Neoadjuvant therapy or upfront surgery? A systematic review and meta-analysis of T2N0 esophageal cancer treatment options.

BACKGROUND: Esophageal carcinoma usually shows poor long-term survival rates, even when esophagectomy, the standard curative treatment is performed. As a result, there has been increasing interest in the neoadjuvant therapy, which could potentially downstage cancer, eliminate micrometastasis and ergo increase resectability and curative (R0) resection. Currently, for the earliest stage esophageal cancers, most guidelines point out to the role of endoscopic treatment, and for T1bN0 upfront surgery. For locally advanced cases, several studies have demonstrated the benefits of neoadjuvant therapy to increase resectability. For clinical stage T2N0 esophageal cancer, there is no consensus as to the optimal treatment strategy. METHODS: A systematic review and meta-analysis was performed to compare neoadjuvant therapy with surgery alone on clinical stage T2N0 esophageal cancer patients, concerning overall survival, recurrence, post-operative mortality, anastomotic leak, and R0 resection rate. RESULTS: For overall survival at the mean follow-up point, the neoadjuvant therapy was not associated to a higher probability of survival than upfront surgery in cT2N0 patients (risk difference: 0.00; 95% CI: -0.09, 0.09). There was no difference between neoadjuvant therapy and primary surgery concerning recurrence (risk difference: 0.21; 95% CI: -0.03, 0.45); perioperative mortality (risk difference: 0.00; 95% CI: -0.02, 0.01); and risk for anastomotic leak (risk difference: -0.08; 95% CI: -0.21, 0.05). Pooled data showed that neoadjuvant therapy was associated to a higher risk for positive margins after resection (risk difference: 0.04; 95% CI: 0.02, 0.06). CONCLUSIONS: This review showed that neoadjuvant therapy is not associated to better results than surgery alone, for the management of clinical stage T2N0 esophageal cancer patients, concerning overall survival, recurrence rate, perioperative mortality, anastomotic leak, and seems to be associated to a higher risk for resection with positive margins.

Low-power laser therapy for repairing acute and chronic-phase bone lesions.

To evaluate the therapeutic activity of low-power laser (InGaAlP: 670 nm/30 mW), at doses of 90 J/cm(2), on the process of acute and chronic-phase repair of bone lesions of Wistar rats. Sixty-three adult males were divided into nine groups subjected to bone injury, in order to form the following treatments: T1 (control); T2 (acute-phase); T3 (chronic-phase) which were subdivided into three subgroups (n=7), analyzed on the 9th, 17th and 28th days post-surgery, after a period of daily treatment with laser. The animals with acute-phase treatment presented a more extensive endochondral ossification process. Laser-treated animals showed significant increases in serum alkaline phosphatase levels and had an effect on biomechanical property, resulting in a gradual increase in bone stiffness. Laser therapy aided the bone consolidation process and favored the physiopathologic mechanisms involved in bone tissue repair, and its effects were more prominent when treatment started during the acute phase of the injury.

Clinical and electrocardiographic evaluation during experimental toad poisoning in dogs

Accidents involving toad poisoning are frequent and dogs are the most common victims; they become poisoned by biting or ingesting a toad. When released in the organism, the venom is absorbed by both the oral mucosa and the digestive tract, initiating its toxic action. The aim of this work was to evaluate the clinical and electrocardiographic aspects of dogs subjected to experimental toad poisoning, as well as their response to treatment with propranolol. Twenty dogs were divided into two groups, a control group (n = 5) and a poisoned group (n = 15). After general anesthesia, the control group received a placebo, while the poisoned group received a venom aliquot through an orogastric tube. Results were tested through multivariate analysis (p < 0.05). The animals in the poisoned group had gastrointestinal symptoms including emesis, intense salivation, hyperemic or congested oral mucosa and pasty diarrhea. Non-responsive mydriasis, nystagmus, depression, stupor, tachypnea, opisthotonus and ataxia were also manifested by 100 percent of the poisoned animals. Affected dogs had an increase in blood pressure, statistically significant throughout study. Five poisoned animals developed ventricular tachycardia and were treated with propranolol (0.5 mg/kg IV). All propranolol-treated animals returned to normal sinus rhythm, which evidences the efficacy of this drug to treat ventricular arrhythmias caused by toad venom.