ErbB3 and insulin-like growth factor-I receptor signaling to promote antiestrogen resistance in breast cancer

Knockdown of the tumor suppressor phosphatase Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) with shRNA in three estrogen receptor (ER)-positive breast cancer cell lines resulted in increased phosphatidylinositol-3 kinase (PI3K) and AKT activities, resistance to tamoxifen and fulvestrant, and hormone-independent growth. PTEN knockdown induced the up-regulation of ER transcriptional activity in MCF-7 cells but decreased ER protein levels and transcriptional activity in T47D and MDA-361 cells. Tamoxifen and fulvestrant treatment inhibited estradiol-induced ER transcriptional activity in all shPTEN cell lines but did not abrogate the increased cell proliferation induced by PTEN knockdown. PTEN knockdown increased basal and ligand-induced activation of the insulin-like growth factor-I (IGF-I) and ErbB3 receptor tyrosine kinases, and prolonged the association of the p85 PI3K subunit with the IGF-I receptor (IGF-IR) effector insulin receptor substrate-1 and with ErbB3, implicating PTEN in the modulation of signaling upstream of PI3K. Consistent with these data, PTEN levels inversely correlated with levels of tyrosine-phosphorylated IGF-IR in tissue lysate arrays of primary breast cancers. Inhibition of IGF-IR and/or ErbB2-mediated activation of ErbB3 with tyrosine kinase inhibitors restored hormone dependence and the growth inhibitory effect of tamoxifen and fulvestrant on shPTEN cells, suggesting that cotargeting both ER and receptor tyrosine kinase pathways holds promise for the treatment of patients with ER+, PTEN-deficient breast cancers.

Loss of PTEN engages ErbB3 and IGF-I receptor signaling to promote antiestrogen resistance in breast cancer

Abstract #73

We sought to determine whether loss of the lipid phosphatase PTEN confers resistance to antiestrogens in estrogen receptor (ER)-positive breast cancer cells and primary tumors. Stable knockdown of PTEN expression (PTEN-kd) with shRNA in MCF-7, T47D, and MDA-361 ER+ human breast cancer cells resulted in upregulation of PI3K and P-Akt, resistance to tamoxifen and faslodex, and estrogen-independent growth. Upon PTEN-kd, ER levels were maintained in MCF-7 cells but markedly reduced in T47D and MDA-361 cells. While PTEN-kd upregulated ER transcriptional reporter activity in MCF-7 cells, opposite effects were seen in T47D and MDA-361 cells.&#x2028; We evaluated mechanisms of PI3K activation in PTEN-kd cells by immunoprecipitating the p85 regulatory subunit of PI3K and examining p85-bound tyrosine-phosphorylated adaptors or receptors. PTEN-kd increased the binding of p85 to IRS-1 (MCF-7) and ErbB3 (T47D). PTEN-kd increased PI3K pathway sensitivity to IGF-I (MCF-7) and endogenous ligand (T47D, MDA-361). PTEN-kd cells had increased and prolonged activation of IGF-IR and ErbB3, thus implicating PTEN in the regulation of signaling upstream of PI3K. Further, PTEN-kd increased non-genomic, estrogen-induced signaling via IGF-IR by increasing p85-IRS-1 binding and activation of PI3K/Akt in MCF-7 cells. Inhibition of PI3K and mTOR with the small molecule BEZ235, of IGF-IR with the small molecule AEW541, and/or of ErbB2-mediated activation of ErbB3 with lapatinib restored the growth inhibitory effect of antiestrogens.&#x2028; We generated gene expression signatures of PTEN loss in each cell line by microarray analyses. Comparison of these signatures to the Connectivity Map (Science 313:1929, 2006) suggested activation of PI3K, as signatures of PTEN loss negatively connected with those induced by the PI3K inhibitors wortmannin and LY294002 (all p&lt;0.06). We found a 24-gene signature of PTEN loss common to all 3 lines, which we used to score the gene expression profiles of tumors from a cohort of 268 patients with ER+ breast cancer treated with adjuvant tamoxifen for 5 yrs and a median follow-up of 9.1 years (BMC Genomics 9:239, 2008). Patients with tumors exhibiting a signature of PTEN loss had shorter relapse-free survival (p&lt;0.0001; log rank test). Eleven genes in the PTEN signature were individually predictive of disease outcome (p&lt;0.05). In a separate, smaller cohort of patients with ER+ cancers treated with adjuvant tamoxifen (n=34), undetectable PTEN in tumor cells (measured by IHC) correlated with shorter relapse-free survival vs. tumors with detectable PTEN (p=0.06). These data suggest that 1) PTEN loss confers antiestrogen resistance to ER+ breast cancer by genomic and non-genomic mechanisms; 2) PTEN loss is permissive for activation of IGF-IR and ErbB3 signaling; 3) inhibition of IGF-IR and/or ErbB signaling pathways overcomes the resistance to antiestrogens conferred by PTEN loss; and 4) a gene expression signature reflective of loss of PTEN and/or absence of PTEN protein can predict poor patient outcome after adjuvant hormonal therapy.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 73.

Acquired resistance to EGFR tyrosine kinase inhibitors in cancer cells is mediated by loss of IGF-binding proteins

Although some cancers are initially sensitive to EGFR tyrosine kinase inhibitors (TKIs), resistance invariably develops. We investigated mechanisms of acquired resistance to the EGFR TKI gefitinib by generating gefitinib-resistant (GR) A431 squamous cancer cells. In GR cells, gefitinib reduced phosphorylation of EGFR, ErbB-3, and Erk but not Akt. These cells also showed hyperphosphorylation of the IGFI receptor (IGFIR) and constitutive association of IRS-1 with PI3K. Inhibition of IGFIR signaling disrupted the association of IRS-1 with PI3K and restored the ability of gefitinib to downregulate PI3K/Akt signaling and to inhibit GR cell growth. Gene expression analyses revealed that GR cells exhibited markedly reduced IGF-binding protein 3 (IGFBP-3) and IGFBP-4 RNA. Addition of recombinant IGFBP-3 restored the ability of gefitinib to downregulate PI3K/Akt signaling and to inhibit cell growth. Finally, gefitinib treatment of mice with A431 xenografts in combination with an IGFIR-specific monoclonal antibody prevented tumor recurrence, whereas each drug given alone was unable to do so. These data suggest that loss of expression of IGFBPs in tumor cells treated with EGFR TKIs derepresses IGFIR signaling, which in turn mediates resistance to EGFR antagonists. Moreover, combined therapeutic inhibition of EGFR and IGFIR may abrogate this acquired mechanism of drug resistance and is thus worthy of prospective clinical investigation.

Short preoperative treatment with erlotinib inhibits tumor cell proliferation in hormone receptor-positive breast cancers

PURPOSE

To administer the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib to patients with operable untreated breast cancer during the immediate preoperative period and to measure an antiproliferative and/or a proapoptotic effect in the post-therapy specimen and determine a biomarker profile associated with evidence of erlotinib-mediated cellular activity.

PATIENTS AND METHODS

Newly diagnosed patients with stages I to IIIA invasive breast cancer were treated with erlotinib 150 mg/d orally for 6 to 14 days until the day before surgery. Erlotinib plasma levels were measured by tandem mass spectrometry the day of surgery. Drug-induced changes in tumor cell proliferation and apoptosis were assessed by Ki67 immunohistochemistry and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling analysis, respectively, in biopsies from the pretherapy and surgical specimens. Biopsies were also evaluated for P-EGFR, P-HER-2, P-MAPK, P-Akt, P-S6, and S118 P-ER alpha.

RESULTS

In drug-sensitive PC9 xenografts, 5 days of treatment with erlotinib were enough to induce a maximal inhibition of cell proliferation and induction of apoptosis. Forty-one patients completed preoperative treatment with erlotinib. Grade <or= 2 rash and diarrhea were the main toxicities. Erlotinib inhibited tumor cell proliferation (Ki67), P-EGFR, and P-HER-2. The inhibition of proliferation occurred in estrogen receptor (ER) -positive but not in human epidermal growth factor receptor 2 (HER-2) -positive or triple-negative cancers. Treatment was associated with a significant reduction of P-MAPK, P-Akt, P-S6, and S118 P-ER alpha in hormone receptor-positive cancers.

CONCLUSION

A presurgical approach to evaluate cellular responses to new drugs is feasible in breast cancer. EGFR inhibitors are worthy of testing against ER-positive breast cancers but are unlikely to have clinical activity against HER-2-positive or triple-negative breast cancers.

Human breast cancer cells selected for resistance to trastuzumab in vivo overexpress epidermal growth factor receptor and ErbB ligands and remain dependent on the ErbB receptor network

PURPOSE

We have investigated mechanisms of acquired resistance to the HER2 antibody trastuzumab in BT-474 human breast cancer cells.

EXPERIMENTAL DESIGN

BT-474 xenografts established in athymic nude mice were eliminated by trastuzumab. Continuous cell lines (HR for Herceptin resistant) were generated from tumors that recurred in the presence of continuous antibody therapy.

RESULTS

The isolated cells behaved resistant to trastuzumab in culture as well as when reinjected into nude mice. They retained HER2 gene amplification and trastuzumab binding and were exquisitely sensitive to peripheral blood mononuclear cells ex vivo in the presence of the antibody. The HR cells exhibited higher levels of phosphorylated epidermal growth factor receptor (EGFR) and EGFR/HER2 heterodimers. Phosphorylation of HER2 in HR cells was inhibited by the EGFR tyrosine kinase inhibitors erlotinib and gefitinib. Gefitinib also inhibited the basal association of p85 with phosphorylated HER3 in HR cells. Both inhibitors as well as the dual EGFR/HER2 inhibitor, lapatinib, induced apoptosis of the HR cells in culture. Growth of established HR5 xenografts was inhibited by erlotinib in vivo. In addition, the HR cells overexpressed EGFR, transforming growth factor alpha, heparin-binding EGF, and heregulin RNAs compared with the parental trastuzumab-sensitive cells.

CONCLUSIONS

These results are consistent with the inability of trastuzumab to block the heterodimerization of HER2 and suggest that amplification of ligand-induced activation of ErbB receptors is a plausible mechanism of acquired resistance to trastuzumab that should be investigated in primary mammary cancers.

Inhibition of epidermal growth factor receptor signaling elevates 15-hydroxyprostaglandin dehydrogenase in non-small-cell lung cancer

Evidence indicates that the induction of cyclooxygenase-2 (COX-2) and high prostaglandin E2 (PGE2) levels contribute to the pathogenesis of non-small-cell lung cancer (NSCLC). In addition to overproduction by COX-2, PGE2 concentrations also depend upon the levels of the PGE2 catabolic enzyme 15-hydroxyprostaglandin dehydrogenase (15-PGDH). We find a dramatic down-regulation of PGDH protein in NSCLC cell lines and in resected human tumors when compared with matched normal lung. Affymetrix array analysis of 10 normal lung tissue samples and 49 resected lung tumors revealed a much lower expression of PGDH transcripts in all NSCLC histologic groups. In addition, treatment with the epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) erlotinib increased the expression of 15-PGDH in a subset of NSCLC cell lines. This effect may be due in part to an inhibition of the extracellular signal-regulated kinase (ERK) pathway as treatment with mitogen-activated protein kinase kinase (MEK) inhibitor U0126 mimics the erlotinib results. We show by quantitative reverse transcription-PCR that the transcript levels of ZEB1 and Slug transcriptional repressors are dramatically reduced in a responsive cell line upon EGFR and MEK/ERK inhibition. In addition, the Slug protein, but not ZEB1, binds to the PGDH promoter and represses transcription. As these repressors function by recruiting histone deacetylases to promoters, it is likely that PGDH is repressed by an epigenetic mechanism involving histone deacetylation, resulting in increased PGE2 activity in tumors. This effect is reversible in a subset of NSCLC upon treatment with an EGFR TKI.

Inhibition of TGF-beta with neutralizing antibodies prevents radiation-induced acceleration of metastatic cancer progression

We investigated whether TGF-beta induced by anticancer therapies accelerates tumor progression. Using the MMTV/PyVmT transgenic model of metastatic breast cancer, we show that administration of ionizing radiation or doxorubicin caused increased circulating levels of TGF-beta1 as well as increased circulating tumor cells and lung metastases. These effects were abrogated by administration of a neutralizing pan-TGF-beta antibody. Circulating polyomavirus middle T antigen-expressing tumor cells did not grow ex vivo in the presence of the TGF-beta antibody, suggesting autocrine TGF-beta is a survival signal in these cells. Radiation failed to enhance lung metastases in mice bearing tumors that lack the type II TGF-beta receptor, suggesting that the increase in metastases was due, at least in part, to a direct effect of TGF-beta on the cancer cells. These data implicate TGF-beta induced by anticancer therapy as a pro-metastatic signal in tumor cells and provide a rationale for the simultaneous use of these therapies in combination with TGF-beta inhibitors.

Epidermal Growth Factor Receptor (EGFR) Antibody Down-regulates Mutant Receptors and Inhibits Tumors Expressing EGFR Mutations

Activating mutations in the kinase domain of the EGF receptor have been reported in non-small cell lung cancer. The majority of tumors expressing these mutants are sensitive to ATP mimetics that inhibit the EGFR tyrosine kinase. The effect of antibodies that bind to the ectodomain of the receptor is less clear. We report herein the effects and mechanisms of action of the antibody cetuximab in lung cancer cells that naturally express receptor mutations and in ErbB-null 32D hematopoietic cells transfected with mutant EGFR. Treatment with cetuximab down-regulated EGFR levels and inhibited cell growth both in vitro and in vivo. This was associated with inhibition of ligand-independent EGFR signaling. These effects were seen in 32D cells arguing the growth inhibitory action was not because of the blockade of autocrine ligand action. Both antibody-induced EGFR down-regulation and inhibition of growth required receptor dimerization as monovalent Fab fragments only eliminated receptor levels or reduced cell proliferation in the presence of antihuman IgG. Finally, cetuximab inhibited growth of H1975 lung cancer cells and xenografts, which expressed L858R/T790M EGFR and were resistant to EGFR tyrosine kinase inhibitors. These data suggest that cetuximab is an effective therapy against mutant EGFR-expressing cancer cells and thus can be considered in combination with other anti-EGFR molecules.

Phase I Pharmacokinetic and Pharmacodynamic Study of Weekly 1-Hour and 24-Hour Infusion BMS-214662, a Farnesyltransferase Inhibitor, in Patients With Advanced Solid Tumors

Purpose

BMS-214662 is a potent, nonpeptide, small molecule inhibitor of human farnesyltransferase (FT). We have conducted a phase I pharmacokinetic (PK) and pharmacodynamic study of BMS-214662 administered intravenously weekly with 1- and 24-hour infusions. The objectives were to determine the dose-limiting toxicities and the recommended dose (RD), to describe PKs, and to evaluate the relationships between BMS-214662 exposure, FT inhibition, downstream signaling, and induction of apoptosis in tumor samples.

Patients and Methods

Patients with advanced solid tumors and adequate organ function were eligible. The dose was escalated according to a modified Fibonacci schedule.

Results

BMS-214662 was escalated from 56 to 278 mg/m2 in 37 patients in the 1-hour schedule, and from 84 to 492 mg/m2 in 31 patients in the 24-hour schedule. Dose-limiting toxicities included gastrointestinal and renal events. The RDs were 209 mg/m2 and 275 mg/m2 in the 1- and 24-hour schedules, respectively. Five patients (three with breast, one with gastric, and one with renal cell cancer) had clinical benefit from treatment. BMS-214662 exhibited linear PKs with area under the concentration-time curves at the RDs of 27 and 32 μM × h in the 1- and 24-hour schedules, respectively. The pattern of FT inhibition in peripheral-blood mononuclear cells at the RDs was different in the two schedules: high (> 80%) but short-lived (≤ 6 hours) in the 1-hour infusion and moderate (> 40%) but long-lived (24 hours) in the 24-hour infusion. BMS-214662 induced apoptosis in tumors but did not inhibit MAPK signaling.

Conclusion

BMS-214662 can be safely delivered in both the 1-hour and 24-hour infusions at biologically active doses, with the preclinical, PK, and pharmacodynamic profiles favoring the 24-hour schedule.

Early changes in protein expression detected by mass spectrometry predict tumor response to molecular therapeutics

Biomarkers that predict therapeutic response are essential for the development of anticancer therapies. We have used matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to directly analyze protein profiles in mouse mammary tumor virus/HER2 transgenic mouse frozen tumor sections after treatment with the erbB receptor inhibitors OSI-774 and Herceptin. Inhibition of tumor cell proliferation and induction of apoptosis and tumor reduction were predicted by a >80% reduction in thymosin beta4 and ubiquitin levels that were detectable after 16 hours of a single drug dose before any evidence of in situ cellular activity. These effects were time- and dose-dependent, and their spatial distribution in the tumor correlated with that of the small-molecule inhibitor OSI-774. In addition, they predicted for therapeutic synergy of OSI-774 and Herceptin as well as for drug resistance. These results suggest that drug-induced early proteomic changes as measured by MALDI-MS can be used to predict the therapeutic response to established and novel therapies.

[Importance of 5569G/A polymorphism in intron 4 of HFE gene in the diagnosis of hereditary hemochromatosis]

BACKGROUND

The presence of the 5569A polymorphism may lead to misdiagnosis of patients susceptible of hereditary hemochromatosis (HH). For that reason, samples containing the Cys282Tyr mutation were revised and the frequency of this polymorphism in our environment was assessed.

PATIENTS AND METHOD

Twenty samples were retested and 56 controls were included. The study was performed by PCR-RFLP.

RESULTS

The diagnosis was confirmed in 8 cases susceptible of error. However, an amplification deficiency of normal alleles was detected in 2 heterozygous (17%). The allelic frequency of the 5569A polymorphism in the control population was 14.3%.

CONCLUSIONS

Although misdiagnosis was not committed, we recommend changing to any primer that does not include the 5569G/A polymorphism in the study of HH.

Elastofibroma dorsi as a cause of shoulder pain or snapping scapula

Elastofibroma dorsi is a benign soft tissue tumor, not well-known because of its low incidence, located in the chest wall in the subscapular area. In 10 patients with elastofibroma dorsi, the clinical symptoms were snapping scapula or shoulder pain. In three of the patients, the previous diagnosis was shoulder impingement, and the patients were treated without success. The clinical diagnosis was confirmed by magnetic resonance imaging. Surgical treatment resolved the symptoms in all patients. This tumor should be considered in the differential diagnosis of snapping scapula or shoulder impingement.

[Normal values of valvular annular areas. Comparison of the results of a necropsy and an echocardiographic series]

INTRODUCTION AND OBJECTIVES

Measurement of valvular annular area is necessary for valvular flow volumen quantification by Doppler echocardiography. The aim of this work was to compare normal valvular annular area values obtained in a necropsic and an echocardiographic series and to ascertain whether a relationship exists between these areas and several anthropometric variables.

METHODS

Necropsic series: valvular annular area was measured in 20 hearts from deceased patients (age range: 9-79 years; mean 52 +/- 18) without cardiovascular disease. Echocardiographic series: Valvular annular area was determined in 156 patients (age range: 6-86 years; mean 37 +/- 20) without cardiovascular disease.

RESULTS

Necropsic series: multiple regression analysis showed valvular annular area values to be related mainly to height (p < 0.001) but also to weight (p < 0.01). Correlations between valvular annular area and body surface were low (r = 0.64-0.75). Aortic annular area index was slightly lower than the pulmonary annular area index and half that of the mitral annular area index (2.2 +/- 0.4, 2.5 +/- 0.5 and 4.4 +/- 0.8 cm2/m2, respectively). Tricuspid annular area index was the largest (6.7 +/- 1.0 cm2/m2). ECHOCARDIOGRAPHIC SERIES: Multiple regression analysis also showed a relationship between valvular annular area and height (p < 0.00001) and weight (p < 0.004). Correlations between valvular annular real values and body surface were poor (r = 0.45-0.71). Mean values of aortic, pulmonary and mitral valvular annular area indices were similar to those obtained in the necropsic series (2.1 +/- 0.2, 2.1 +/- 0.3, 4.1 +/- 0.6 cm2/m2, respectively). However, the tricuspid annular area index was clearly lower (4.5 +/- 0.6 cm2/m2, p < 0.001).

CONCLUSIONS

Valvular annular area is influenced mainly by height, but also by weight. The correlation between these values and body surface is poor. Aortic annular area is similar to the pulmonary annular area and half that of the mitral annulus. Normal values determined by echocardiography and necropsy are similar, although tricuspid annular area by apical view is smaller than that obtained in the necropsic series.

Fertility and histology after rabbit ovarian wedge resection with CO2 laser or electrocautery using posterior reconstruction with nylon or polyglactin sutures

In an experimental study in rabbits, the CO2 laser and electrocautery were compared in performing microsurgical ovarian wedge resection; polyglactin and nylon sutures were compared for ovarian reconstruction. Histologic reaction, adhesion formation, and functional parameters (number of corpora lutea, number of pregnancies, nidation index) were evaluated 30 and 90 days postoperatively. Thirty days after surgery, the tissue inflammatory response was very similar in the four groups; fibrosis was not detected. Significant reductions (P less than 0.01) were found for the experimental (operated right ovary) vs. the control (unoperated left ovary) groups when comparing the number of corpora lutea and the number of pregnancies. No significant differences in the nidation index were demonstrated. Adhesion formation was not different between any of the experimental procedures; adhesions were not detected in the control ovaries. At 90 days, the polyglactin suture was entirely absorbed and no inflammatory reaction persisted. Minimal giant cell infiltration was found around the nylon suture. The histologic differences between the two sutures were statistically significant (P less than 0.02). No fibrosis was observed. The functional parameters did not reveal statistically significant differences between the two sutures.

[Gastric carcinoma with a lymphoid stroma]

Carcinomas with lymphoid stroma have been described in different locations: breast, uterine cervix, nasopharynx, esophagus and stomach. These neoplasms have a better prognosis probably due to the lymphoid reaction that takes place in the tumoral stroma. For this reason many authors prefer to consider this entity separate from the rest of gastric carcinomas. We present a case of gastric carcinoma with lymphoid stroma and neuroendocrine features. Such association has not been previously described in the Spanish literature.

Hepatoid gastric adenocarcinoma

A case of hepatoid gastric adenocarcinoma is reported. The tumor had the histological and immunohistochemical features of both liver cell carcinoma and conventional intestinal-type adenocarcinoma. We discuss the main clinical and pathological features of this uncommon variety of gastric cancer.

Prostacyclin and thromboxane production by autogenous femoral veins grafted into the arterial circulation of the dog

Vascular prostacyclin (PGI2) production is different in the arteries and veins of the dog. Experiments were performed to determine whether chronic grafting of the femoral vein into the arterial circulation would alter the normal PGI2 and thromboxane (TxA2) synthesis of the "arterialized" veins. Spontaneous and arachidonic acid (AA) stimulated PGI2 and TxA2 production (measured by radioimmunoassay of 6-keto PGF1 alpha and TxB2 respectively) were analysed in full thickness punch biopsies of the middle part of the grafts after 3 and 16 months and compared with unoperated veins and arteries. PGI2 production was significantly higher in arteries than in veins but no significant difference in TxB2 production was found. Middle "arterialized" venous graft produced significantly lower amounts of PGI2 and higher amounts of TxB2 than unoperated vessels. PGI2 production was more reduced in the distal than in the middle or the proximal parts of the venous grafts especially when stimulated with AA. These findings do not support the concept that the venous graft was biochemically adapted or "arterialized" in terms of PGI2 production when implanted for 3 months or longer. Rather, the markedly decreased PGI2/TxB2 ratio in the middle of the graft may be a contributory cause of thrombogenicity and may be implicated in the pathogenesis of neointimal hyperplasia.