Expression of multidrug-resistance P-glycoprotein (MDR1) in human brain tumors.

Multidrug resistance (MDR) is associated with the expression of P-glycoprotein (P-gp), an ATP-dependent transporter which expels anti-cancer drugs from cells. In the present study, MDR1 P-gp was immunodetected by Western blot analysis in 60 human brain tumors, including meningiomas, schwannomas, low-grade gliomas (astrocytomas, pilocytic astrocytomas) and high-grade gliomas (anaplastic astrocytomas, glioblastomas and anaplastic oligodendrogliomas). Most samples from primary tumors expressed P-gp at the same levels as normal brain tissue except for schwannomas, in which levels were reduced by 65%, and meningiomas, in which levels were more than 10-fold higher in 7 of 10 samples. P-gp levels were 70% and 95% lower in brain metastases from melanomas and lung adenocarcinomas, respectively, than in normal brain tissue. These results indicate that the majority of primary brain tumors express MDR1 P-gp and that its high expression levels in meningiomas may be a marker for this type of brain tumor.

Clinical usefulness of intravenous human immunoglobulins in invasive group A Streptococcal infections: case report and review.

The spectrum of invasive Streptococcus pyogenes (group A streptococcus) infections includes bacteremia, toxic shock syndrome, and necrotizing fasciitis or myositis. We report the successful use of intravenous immunoglobulins in conjunction with antibiotics and surgery in a case of necrotizing myositis, toxic shock, and bacteremia. A literature review revealed that three other patients with invasive group A streptococcal infections had been treated with immunoglobulins: one adult patient had toxic shock syndrome, one had necrotizing fasciitis, and one child had septic arthritis. On the basis of this report and the review, we suggest that intravenous immunoglobulins may be useful in the treatment of all forms of invasive group A streptococcal infections associated with toxic shock syndrome.

[Thoracic "staging" by videothoracoscopy: a new technique]. / "Staging" thoracique par vidéothoracoscopie: nouvelle technique.

We are describing a technique of pre resectional staging of thoracic neoplasm by video assisted thoracic surgical (VATS) techniques. This method was applied on 27 patients, when the lymph nodes II, III, IV, VII, VIII and IX were biopsied or excised. In two cases (2) we were forced to proceed to open thoracotomy for staging because of extensive adhesion. In the other 25 patients, the surgical staging was the same as the VATS staging in 92% of the cases. This technic has obvious advantages for lower mediastinal nodes (100%). VATS should be considered among other staging procedure for thoracic neoplasms.

[Angioscopy in peripheral vascular surgery]. / Angioscopie en chirurgie vasculaire périphérique.

At Saint-Luc's Hospital of Montreal, between January 1, 1990 and February 1, 1991, 47 angioscopic procedures were done in 43 patients submitted to peripheral vascular reconstructions. The purpose of the study was to evaluate the role of angioscopy during those procedures. The operations were as follows: twenty femoropopliteal bypasses done with reversed saphenous vein, 15 done with in situ saphenous veins and 10 done with synthetic grafts. Two patients had popliteal embolectomies. Seventeen percent of the cases showed technical problems with the use of controlled angioscopy and were subsequently corrected. Three residual valves and one unsuspected venous stenosis were found in 15 in situ grafts, for a total of 27% correctible defects. In the reversed saphenous group, one case of venous sclerosis and one case of anastomotic stenosis were found for a total of 10%. For the synthetic grafts group we found an intimal flap distal to the anastomosis in one case (10%). Finally, we found a significant residual clot in one case (50%) after embolectomy. The technique of angioscopy is simple, the equipment reliable, and the learning period is short. Angioscopy is a very useful approach and should be readily available in the armamentarium of every vascular surgeon.

Multiple primary lung carcinomas: prognosis and treatment.

From 1955 to 1990, 111 patients have been treated for multiple primary lung carcinomas. Criteria for diagnosis were: (1) different histology (n = 44); or (2) same histology, but disease-free interval at least 2 years (n = 39), origin from carcinoma in situ (n = 19), or metachronous disease in different lobe (n = 9) with no cancer in common lymphatics or extrapulmonary metastasis at the time of diagnosis. The second cancer was synchronous in 33 patients (30%) and metachronous in 78 (70%). Metachronous disease developed at a median interval of 48 months. Five-year survival for patients with metachronous and synchronous disease from the time of initial diagnosis of cancer was 70% and 44%, and 10-year survival was 42% and 23%, respectively. Survival after the development of a metachronous lesion was 23% at 5 years. Survival from the time of initial diagnosis was significantly better for metachronous versus synchronous, late (24 month disease-free interval) versus early metachronous disease, and adenocarcinoma versus epidermoid carcinoma. The first cancer was completely resected in 103 patients (93%), but complete resection of a metachronous tumor was possible in only 54 patients (69%). Complete resection of second primary cancers resulted in significantly (p less than 0.0001) prolonged 5-year survival compared with incomplete resection (38% versus 9%). Excluding patients requiring pneumonectomy, initial resection limited subsequent resection in only 7 patients (9%) with metachronous disease. We conclude that patients surviving treatment of primary lung cancers require lifelong screening for multiple primary lung carcinoma, and complete resection is recommended whenever possible.

Why remove an infected aortofemoral graft?

The radical treatment of infected vascular grafts is a major procedure with a high mortality and loss of limb. The authors review their experience with 13 consecutive cases of infected aortofemoral grafts treated conservatively during an 11-year period. The treatment consisted of wide incision and drainage of the infected area followed by assiduous irrigation with an antiseptic or antibiotic solution. In 10 patients the inguinal wound healed and the prosthesis was reincorporated; 8 of the 10 had a patent prosthesis and the treatment was considered successful, while 2 needed further surgery. Three patients died of hemorrhage or sepsis. Follow-up ranged from 8 to 144 months (mean 77 months). Two patients had a false aneurysm 3 and 7 years after wound healing. The results compare favourably with those of radical treatment. The authors believe a conservative approach must always be tried as the first step in the management of infected vascular prostheses. The gratifying results observed in their series, in both the short and long term, support this conservative approach, which is a satisfying alternative to radical operations with their high mortality and morbidity.

Celiac compression syndrome.

The authors present their experience at the Hôpital St-Luc in Montreal with seven patients who had celiac compression syndrome. All underwent section of the median arcuate ligament to free the celiac axis and resection of the connecting nerve fibers of the solar plexus (periarterial neurectomy). At a mean follow-up of 36 months all patients were asymptomatic. In some cases, extrinsic compression of the celiac axis by the arcuate ligament can explain upper abdominal plain. An epigastric bruit in the presence of a normal digestive tract is an indication for lateral aortography to detect extrinsic compression. The pain in this syndrome cannot be explained solely on hemodynamic grounds; surgical treatment should include release of the celiac axis and complete periarterial neurectomy.

Alkaline reflux gastritis: Roux-en-Y diversion is effective.

Even though controversy persists over the physiopathology of alkaline reflux gastritis, Roux-en-Y diversion is a well-accepted surgical treatment and was used in 23 patients over a 6-year period at the Hôpital St-Luc in Montreal. Of the 23 patients, 21 had complete relief of symptoms. Objective criteria for the selection of patients who would benefit from operation are still to be defined. The authors discuss the physiopathology through an extensive review of the literature.

Arteriography and pancreatic disease.

In the last 10 years, 605 celiomesenteric arteriographic examinations were done at Hôtel-Dieu de Montréal, including 236 for suspected pancreatic disease. Sixty patients with histologic proof of malignant neoplasm had a positive arteriographic examination while 136 had benign disease of the pancreas and 40 others had extra-pancreatic disease. In this series, the sensitivity of arteriography was 88.3% and the specificity 92.6%. In the last 5 years the sensitivity of superselective arteriography was 100%. These results were better than those obtained with noninvasive techniques obtained with noninvasive techniques such as computerized axial tomography, ultrasonography and duodenography. The authors conclude that arteriography and particularly superselective arteriography is an excellent method for evaluating patients with suspected pancreatic cancer.