Analysis of allelic imbalance in patients with colorectal cancer according to stage and presence of synchronous liver metastases.

OBJECTIVE: To investigate the relationship between number and location of allelic imbalances (AI) and local tumor progression according to Astler-Coller classification. SUMMARY BACKGROUND DATA: Spontaneous errors in DNA replication (i.e., allelic imbalance or microsatellite instability) have been suggested to play an important role in carcinomatous transformation as reflecting alterations of gene function. METHODS: One hundred two consecutive patients with colorectal carcinoma undergoing surgical resection were included in this study. Patients were distributed according to the Astler-Coller classification as stages A (n = 7), B1 (n = 15), B2 (n = 24), C (n = 31), and D (n = 25). Fluorescent polymerase chain reaction was performed on frozen tumor, normal colon mucosa, and blood DNA at 35 microsatellite markers. Allelic imbalance frequency was compared with tumor staging. RESULTS: The percentage of AI was significantly higher in stage D than in A/B1 and B2. In addition, the percentage of AI was significantly higher in 10 synchronous colorectal liver metastases than in stage A/B1 and B2 tumors. However, the allelotyping revealed a subgroup of A/B1 tumors with a high AI frequency. Statistical analysis showed that the presence of AI at microsatellites D1S305, D2S138, D3S1282, D17S790, and D22S928 presented a significantly positive correlation with stages. CONCLUSION: The frequency of AI significantly correlates with tumor progression of colorectal cancer. Primary tumors with synchronous colorectal liver metastases showed a higher percentage of AI, suggesting that a frequency of AI greater than 35% with this selection of markers indicates a high risk of local progression and of development of metastases.

Pancreatic metastasis of alveolar soft-part sarcoma: a case report and review of the literature.

Alveolar soft-part sarcoma is a rare tumour. Patients commonly present with distant metastases both at the time of diagnosis and late in the course of disease. We present a case of pancreatic metastasis, occurring more than six years after diagnosis. Treatment consisted in subtotal pancreatoduodenectomy with pylorus resection. Both specific patterns of relapse and treatment opportunities of this uncommon feature are discussed.

[Wound healing and hyperbaric oxygen. Experimental study of the angiogenesis phase in the rat]. / La cicatrisation sous oxygénothérapie hyperbare. Etude expérimentale de sa phase angiogénique chez le rat.

Hyperbaric oxygen therapy (HBO) is widely reported as highly favourable to wound healing. The experimental models generally used to investigate its effects are difficult to set up and reliable quantification of the results obtained is rarely achieved. The underlying pathophysiological mechanisms occurring during HBO remain poorly understood and its mode of application for clinical practice is difficult to standardise. Our study was carried out to assess the contributions of oxygen and hyperbaric pressure on the initial steps of wound healing. It was based on qualitative and quantitative analysis of the development of the angiogenic process in a granulation tissue bud, using animals implanted with fibrin chambers, an in vivo model initially described by Dvorak in guinea pigs. In our study, rats were further submitted to HBO (OHB group) or hyperbaric air (Air-HB group) treatments. The control group (Control group) consisted of rats maintained in the treatment tank under normal atmospheric conditions. Nine specific parameters were determined and analysed during the course of the angiogenic process by classical histological techniques. The vascular density and the height of the bud were particularly examined at day 7, 14 and 21 following chamber implantation. At D7 the neovessel density and bud height were significantly higher in OHB group than in Air-HB or Control groups, thus confirming the beneficial effects of this treatment on the initial steps of wound healing. Nevertheless, the results reported herein also suggest a possible inhibitory effect of hyperbaric therapy alone on this very early process, although the pathophysiological significance of this effect on wound healing remains to be determined.

[Immunohistochemistry in the differential diagnosis of mesothelioma and adenocarcinoma. Evaluation of 5 new antibodies and 6 traditional antibodies]. / L'immunohistochimie dans le diagnostic différentiel entre mésothéliome et adénocarcinome. Evaluation de 5 nouveaux anticorps et réévaluation de 6 anticorps traditionnels.

The aim of this study was to evaluate three recently marketed putative mesothelioma-binding antibodies, calretinin, HBME-1 and thrombomodulin, and two putative adenocarcinoma-binding antibodies, AUA1 and MOC31, on paraffin sections from 28 mesotheliomas and 30 adenocarcinomas. Moreover, the expression of ACE, BerEP4, CA125, CA19.9, LeuM1 and vimentin was assessed. Calretinin, HBME-1 and thrombomodulin, which showed a 100%, 89% and 43% sensitivity, and a 50%, 70% and 87% specificity for mesothelioma respectively, were less efficient than vimentin (100% specificity and 67% sensitivity) for the positive identification of mesothelioma. AUA1, BerEP4 and MOC31 were 100% sensitive to adenocarcinoma, with BerEP4 and MOC31 having the highest specificity (86% each). The immunophenotype "vimentin-positive, ACE-negative, CA19.9-negative" yielded 100% sensitivity and 97% specificity for diagnosis of mesothelioma. We advocate the use of the four-marker panel of ACE, CA19.9, MOC31 (or BerEP4) and vimentin for differentiating mesothelioma from adenocarcinoma.