Ron Lavy
Tel Aviv University
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Featured researches published by Ron Lavy.
Gastric Cancer | 2010
Igor Rabin; Bar Chikman; Ron Lavy; Natan Poluksht; Zvi Halpern; Ilan Wassermann; Ruth Gold-Deutch; Judith Sandbank; Ariel Halevy
BackgroundSentinel lymph node (SLN) mapping has been recently introduced to the field of gastric cancer. To the best of our knowledge, no study has dealt with the accuracy of SLN mapping according to the T stage of the primary tumor. The aim of the present study was to evaluate SLN status according to the T stage of the primary tumors.MethodsEighty patients with gastric cancer underwent SLN mapping with patent blue dye during gastric resection.ResultsForty-seven patients underwent distal subtotal gastrectomy; 17 patients, proximal gastrectomy; 14, total gastrectomy; and 2, gastric stump resection. SLNs were stained in 61/80 patients (76.3%). The number of stained SLNs varied from 1 to 16 (mean, 3.3). Patients undergoing proximal gastrectomy had a mean of 3 stained SLNs, whereas patients undergoing distal subtotal gastrectomy had a mean of 2.8 stained SLNs. In 55/61 patients (90.2%) with stained SLNs a positive correlation was found between the presence of metastases and stained or non-stained SLNs. Ten out of 11 patients (90.9%) with T1 tumors (mean, 3.27 SLNs per patient) and 15/17 patients with T2 tumors (88.2%; mean, 3 SLNs per patient) had stained SLNs as compared to only 33/48 (68.8%) of patients with T3 tumors (mean, 3.3 SLNs per patient). The positive predictive value of the SLN mapping was 100%, the negative predictive value was 76.9%, and sensitivity was 85.4%.ConclusionWhile in T1 and T2 tumors sentinel node mapping may be of assistance in the decision-making process regarding the extent of lymphadenectomy (sensitivity, 100%; negative predictive value, 90%-100%), SLN mapping in patients with T3 tumors will be misleading in a third of the patients and should not be attempted.
Journal of The American College of Surgeons | 2014
Igor Jeroukhimov; Itay Wiser; Evgeny Karasic; Vladimir Nesterenko; Natan Poluksht; Ron Lavy; Ariel Halevy
BACKGROUND Chronic pain after inguinal hernia repair occurs in 16% to 62% of patients. The underlying mechanism probably involves sensory nerve damage and abnormal healing that might be influenced by the materials chosen for the procedure. We hypothesize that nonabsorbable sutures used for mesh fixation to the surrounding tissues are associated with higher rates of chronic groin pain after surgery. STUDY DESIGN We conducted a single-blind randomized clinical trial to compare the effect of absorbable braided sutures (Vycril; Ethicon) and nonabsorbable monofilament sutures (Prolene; Ethicon) used in inguinal hernia repair on the rate of chronic pain. We assessed chronic pain using a 4-point verbal-rank scale during a 1-year postoperative follow-up period. RESULTS Study groups included 100 patients in each group. No age, sex, or hernia-side differences were observed between the study groups. Chronic pain rate after surgery was higher in the nonabsorbable monofilament suture group compared with the absorbable braided suture group (37 vs 26 patients; p = 0.056). Time to pain disappearance was longer in the nonabsorbable monofilament suture vs the absorbable braided suture group (115.3 days; 95% CI, 88-142.7 vs 77.4 days; 95% CI, 54.3-100.3; p = 0.038, respectively). A 1-year age increment reduces the risk for chronic pain occurrence by 2.2% (odds ratio = 0.978%; 95% CI, 0.961-0.995; p = 0.013). The use of nonabsorbable sutures increases the risk for chronic pain in 94.9% compared with absorbable sutures (odds ratio = 1.949; 95% CI, 1.039-3.658; p = 0.038). CONCLUSIONS Nonabsorbable suture use in inguinal hernia repair is associated with a higher rate of chronic pain and a longer time to pain disappearance as compared with absorbable sutures.
Gastric Cancer | 2013
Ron Lavy; Andronik Kapiev; Natan Poluksht; Ariel Halevy; Lital Keinan-Boker
BackgroundGastric cancer is the fourth most common malignancy worldwide. The incidence trends and mortality rates of gastric cancer in Israel have not been studied in depth. The aim of our study was to try and investigate the aforementioned issues in Israel in different ethnic groups.MethodsThis retrospective study is based on the data of The Israel National Cancer Registry and The Central Bureau of Statistics. Published data from these two institutes were collected, summarized, and analyzed in this study.ResultsAround 650 new cases of gastric cancer are diagnosed yearly in Israel. While we noticed a decline during the period 1990–2007 in the incidence in the Jewish population (13.6–8.9 and 6.75–5.42 cases per 100,000 in Jewish men and women, respectively), an increase in the Arab population was noticed (7.7–10.2 and 3.7–4.2 cases per 100,000 in men and women, respectively). Age-adjusted mortality rates per 10,000 cases of gastric cancer decreased significantly, from 7.21 in 1990 to 5.46 in 2007, in the total population. The 5-year relative survival showed a slight increase for both men and women.ConclusionThere is a difference in the incidence and outcome of gastric cancer between the Jewish and Arab populations in Israel. The grim prognosis of gastric cancer patients in Israel is probably due to the advanced stage at which gastric cancer is diagnosed in Israel.
International Journal of Surgery | 2010
Zahar Shapira; Leonid Feldman; Ron Lavy; Joshua Weissgarten; Zoya Haitov; Ariel Halevy
BACKGROUND Many patients with various types of colonic pathology undergo invasive procedures that require mechanical bowel preparation. The most commonly used medications for bowel preparation include phosphate-containing drugs which are low cost and enable this procedure to be performed in an outpatient setting, as opposed to other medications, such as polyethylene glycol. Recent studies have suggested that freely using phosphate-containing drugs might lead to renal function impairment in a small group of patients. Despite this, many surgeons still use these drugs to prepare their patients. We conducted a comparative study to check the side effects of phosphate-containing drugs compared to polyethylene glycol when used for bowel cleansing. METHODS We conducted a double blind prospective randomized study that included 40 patients undergoing surgery for colonic pathology, all of whom underwent bowel cleansing (20 with sodium phosphate and 20 with polyethylene glycol). During the perioperative course, electrolyte parameters were collected from serum and urine and compared between the two groups of patients. RESULTS Changes in electrolyte and metabolic parameters were shown in both groups, but more prominently in patients prepared with sodium phosphate. In addition, early signs of renal function impairment appeared in this group. The differences in metabolic and electrolyte changes between the two groups were statistically significant. CONCLUSIONS On the basis of this study, we propose that the wide use of phosphate-containing drugs for colonic preparation might be dangerous for the specific group of patients that is prone to develop renal failure or electrolyte abnormalities.
International Journal of Surgery | 2014
Ron Lavy; Yehuda Hershkovitz; Andronik Kapiev; Bar Chikman; Zahar Shapira; Natan Poluksht; Nirit Yarom; Judith Sandbank; Ariel Halevy
BACKGROUND The number of lymph nodes harvested during gastrectomy depends on the extension of lymphadenectomy and the method of lymph node retrieval. AIM The objective of this study was to evaluate two methods of lymph node retrieval in specimens of gastric cancer. METHODS The number of lymph nodes was compared using two different techniques. The technique used in the first group was manual dissection following formalin fixation, and the techniques used in the second group was fat-clearing by acetone. RESULTS Both groups were comparable for demographic and pathological variables. The average number of harvested nodes was 19.3 ± 10 for the manual group as compared to 26.1 ± 14 in the acetone group (P = 0.003). The differences in the average number of positive nodes did not reach statistical significance (4.6 compared to 6.9 nodes). CONCLUSION The acetone clearing technique enables the evaluation of a larger number of nodes. An increase, but statistically non significant, number of positive nodes was noted in the acetone group.
Journal of Surgical Oncology | 2012
Ariel Halevy; Ron Lavy; Itzhak Pappo; Tima Davidson; Ruth Gold-Deutch; Igor Jeroukhimov; Zahar Shapira; Ilan Wassermann; Judith Sandbank; Bar Chikman
In two‐thirds of breast cancer patients undergoing reoperation no residual tumor will be found. A scoring system for selection of patients who might benefit from relumpectomy is proposed.
Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2012
Ron Lavy; Inbar Gatot; Ilya Markon; Zahar Shapira; Bar Chikman; Laurian Copel; Ariel Halevy
Background: Pancreatic cancer (PC) is an aggressive disease usually diagnosed at an advanced stage. Modern computed tomography can define the subgroup of operable patients. However, minimal peritoneal deposits can be undetected even by modern computed tomography protocols. Aim: To diagnose those patients who are not operable because of a peritoneal spread using diagnostic laparoscopy (DL), thus avoiding unnecessary laparotomies. Methods: A retrospective study was conducted on 52 consecutive patients with PC scheduled for curative pancreatic surgery. Results: Out of 52 patients who underwent DL, peritoneal spread was diagnosed in 5 patients and these patients were denied surgery. Laparoscopy did not detect 2 other patients with peritoneal spread. Conclusions: Although the added value of DL in patients with PC is small (around 10% in our series), considering the minimal morbidity and costs attributed to this procedure, we believe that it should be adopted as a routine approach.
Journal of Surgical Education | 2015
Ron Lavy; Ariel Halevy; Yehuda Hershkovitz
OBJECTIVE Laparoscopic cholecystectomy (LC) has been the gold standard for surgical treatment of gallbladder disease since 1980. This laparoscopic surgical procedure is one of the first to be performed by general surgery residents. There is a learning curve required to excel at performing LC. During this period, the operation needs to be performed under the supervision of a senior surgeon. The purpose of this study was to compare LC performed by residents with that performed by senior surgeons using the following parameters: operative time, conversion rate, complication rate, and mean length of hospital stay. METHODS This retrospective study included 1219 patients who underwent elective LC in our institute-788 operated on by a senior surgeon and 431 by a resident. RESULTS The mean operative time was 39 ± 19 minutes. There was a significant difference between the groups, as the mean operative time for the resident group was 49.9 ± 13 compared with 33.7 ± 6 for the senior surgeon group. The overall conversion rate was 2.1%, the complication rate was 2.2%, and the mean length of hospital stay was 1.5 days. There were no statistically significant differences between the groups for these parameters. CONCLUSIONS The only significant difference between the groups was a longer operative time, as the conversion rate, complication rate, and mean length of stay were the same. Therefore, it is safe for LC to be performed by residents supervised by a senior surgeon.
World Journal of Gastrointestinal Surgery | 2014
Ron Lavy; Andronik Kapiev; Yehuda Hershkovitz; Natan Poluksht; Igor Rabin; Bar Chikman; Zahar Shapira; Ilan Wasserman; Judith Sandbank; Ariel Halevy
AIM To investigate the influence of tumor grade on sentinel lymph node (SLN) status in patients with gastric cancer (GC). METHODS We retrospectively studied 71 patients with GC who underwent SLN mapping during gastric surgery to evaluate the relationship between SLN status and tumor grade. RESULTS Poorly differentiated tumors were detected in 50/71 patients, while the other 21 patients had moderately differentiated tumors. SLNs were identified in 58/71 patients (82%). In 41 of the 58 patients that were found to have stained nodes (70.7%), the tumor was of the poorly differentiated type (group I), while in the remaining patients with stained nodes 17/58 (29.3%), the tumor was of the moderately differentiated type (group II). Positive SLNs were found in 22/41 patients in group I (53.7%) and in 7/17 patients in group II (41.2%) (P = 0.325). The rate of positivity for the SLNs in the two groups (53.7% vs 41.2%) was not statistically significant (P = 0.514). CONCLUSION Most of our patients were found to have poorly differentiated adenocarcinoma of the stomach and there was no correlation between tumor grade and SLN involvement.
International Journal of Surgical Pathology | 2016
Michal Braha; Bar Chikman; Liliana Habler; Zahar Shapira; Sergey Vasyanovich; Gleb Tolstov; Ariel Halevy; Judith Sandbank; Ron Lavy
Host-defense mechanisms may have an important role in predicting the outcome of colorectal cancer patients. We designed our study to evaluate the possible prognostic significance of the presence of lymphocytic infiltration (LI) and subgroups of lymphocytes (CD3 and CD20) in the primary tumors. We randomly selected 195 patients operated for colorectal carcinoma from a larger cohort of 1527 patients with colorectal cancer. Histological slides were blindly reevaluated for the presence of LI that was graded 0 to 3. Immunohistochemical phenotyping of the lymphocytes was performed only for tumors with LI score 3 and included antibodies CD3 and CD20. CD3 and CD20 immunostaining were graded in the same manner as LI. The mean duration of follow-up was 63.8 months. The distribution of patients with colorectal cancer according to LI scores was as follows: score 0, 20/195 (10.2%); score 1, 61/195 (31.3%); score 2, 78/195 (40%); and score 3, 36/195 (18.5%). There was no correlation between any clinicopathological pattern and LI. Score 3 staining for CD3 was more common than for CD20 (64.7% vs 8.8%, P < .0001). Prominent lymphocytic infiltration (score 3) was associated with better disease-free survival (P = .062). Recurrence was diagnosed among 2/22 (9.1%) patients with prominent CD3 staining versus 62/171 (36.2%) of all other patient groups (P = .054) and they correspondingly had better disease-free survival (P = .018). It seems we can identify a group of patients with colorectal cancer who have an excellent prognosis according to a single immunological test unrelated to other known prognostic factors.