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Biomedical subjects

M Canis

Publications and source records attributed to M Canis.

At least 55 records · Page 3Linked to original sources

[Laparoscopy and gynecologic cancer: is it still necessary to debate or only convince the incredulous?].

Many papers suggested that laparoscopic treatment of cancer could be achieved and taught safely. Although cases reports about trocar site metastasis and national survey about inadequate management of early ovarian cancer suggested that laparoscopic management of cancer may be dangerous. The current literature may be summarized as follows. An inadequate surgical management performed by laparoscopy as well as by laparotomy may worsen the prognosis of an early ovarian cancer. If the abdominal wall is protected with a bag and the tumour is not morcellated, the incidence of trocar site site metastasis is about 1%. Animal studies demonstrated that the laparoscopic management of cancer has both advantages and disadvantages. Preliminary results from prospective randomised trials in the treatment of colon cancer suggested that the survival rate is similar after laparoscopy and after laparotomy. The risk of dissemination appears high when a large number of malignant cells are present in patients operated using an increased abdominal pressure and a CO2 pneumoperitoneum. These data suggest that laparoscopic treatment of gynaecologic cancer is not dangerous if an adequate surgical technique is used. However morcellation of suspicious solid tumours, treatment of adnexal tumours with external vegetations but without peritoneal dissemination and of bulky lymph nodes should be considered as contra-indications to CO2 laparoscopy, puncture of an ovarian tumour with intracystic vegetations is a high risk situation which should be avoided whenever possible.

Female↗

Ovarian response during IVF-embryo transfer cycles after laparoscopic ovarian cystectomy for endometriotic cysts of >3 cm in diameter.

BACKGROUND: Ovarian response during IVF cycles after laparoscopic ovarian cystectomy for endometriotic cysts >3 cm is controversial. A retrospective study was designed to study this problem. METHODS: At laparoscopy, endometriomas >3 cm were treated by ovarian cystectomy, whilst adhesions and peritoneal endometriosis were treated using conventional techniques. Ovarian stimulation was achieved with clomiphene and gonadotrophins or with gonadotrophins after a desensitization with gonadotrophin-releasing hormone agonists. Three groups of patients were retrospectively selected from an IVF-embryo transfer database: patients who underwent laparoscopic ovarian cystectomy for an endometrioma >3 cm (Group A, n = 41), patients with endometriosis without ovarian endometrioma (Group B, n = 139) and patients with tubal infertility (Group C, n = 59). RESULTS: The groups did not differ in age. In the first IVF cycle, the mean (+/- SD) numbers of oocytes and of embryos were 9.4 +/- 6.2 and 4.7 +/- 3.6 respectively in group A and 11.6 +/- 7.5 and 5.1 +/- 4.9 in group B (not significant). The results did not differ in cycles 2 and 3 or when compared according to age. No difference was found when comparing patients with endometriosis and patients with tubal infertility. CONCLUSION: The number of oocytes and embryos obtained was not significantly decreased by laparoscopic cystectomy, suggesting that in experienced hands this procedure may be a valuable surgical tool for the treatment of large ovarian endometriomas. However, great care must be taken to avoid ovarian damage.

Adult↗

Risk of spread of ovarian cancer after laparoscopic surgery.

The incidence of the spread of ovarian cancer after laparoscopic surgery is difficult to establish from the current literature. The prognosis incidence of a trocar site metastasis without peritoneal dissemination is not known. Data from general surgeons in prospective studies from a single institution suggested that in colon cancer the risk is low, whereas it seems to be much higher in multicentric studies of undiagnosed gallbladder cancer. Experimental studies suggested that laparoscopy has advantages and disadvantages. However, the risk of dissemination is high when a large number of malignant cells and a carbon dioxide pneumoperitoneum are present, a situation encountered when managing adnexal tumours with large vegetations. Animal studies will allow the development of a peritoneal environment adapted to the treatment of cancer. The ovary is an intraperitoneal organ and ovarian cancer a peritoneal disease, so the risk of peritoneal spread may be higher in ovarian cancer than in other gynecological cancers. A careful preoperative evaluation appears to be the best way to prevent these risks. It should also be used to choose which patient should be operated by which surgical team. The second step is a careful and cautious laparoscopic diagnosis, so that more than 98% of ovarian cancers encountered can be treated immediately and effectively. The laparoscopic management of ovarian cancer remains controversial; it should be performed only in prospective clinical trials. Until the results of such studies become available, an immediate vertical midline laparotomy remains the gold standard if a cancer is encountered.

Animals↗

[Prevention of peritoneal adhesions].

Peritoneal adhesions are a major problem for health and economy. An adequate and atraumatic surgical technique is essential in the prevention of peritoneal adhesions. Laparoscopic microsurgery should be developed and promoted. The following conclusions can be proposed about the treatments available Adequately designed clinical studies are too rare. Future studies are necessary to obtain information on pregnancy and pain as primary outcomes. Cost implications of adhesion prevention treatments also have to be addressed.

Animals↗

Cancer and laparoscopy, experimental studies: a review.

OBJECTIVE: To review the experimental studies on laparoscopy and cancer and to propose guidelines for the clinical management of gynecologic cancer. METHODS: The literature in MEDLINE was searched from January 1992 to December 1998 using the terms 'cancer', 'laparoscopy' and 'experimental or animal study'. Cross-referencing identified additional publications. Abstracts and letters to the editor were excluded. All the relevant papers were reviewed. RESULTS: Depending on the model used, controversial results have been reported on the incidence of trocar site metastasis when comparing CO(2) laparoscopy and laparotomy. In contrast, the following conclusions can be proposed: (i) tumour growth after laparotomy is greater than after endoscopy; (ii) tumour dissemination is worse after CO(2) laparoscopy than after laparotomy; (iii) some of the disadvantages of CO(2) laparoscopy may be treated using local or intravenous treatments or avoided using other endoscopic exposure methods, such as gasless laparoscopy. CONCLUSIONS: The laparoscopic treatment of gynecologic cancer has potential advantages and disadvantages, and may only be performed in prospective clinical trials. The risk of dissemination appears high when a large number of malignant cells are present. Adnexal tumours with external vegetations, and bulky lymph nodes should be considered as contra-indications to CO(2) laparoscopy.

Animals↗

Successful transfer of frozen-thawed embryos obtained immediately before radical surgery for stage IIIa serous borderline ovarian tumour: case report.

A stage IIIA borderline serous ovarian tumour was treated conservatively by laparoscopy to preserve the fertility of a 21 year old nulligravid woman. Six months later, recurrent lesions were resected. An 'urgent' IVF was performed to obtain frozen embryos. Oncological treatment was then completed by radical surgery with uterine conservation. Fifteen months later, two thawed embryos were successfully transferred and the patient delivered one baby. From this observation, the authors discuss an alternative to oocyte donation in cases of bilateral ovariectomy for stage IIIA borderline serous ovarian tumour.

Adult↗

[Ovarian transposition by laparoscopy in young women before curietherapy for cervical cancer].

OBJECTIVES: To evaluate the place of ovarian transposition by laparoscopy in an effort to preserve ovarian function without compromising oncological safety among young women requiring intravaginal brachytherapy before surgery for cervical cancer. MATERIAL AND METHODS: The series was represented by 20 cases, all FIGO stage I squamous cell malignant diseases of the cervix. Mean age: 32 years (range 23-40). Oophoropexy (7 instances) or lateral high ovarian transposition (13 instances) was performed by laparoscopy, just before brachytherapy using cesium 137. RESULTS: Continued hormonal function was achieved in 58% of the available cases, 50% (3/6) after oophoropexy, 68% (8/11) after ovarian transposition. Mean follow-up was 8.5 years (range 5-13). The mean radiation dose absorbed by the displaced ovary was 2.6 Gy (range 1. 2-5.9). CONCLUSION: Ovarian transposition through laparoscopy before brachytherapy should be advised for selected stage I squamous type malignant tumor size 2 cm without lymphatic/vascular channel invasion by neoplastic emboli and without lymph node involvement. This procedure has been abandoned in our institution, instead of this, primary surgical treatment is accomplished (laparoscopically-assisted vaginal) radical hysterectomy is associated with orthotopic ovarian conservation.

Adult↗

[Adenomyosis].

Adenomyosis keeps a strange and unknown feature. Indeed, therefore of an unclear physiopathology, the difficult diagnosis due to the lack of specificity of symptoms and the absence of effective conservative treatment, adenomyosis is still tightly bond at hysterectomy. Even so, a recent literature study shows that the fatality of hysterectomy could go away. The progress in imagery diagnosis and myometrial biopsy allows the use of less radical treatments. So a group of young patients with an earlier diagnosis appears, permitting to use with effectiveness the hormonal therapy or endoscopic surgery. Hysterectomy at once is saved for more than 40 years old patients, with a considerable uterine volume and deep lesions. In the others cases, the radical procedure remains the solution for the failure of conservative treatment.

Adult↗

Minilaparoscopic hysterectomy.

Minilaparoscopic surgery was performed in a 38-year-old woman scheduled for hysterectomy and ovarian cystectomy. Image resolution was similar to that of conventional laparoscopy. There were no intraoperative or postoperative complications. Since it has many advantages and few complications, minilaparoscopy appears to be an attractive way to decrease morbidity associated with conventional laparoscopy. (J Am Assoc Gynecol Laparosc 5(4):97-100, 1998)

Adult↗

Possible involvement of arylamine N-acetyltransferase 2, glutathione S-transferases M1 and T1 genes in the development of endometriosis.

Wide inter-individual variation of expression of compound metabolic enzymes is determined by polymorphism and may predispose the development of diseases provoked by environmental factors. The combined analysis of phase II detoxification system genes: arylamine N-acetyltransferase 2 (NAT2), and glutathione S-transferases (GST) M1 and T1 was carried out in patients with minimal/mild (group I; n = 36) and moderate/severe endometriosis (group II; n = 29) and controls (n = 72) of French origin, using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The results show a significant difference between patients and controls with regard to NAT2 gene polymorphism (P < 0.05). This is mainly due to the high percentage of slow acetylator genotypes (SA) in patients compared with controls (60.0 versus 38.9%; P < 0.02) with a distinct preponderance in subjects with minimal/mild endometriosis (69.4%, P < 0.005) where there is a significantly elevated frequency of slow allele S1 (NAT2*5) (P = 0.05). Significantly increased proportions of GSTM1-deficient genotypes were found in both groups of patients, in comparison with the controls (75.0 and 79.3% versus 45.8%; P < 0. 0001). A preponderance of GSTT1-negative subjects among patients was also detected, but did not appear significant. We suggest the involvement of both NAT2 and GSTM1 detoxification system genes in the pathogenesis of endometriosis and the possible impact of NAT2 gene polymorphism in the development of different forms of this disease.

Arylamine N-Acetyltransferase↗

Fibrogenesis in peritoneal endometriosis. A semi-quantitative analysis of type-I collagen.

OBJECTIVE: To evaluate the degree of fibrosis in the stroma of peritoneal endometriosis, according to the macroscopic appearance. METHODS: Red and black lesions of peritoneal endometriosis were collected and type-I collagen was immunohistochemically identified. The percentage of the stained area in the stroma was measured using a computerized image analysis system. RESULTS: There was a significant difference in the mean percentage of the total stained area between red and black lesions. CONCLUSION: The amount of type-I collagen is significantly higher in the stroma of black peritoneal lesions than in red peritoneal lesions.

Adult↗

Tumor growth and dissemination after laparotomy and CO2 pneumoperitoneum: a rat ovarian cancer model.

OBJECTIVE: To compare tumor growth, intraperitoneal implantation, and abdominal wall metastasis after laparotomy and CO2 pneumoperitoneum in a rat ovarian cancer model. METHODS: To mimic intraoperative rupture of an ovarian tumor in a syngenic rat ovarian carcinoma model, 10(5) malignant cells were injected intraperitoneally after a 5-cm vertical midline laparotomy or after the insufflation of a CO2 pneumoperitoneum achieved with 4 mmHg or 10 mmHg intra-abdominal pressure. Two weeks later, the intraperitoneal tumor growth and the tumor dissemination were evaluated semiquantitatively with a scoring system. The scores attributed to each organ were added to calculate the dissemination score of each animal. RESULTS: The mean (+/-SD) dissemination score was 83.4+/-12 in the laparotomy group and 67.3+/-16 and 71.9+/-17 in the 4 and 10 mmHg CO2 pneumoperitoneum groups, respectively (P < .01). The scores for the peritoneum were 21.8+/-3.8 in the 10 mmHg pneumoperitoneum group and 18+/-2.4 in the laparotomy group (P < .01). In the laparotomy group, the implant found along the midline scar accounted for a mean of 62.6+/-15% of the peritoneal score, whereas the trocar site metastases did not influence the peritoneal score in the pneumoperitoneum groups. The incidence of wound metastasis was 96% in the laparotomy group and 55% and 54% in the 4 mmHg and 10 mmHg pneumoperitoneum groups, respectively. CONCLUSION: In this model, tumor growth was greater after laparotomy than after laparoscopy, but peritoneal tumor dissemination was more severe after CO2 pneumoperitoneum.

Animals↗

Increased mast cell density in peritoneal endometriosis compared with eutopic endometrium with endometriosis.

PROBLEM: Factors regulating fibrosis in peritoneal endometriosis are poorly understood. We hypothesized that mast cell proteases may play a role in the process of fibrosis in peritoneal endometriosis. As the first step in examining the possible contribution of mast cells to fibrosis, we investigated their distribution in peritoneal endometriosis lesions according to their macroscopic appearance. METHOD OF STUDY: Mast cells were identified by immunohistochemistry using monoclonal antibody against mast cell tryptase on formalin-fixed, paraffin-embedded sections. Mast cell density (mean mast cell count per 0.13 mm2 of stroma) was measured using a computerized image analysis system. RESULTS: Mast cell density was significantly increased in black peritoneal lesions compared with red peritoneal lesions in endometriosis. CONCLUSIONS: Mast cells may be involved in the pathogenesis of peritoneal endometriosis.

Chymases↗

Angiogenesis in endometriosis.

We evaluated angiogenesis in eutopic endometrium and ectopic endometrium from patients with endometriosis. Microvessels were identified by immunohistochemistry using anti-von-Willebrand factor antibody and vascular parameters were measured using a computerized image analysis system. No relationship was observed between vascular density and type of endometriotic lesion. Heterogeneity in vascular density was observed in different lesions within the same patient. Between red and black peritoneal lesions a significant difference was observed in the frequency distribution of luminal diameter. In black lesions the variability of luminal diameter was decreased and most microvessels were less than 20 mm in diameter. We suggest that the frequency distribution of microvessel luminal diameter of red and black peritoneal lesions may be different and should be important when studying the regulation of angiogenesis in endometriotic implants.

Adult↗

[Laparoscopic surgery and pregnancy].

Laparoscopic surgery during pregnancy is still under evaluation. Most of published papers include few patients. The literature review reveals that laparoscopic cholecystectomy is the most performed procedure, followed by appendectomy and adnexal surgery. Intra-operative measures (surgical and medical) to prevent complications, appear of paramount importance. Results of published series suggest that laparoscopy during pregnancy is feasible and safe for both mother and fetus. Nevertheless, all studies are retrospective and included few patients, therefore drawing a definitive conclusion is questionable. On the other hand, experimental studies suggested a deleterious effect of pneumoperitoneum on fetus (fetal acidosis). But clinical relevance of these experiments is controversial and their results are conflicting. It would be tempting to conclude that laparoscopic surgery is the "gold standard" during pregnancy but the lack of strong scientific evidence does not allow, at present, to conclude that this conclusion is evidence based. Prospective trials or registries are needed to confirm the encouraging preliminary results in the literature.

Evidence-Based Medicine↗

[Surgical management of adnexal tumors].

Concerning laparoscopy and tumor dissemination, we know from several multivariate analyses that at laparotomy, if the tumor is entirely and immediately removed, the puncture of a stage I ovarian cancer has no influence on the prognosis. In contrast the inadequate surgical management of an undiagnosed ovarian cancer may worsen the prognosis. The diagnosis is the key step. To be able to immediately and completely treat an ovarian cancer when managing an ovarian tumor surgically, Laparoscopic diagnosis is safe and reliable when used cautiously. The surgical diagnosis may and should probably be performed by laparoscopy whatever the ultrasonographic appearance of the tumor. Masses diagnosed as suspicious at surgery should be treated by immediate laparotomy, since the results of laparoscopic treatment of an ovarian cancer are not known. In young patients, conservative surgery is the main advantage of laparoscopy, and should be achieved in most benign masses. The recent progresses of in vitro fertilization should be taken into account when managing an ovarian tumor in a patient who wishes to become pregnant. Frozen sections are useful, when treating highly suspicious masses, allowing an immediate staging and avoiding the disadvantages of a second surgical procedure. Whenever a malignant tumor has been missed at laparoscopy, restaging is required and should be considered to be an oncologic emergency.

Adult↗

Prediction of pregnancy in infertile women based on the American Society for Reproductive Medicine's revised classification of endometriosis.

OBJECTIVE: To estimate the empirical relationship between the revised American Society for Reproductive Medicine's classification of endometriosis and pregnancy rates after treatment. DESIGN: Retrospective analysis. PATIENT(S): Patients seen by four practicing physicians. INTERVENTION(S): Medical and/or surgical therapy for endometriosis. MAIN OUTCOME MEASURE(S): Pregnancy defined as ongoing or delivered. RESULT(S): There were no significant differences in pregnancy rates across stages of endometriosis. There was a slight decline in pregnancy rates among patients with Stage IV endometriosis, but statistical significance was not achieved. CONCLUSION(S): The use of an arbitrary weighted system for assigning scores to individual categories of disease, or for computing a total score, has limited the overall effectiveness of the classification system to predict pregnancy.

Adult↗