Laser-writable high-k dielectric for van der Waals nanoelectronics.

Similar to silicon-based semiconductor devices, van der Waals heterostructures require integration with high-k oxides. Here, we demonstrate a method to embed and pattern a multifunctional few-nanometer-thick high-k oxide within various van der Waals devices without degrading the properties of the neighboring two-dimensional materials. This transformation allows for the creation of several fundamental nanoelectronic and optoelectronic devices, including flexible Schottky barrier field-effect transistors, dual-gated graphene transistors, and vertical light-emitting/detecting tunneling transistors. Furthermore, upon dielectric breakdown, electrically conductive filaments are formed. This filamentation process can be used to electrically contact encapsulated conductive materials. Careful control of the filamentation process also allows for reversible switching memories. This nondestructive embedding of a high-k oxide within complex van der Waals heterostructures could play an important role in future flexible multifunctional van der Waals devices.

New routes to the functionalization patterning and manufacture of graphene-based materials for biomedical applications.

Graphene-based materials are being widely explored for a range of biomedical applications, from targeted drug delivery to biosensing, bioimaging and use for antibacterial treatments, to name but a few. In many such applications, it is not graphene itself that is used as the active agent, but one of its chemically functionalized forms. The type of chemical species used for functionalization will play a key role in determining the utility of any graphene-based device in any particular biomedical application, because this determines to a large part its physical, chemical, electrical and optical interactions. However, other factors will also be important in determining the eventual uptake of graphene-based biomedical technologies, in particular the ease and cost of manufacture of proposed device and system designs. In this work, we describe three novel routes for the chemical functionalization of graphene using oxygen, iron chloride and fluorine. We also introduce novel in situ methods for controlling and patterning such functionalization on the micro- and nanoscales. Our approaches are readily transferable to large-scale manufacturing, potentially paving the way for the eventual cost-effective production of functionalized graphene-based materials, devices and systems for a range of important biomedical applications.

[Spontaneous regression of epithelial thymic tumours]. / Tumeurs épithéliales thymiques de régression spontanée.

INTRODUCTION: Spontaneous regression of an epithelial thymic tumour has been reported but seems extremely rare. Its mechanism is unknown. CASE REPORT: We report two cases of epithelial thymic tumour, either histologically proven or highly suspected on imaging, that regressed spontaneously (partially in one patient and totally in the other). CONCLUSION: Spontaneous regression of an epithelial thymic tumour is very rare but this possibility could lead to clinical and radiological monitoring rather than surgery in selected patients.

Is laparoscopic fiberoptic choledochoscopy for common bile duct stones a fine option or a mandatory step?

BACKGROUND: Because choledochoscopy often is a challenging maneuver, it would be advantageous to define the real utility of its use. This study aimed to compare blind exploration of the common bile duct (CBD) with choledochoscopy-assisted CBD stone removal in terms of patient outcome and complication rate. METHODS: Two groups of patients were prospectively evaluated in a 4-year period. The study participants were 36 men and 27 women randomized to group A (n = 32) for a blind basket procedure or group B (n = 31) for a choledochoscopy-assisted procedure as the first step of laparoscopic CBD stone removal. Patients with preoperatively suspected CBD stones (n = 51) and those with unsuspected stones (n = 12) were included. The two groups did not differ significantly in terms of anagraphics, American Society of Anesthesiology (ASA) score, or previous surgery. All the procedures were performed by surgeons skilled in this surgical field. Choledochoscopy, when used, was always performed with the instrument connected to a camera monitor that had a wide vision, whether in a single-monitor, in a picture-in-picture manner, or with the use of an additional monitor. RESULTS: From March 2004 to April 2008, 63 patients undergoing CBD exploration for stone removal were enrolled in the study. Five of these patients had undergone previous endoscopic retrograde cholangiopancreatography (ERCP)/endoscopic sphincterotomy (ES). The mean operative time was 107 min for group A and 122 min for group B. The mean hospital stay was 3 days for group A and 3.6 days for group B. Clearance of CBD stones was achieved laparoscopically in 62 cases. One patient required open combined transduodenal papilloplasty and transcholedochotomy. In seven cases, blind basket exploration was unable to remove the stones according to the cholangiogram, so choledochoscopy was required. Six patients underwent a transversal coledocothomy for stone removal. A Kehr T-tube was placed in four of these patients. In four group A cases, the papilla was inadvertently passed during the procedure. In six group A cases, including the four aforementioned cases, a high level of amylases was found on postoperative day 1. At this writing, no late complications or stone recurrences have been observed in either group. CONCLUSIONS: The laparoscopic basket blind technique and choledochoscopy are safe and effective for CBD stone removal. However, the latter seems to be better in terms of a higher stone removal rate and fewer minor complications despite its longer operation time. In the authors' opinion, it may be preferable to reserve ERCP for very high-risk patients, taking into account that in addition to the related complications, it results in an approximate 10% rate of recurrent or persistent stones.

Long-term results of laparoscopic adrenalectomy for primary aldosteronism.

BACKGROUND: The management of primary aldosteronism is currently achieved by both medical and surgical treatment. Laparoscopy has in recent years unquestionably become the gold standard in adrenal surgery for benign lesions. This study aims to evaluate our clinical results among patients who underwent laparoscopic adrenalectomy (LA) for primary aldosteronism. METHODS: From January 1994 to January 2006, amid LA series, 59 primary aldosteronism patients were treated in our institution. Patients were 33 males and 26 females with mean age 49.3 yr (19-78). The mean body mass index was 25.9 kg/m2 (20.5-33.3). The mean size of lesion was 2.9 cm (1-5.5). Clinical symptoms were as follows: hypertension and symptomatic/asymptomatic hypokalemia (54), hypokalemia (5). RESULTS: Thirty-five left and 24 right LA were performed. On the left side, 22 procedures were carried out by anterior approach, 9 by anterior submesocolic route, and 4 by means of flank approach. All right procedures were completed by the anterior supine approach. The mean operative time was 103.5 min for left and 92.8 min for right adrenalectomy. There was one major complication, a colonic post-operative fistula, regarding a left adrenalectomy case. The mean post-operative hospital stay was 3 days (1-9). The cure rate of hypertension and hypokalemia was similar to the current literature results. CONCLUSIONS: LA is a safe and effective option in the treatment of primary aldosteronism. Appropriate selection of patients, larger adrenal masses and duration of symptoms are determining factors in the success rate of hypertension management.

The learning curve in laparoscopic adrenalectomy.

BACKGROUND: Laparoscopic adrenalectomy (LA) is the procedure of choice for surgical management of most adrenal tumors. LA learning curve (LC) varies among surgeons and may be influenced by factors depending on surgeon, patient, and lesion peculiarities. The aim of this study was to evaluate the LC by multi-dimensional analysis. METHODS: Between August 1994 and August 2005, 241 LA were performed in our department. Data were prospectively collected. The pre-operative variables evaluated were patient-related (age, gender, body mass index, co-morbidities) and disease-related (histology, size, and side of lesion). Level of experience of surgical team and surgical approach (anterior, flank, submesocolic routes) were evaluated as well. Flank approached and bilateral procedures were excluded, while submesocolic LA, were collected separately. Operating time (OpT), conversion rate (CR), intra-operative and post-operative complications were evaluated. Patient, surgeon, and procedure-related factors involved in LC were investigated by a multi-factorial logistic regression analysis. RESULTS: Body mass index, side, size, histology, technology improvement, and experience of surgical team, evaluated through the progressive series of surgical procedures, were independent predictors of CR and OpT. The CR for right adrenalectomy was 3% (3 cases) compared to 4.2% for left side (6 cases). The submesocolic approach significantly influenced OpT, but not CR. Mean OpT for right and left LA was 83 and 109 min, respectively. Based on surgical experience increase, the OpT and CR flattened their curves, roughly at 30 and 40 procedures for right and left LA, respectively. Post-operative complications did not change considerably throughout the series. Readmission rate within 30 days was negligible. CONCLUSIONS: Manifold factors may affect LC and outcome in LA. Their knowledge may support teaching activities as well as reducing conversion and complication rates.

A prospective randomized study with a 5-year minimum follow-up evaluation of transanal endoscopic microsurgery versus laparoscopic total mesorectal excision after neoadjuvant therapy.

BACKGROUND: This study aimed to compare the oncologic results for local excision via transanal endoscopic microsurgery (TEM) and those for laparoscopic resection (LR) via total mesorectal excision in the treatment of T(2) N(0), G(1-2 )rectal cancer after neoadjuvant therapy with both treatments, incorporating a 5-year minimum follow-up period. METHODS: The study enrolled 70 patients whose malignancy was staged at admission as T(2) N(0), G(1-2 )rectal cancer located within 6 cm of the anal verge with a tumor diameter less than 3 cm. Of these patients, 35 were randomized to TEM and 35 to LR. The patients in both groups previously had undergone high-dose radiotherapy (5,040 cGy in 28 fractions over 5 weeks) combined with continuous infusion of 5-flurouracil (200 mg/m(2)/day). RESULTS: The median follow-up period was 84 months (range, 72-96 months). Two local recurrences (5.7%) were observed after TEM and 1 (2.8%) after LR. Distant metastases (2.8%) occurred in one case each after TEM and LR. The probability of survival for rectal cancer was 94% for TEM and 94% for LR. CONCLUSIONS: The study shows similar results between the two treatments in terms of local recurrences, distant metastases, and probability of survival for rectal cancer.

Adrenal incidentaloma: surgical update.

Nowadays, the role of surgery in the treatment of adrenal incidentalomas (AI), considering their biologic behavior, is still debated. Surgery is mandatory in cases of hyperfunctioning adrenal masses, in the presence of suspect radiological malignancy, in cases of discordant computed tomography (CT) and scintigraphy findings and when the maximum diameter is 4 cm or more. On the other hand, studies have suggested relative inaccuracy of conventional CT in evaluating the size. The aim of this paper was to evaluate the safety and effectiveness of laparoscopic adrenalectomy (LA) in the treatment of AI by reviewing our experience. Over the period from 1995 to 2005 we laparoscopically managed 78 AI by anterior transperitoneal approach. Two LA (2.6%) were converted to open surgery. Neither intra- nor post-operative major complications were observed. The mean size of lesions was 5.5 cm (range 3-9). Twenty-one large adrenal lesions (exceeding 6 cm) were removed (27%). Definitive histology resulted as follows: adrenocortical adenoma (63), pheochromocytoma (5), nodular hyperplasia (4), myelolipoma (3), cysts (2), and adrenocortical carcinoma (1, with a size of 3 cm). The patients were followed-up by hormonal and radiological evaluation every 12 months (6 for malignancy); their follow-up (median 60.4 months, range 6-123) was uneventful. Also larger AI were treated safely. Laparoscopy has been safe and effective in the treatment of AI in our experience, according to specific literature.

Hepatic resections by means of electrothermal bipolar vessel device (EBVS) LigaSure V: early experience.

BACKGROUND: Many techniques and devices are available for performing liver resection, such as clamp crushing, Cavitron Ultrasonic Surgical Aspirator (CUSA), Hydrojet and dissecting sealer, ultrasonic shears, and, more recently, electrothermal bipolar vessel sealing system (EBVS). In this prospective trial we sought to evaluate the impact of EBVS on hepatic resections. METHODS: From March 2004 to December 2005, 24 patients from our consecutive liver resection series were enrolled in the present study. There were 17 males and 7 females with a mean age of 59.6 years (range = 41-80) who had colonic cancer metastases (18), hepatocarcinoma (3), angioma (2), and intrahepatic lithisasis (1). Patients were prospectively randomized to undergo liver resection via EBVS LigaSure V (12 patients, group A) or ultrasonic shears harmonic scalpel (HS) (12 patients, group B). Hepatic procedures did not differ significantly between the two groups and were as follows: right hepatectomy (2), left hepatectomy (1), bisegmentectomy (14), and segmentectomy (7). RESULTS: There was no mortality in either group. The mean operative time was 136.7 min (range = 90-210) in group A and 187.9 min (range = 130-360) in group B. The Pringle maneuver was done in five patients in group A [mean time = 11.4 min (range = 6-12)] and in four patients in group B [mean time = 16 min (range = 9-26)]. The mean blood loss, total bile salts, and hemoglobin concentration from drained fluid on the second postoperative day were 205.8 vs. 506.7 ml, 0.6 vs. 1.1 mmol/L, and 1.0 vs. 2.1 g/L (p < 0.05) for groups A and B, respectively. Mean postoperative hospital stay was 6.1 vs. 7.8 days. In group B a patient who underwent right hepatectomy for colon cancer metastases had transient hepatic failure. No patients received blood transfusions in group A, while two or more blood units were administered in two cases in group B. CONCLUSIONS: In the present study EBVS proved to be safe and effective for liver resection. By means of this device, statistically significant benefits concerning blood loss, total bile salts, and hemoglobin postoperative leakage were found.

Laparoscopic cecopexy for cecal volvulus after laparoscopy. Case report and a review of the literature.

Cecal volvulus is a rare cause of large bowel obstruction. Surgical therapy depends on visceral circulatory conditions at diagnosis. Possible options include endoscopic decompression, detorsion, cecopexy with or without cecostomy, right colectomy with immediate or delayed anastomosis. The present paper describes a case of cecal volvulus in a 40-year-old woman after laparoscopic removal of a pelvic mass successfully treated by laparoscopic cecopexy.

Thirteen years' experience with laparoscopic transcystic common bile duct exploration for stones. Effectiveness and long-term results.

BACKGROUND: The aim of the present study was to evaluate the effectiveness and long-term results of laparoscopic transcystic common bile duct exploration (TC-CBDE). METHODS: Ductal stones were present in 344 of 3212 patients (10.7%) who underwent laparoscopic cholecystectomy (LC). The procedure was completed laparoscopically in 329 patients (95.6%), with TC-CBDE performed in 191 patients (58.1%) who are the object of this study, or with a transverse choledochotomy in 138 cases (41.9%). RESULTS: Biliary drainage was employed in 71 of 191 cases (37.2%). Major complications occurred in 10 patients (5.1%), including retained stones in 6 (3.1%). Mortality was nil. No patients were lost to follow-up (median: 118.0 months; range: 17.6-168 months). No signs of bile stasis, no recurrent ductal stones and no biliary stricture were observed. At present 182 patients are alive with no biliary symptoms; 9 have died from unrelated causes. CONCLUSIONS: Long-term follow-up after laparoscopic TC-CBDE proved its effectiveness and safety for single-stage management of gallstones and common bile duct stones.

Laparoscopic radiofrequency renal ablation in patients with simultaneous visceral tumors: long-term follow-up.

PURPOSE: To report our experience with in situ laparoscopic radiofrequency ablation (RFA) of renal tumors. PATIENTS AND METHODS: From September 2000 to May 2002, two men, 81 and 71 years old, and one woman, 75 years old, were referred to our department for right renal clear-cell carcinoma <3.5-cm diameter. The 71- year-old patient had only one kidney. Because of the tumor location, the percutaneous route was not considered the approach of choice. Moreover, a simultaneous large right adrenal incidentaloma (myelolipoma) and a right colon cancer were known to be present in the second and third patient, respectively. The aforementioned findings suggested the laparoscopic route as a preferable technique to treat both the renal and the other morbidities. RESULTS: Under laparoscopic ultrasonography control of tine placement, a 20-minute thermoablation cycle at 100 degrees C mean temperature was performed. Including right colectomy and right adrenalectomy, the operative time was 120, 200, and 275 minutes, with postoperative hospital stays of 3, 4, and 6 days for the three patients, respectively. Abdominal CT scans after 1 and 4 weeks and then every 6 months confirmed complete treatment of the lesion at 44 months' average follow-up (range 36-56 months). CONCLUSION: When percutaneous access is not feasible or the patient should undergo another laparoscopic procedure simultaneously, laparoscopic RFA of renal tumors is feasible and effective, as shown by long-term follow-up.

Long-term results of laparoscopic versus open colorectal resections for cancer in 235 patients with a minimum follow-up of 5 years.

BACKGROUND: Laparoscopic resection for cure of colorectal cancer is controversial. More investigations on long-term results are required. This study aimed to compare the long-term outcome with a minimum follow-up of 5 years between laparoscopic or open approach for the treatment of colo-rectal cancer. METHODS: The treatment modality (laparoscopic or open) was related to the patients (pts) choice. The following parameters between the two groups (laparoscopic and open) were assessed: wound recurrences rate, local recurrences rate, incidence of distant metastases and survival probability analysis. RESULTS: We report the long term outcome of 149 pts with colon cancer of which 85 treated by Laparoscopic Surgery (LS) and 64 by Open Surgery (OS) and of 86 patients with rectal cancer of which 52 treated by LS and 34 by OS. In the pts with colonic cancer, mean follow-up was 82.8 months. No Statistically Significant Difference (SSD) was observed in the local recurrences rate (3.5% after LS and 6.2% after OS) and in the incidence of distant metastases (10.5% after LS and 10.9% after OS). Cumulative survival probability in LS was 0.882 as compared to 0.859 after OS. In the pts with rectal cancer, mean follow-up was 78.5 months. No SSD was observed in the local recurrences rate (19.2% after LS and 17.6% after OS) and in the incidence of distant metastases (15.3% after LS and 20.5% after OS). Cumulative survival probability in LS was 0.711 as compared to 0.617 after OS. We report an interesting data about the time of recurrences between LS and OS: the recurrences were delayed after LS, both after colonic (22.6 months vs 6.5) and rectal (25.7 months vs 13.0) resections, respectively. CONCLUSION: We suppose that laparoscopic surgery in the treatment of colo-rectal cancer is quite safe. However, further investigation is needed.

Long-term results in patients with T2-3 N0 distal rectal cancer undergoing radiotherapy before transanal endoscopic microsurgery.

BACKGROUND: Local excision after radiotherapy for node-negative low rectal cancer may be an alternative to radical excision. This study evaluated the results of local excision in patients with small (less than 3 cm in diameter) T2 and T3 distal rectal tumours following neoadjuvant therapy. METHODS: One hundred patients with rectal cancer (54 uT2 and 46 uT3 uN0 tumours) were enrolled. All patients underwent preoperative radiotherapy followed by local excision by means of transanal endoscopic microsurgery. RESULTS: Definitive histological examination revealed nine pT1, 54 pT2 and 19 pT3 tumours. A complete response (R0) or microscopic residual tumour (R1mic) was found in three and 15 patients respectively. Minor complications occurred in 11 patients and major complications in two. At a median follow-up of 55 (range 7-120) months, the local failure rate was 5 per cent and metastatic disease was found in two patients. The cancer-specific survival rate at 90 months' follow-up was 89 per cent, and the overall survival rate 72 per cent. Salvage abdominoperineal resection was performed in three patients, two of whom were disease free at 15 and 19 months. CONCLUSION: Treatment of small uT2 and uT3 uN0 rectal cancers with preoperative high-dose radiotherapy followed by transanal endoscopic microsurgery is an acceptable alternative to conventional radical resection.

Sub-mesocolic access in laparoscopic left adrenalectomy.

BACKGROUND: This article reports an alternative laparoscopic access to left adrenal gland. METHODS: From January 1994 to August 2004, 209 laparoscopic adrenalectomies were performed in our Department. Indications were Conn adenoma (55 cases), incidentaloma (64), Cushing adenoma (45), pheochromocytoma (32), adreno-genital syndrome (two), mielolipoma (two), and metastatic mass(nine). Of 209, in 12 cases the left adrenalectomy was performed through a submesocolic access (seven pheochromocytoma, two incidentaloma, two Cushing adenoma, one Conn adenoma,). The identification and closure of the adrenal vein with minimal gland manipulation resulted the main benefit of this approach. Moreover, the adrenalectomy was performed with minimal anatomical dissection. RESULTS: No mortality or major complications occurred. During the operation, the blood pressure and cardiac rhythm were significantly more stable, in the group of patients who underwent a left adrenalectomy by the submesocolic approach compared to the anterior or flank lateral transperitoneal group. CONCLUSIONS: Left adrenal lesions, as selected cases of pheochromocytoma, can be safely treated by laparoscopic submesocolic access.

Transanal endoscopic versus total mesorectal laparoscopic resections of T2-N0 low rectal cancers after neoadjuvant treatment: a prospective randomized trial with a 3-years minimum follow-up period.

BACKGROUND: This study aimed to compare the results and the oncologic outcomes of transanal endoscopic microsurgery (TEM) with neoadjuvant radiochemotherapy and laparoscopic resection (LR), also with neoadjuvant radiochemotherapy, in the treatment of T(2)-N(0) low rectal cancer. METHODS: The study enrolled 40 patients with T2-N(0) rectal cancer, randomizing 20 to TEM (arm A) and 20 to LR (arm B). RESULTS: After neoadjuvant radiochemotherapy, tumor downstaging was observed for 13 patients (65%) in arm A (7 pT0 and 6 pT1) and in 11 patients (55%) in arm B (7 pT0 and 4 pT1). More than a 50% reduction of the tumor diameter was observed in four arm A cases and in six arm B cases. At a median follow-up period of 56 months (range, 44-67 months) in both arms, one local failure (5%) occurred after 6 months in arm A and one (5%) after 48 months in arm B. Distant metastases occurred in one arm A patient (5%) after 26 months of follow-up evaluation and in one arm B patient (5%) at 31 months. The probability of local or distant failure was 10% for TEM and 12% for laparoscopic resection, whereas the probability of survival was 95% for TEM and 83% for laparoscopic resection. CONCLUSIONS: The findings show comparative results between the two study arms in terms of probability of failure and survival.

Long-term results after laparoscopic transverse choledochotomy for common bile duct stones.

BACKGROUND: The aim of this study was to evaluate the long-term results of laparoscopic transverse choledochotomy (TC) during laparoscopic cholecystectomy (LC). METHODS: Ductal stones were present in 344 of 3,212 patients (10.7%) who underwent LC. The procedure was completed laparoscopically in 329 cases (95.6%), with a TC in 138 cases (41.9%) (the subjects of this study), and with a transcystic duct approach in 191 cases (58.1%). RESULTS: Biliary drainage was used in 131 of 138 cases (94.9%). There were major complications in eight patients (5.7%), and one patient died (0.7%). Retained stones were seen in 11 cases (8%). None of the patients was lost to follow-up (mean, 72.3 months; range, 11-145). Ductal stones recurred in five patients (3.6%). No signs of bile stasis and no biliary strictures were observed. In all, 121 patients are alive with no biliary symptoms; 16 have died from unrelated causes. CONCLUSION: Long-term follow-up after laparoscopic TC during LC proved its safety and efficacy.

Laparoscopic colorectal resection for endometriosis.

BACKGROUND: The rectosigmoid colon is affected by deep pelvic endometriosis in 3-37% of cases. In the past, treatment of the affected gastrointestinal tract generally required conversion to conventional surgery. We describe our experience with complete laparoscopic management of deep pelvic endometriosis with bowel involvement. METHODS: From March 1995 to March 2003, 29 consecutive patients with endometriosis requiring laparoscopic intervention were evaluated. In seven patients (24%) colorectal involvement was identified prior to the operation. A low anterior resection was performed in four patients (57%) and a sigmoid resection in three (43%). In all cases, colonoscopy showed a normal mucosa. In all cases, treatment consisted of resection of the bowel involved together with the excision of all other implants. Data analysis included age, previous abdominal operations, previous history of endometriosis, operative time, conversion rate, complications, length of stay, and pain relief. RESULTS: There were seven patients with colorectal involvement whose median age was 32.8 years (range, 28-40), with a history of previous abdominal operation in two (28%). Preoperative symptoms were as follow: dysmenorrea in four patients (57%), dyspareunia in four (57%), pelvic pain in seven (100%), rectal bleeding in one (14%), and tenesmus in five (71%). Mean operative time was 190 min (range, 165-230). Length of stay was 8.3 days (range, 7-11). There were no anastomotic leak and no major postoperative complication. One patient had temporary urinary retention. At a median follow-up of 38.7 months (range, 1-84), complete relief of pelvic symptoms was achieved in five patients (71%), and there was improvement in one patient. In one patient complaining of persistent pain, a new colonic implant was diagnosed two years after the surgery requiring reoperation. CONCLUSIONS: The results show that provided that the surgeon is highly skilled in laparoscopy, laparoscopic resection of deep pelvic endometriosis with rectosigmoid involvement is feasible and effective in nearly all patients.

Closure of tracheo-oesophageal fistula following removal of voice prosthesis; a new surgical technique.

The voice prosthesis is today the most widely used and accepted method of voice restoration following total laryngectomy. Fortunately, the cases in which it is necessary to temporarily or definitively close the fistula are rare (request of the patient, leakage from the fistula, aspiration pneumonia). Herein, an analysis is made of these cases and the surgical technique personally developed for the closure of tracheo-oesophageal fistula is described. This technique has been used in 8 patients with good results; moreover, it is a relatively low cost procedure and gives rise to few post-operative complications.

Laparoscopic versus open hemicolectomy.

AIM: In the last decade, laparoscopic procedures are applied to the treatment of almost all colonic diseases, including both benign and malignant lesions. Focusing our attention to the laparoscopic operative technique, we compare the perioperative results and the oncological outcomes of laparoscopic hemicolectomy with those after open conventional hemicolectomy. METHODS: This prospective non randomized study is based on a series of 469 consecutive patients (73.6% with malignant lesions) operated on by the same surgical team following the same type of surgical technique, for laparoscopic and open approach, to perform right (RH) and left (LH) hemicolectomy, respectively, excluding segmental resections, emergency operations as well as transverse colon, splenic flexure and recurrent carcinomas. The treatment modality was selected by the patients after reading the informed consent form. Conversion rate to open surgery (for the laparoscopic group) and causes were assessed. Statistical significance (p) for operative time, resumption of gastrointestinal functions, length of stay, complications, perioperative mortality, as well as length of specimen, number of lymph-nodes harvest, incidence of local recurrences and distant metastases, and survival probability analysis in malignant cases, was assessed between the 2 groups (laparoscopic and open). RESULTS: From March 1992 to February 2003, 166 patients underwent RH and 303 LH. In the RH group, 108 patients underwent laparoscopic approach and 58 underwent open surgery (26 vs 13 for benign lesions and 82 vs 45 for adenocarcinomas, respectively). LH was performed by laparoscopy in 202 patients and by laparotomy in 101 (55 vs 30 for benign lesions and 147 vs 71 for adenocarcinomas, respectively). There were no conversions to open surgery in laparoscopic RH, while 10 patients (4.9%) in the laparoscopic LH group required conversion: 3 of 34 performed for diverticular disease and 7 of 147 performed for malignancy. Mean operative time for laparoscopic surgery was longer than for open surgery (182 vs 140 min for RH and 222 vs 190 min for LH, respectively), but with increasing experience this decreased significantly. Mean hospital stay in patients who underwent laparoscopic procedures was significantly shorter both in RH and LH groups (9.2 vs 13.2 days and 9.9 vs 13.2 days, respectively). Similar major complication rates were observed between the 2 laparoscopic and open groups (1.8% vs 1.7% for RH and 4.1% vs 4.9% for LH, respectively). Follow-up time ranged between 12 and 109 months (mean, 57.3 months) in RH groups and between 12 and 111 months (mean, 57.5 months) in LH groups. The follow-up dropout was of only 3 patients after RH (in the laparoscopic group) and 5 after LH (3 in the laparoscopic group and 2 in the open group). The local recurrence rate was lower after laparoscopic surgery in both arms (7% vs 8.8% for RH and 3.3% vs 7% for LH, respectively), but the differences were not statistically significant. Two port site recurrences were observed in the laparoscopic groups, 1 after a Dukes D palliative RH and 1 after a Dukes C LH converted to open surgery (1.7% and 0.9%, respectively). Metachronous metastases rates were similar between the laparoscopic and open groups (20.9% vs 17.6% for RH and 4.4% vs 5.3% for LH, respectively). Cumulative survival probability (CSP) at 72 months after laparoscopic RH was 0.791 as compared to 0.765 after open surgery (p=0.326) and 0.956 after laparoscopic LH as compared to 0.877 after open surgery (p=0.115). CSP for Dukes stage A, B and C in the laparoscopic RH group was 0.875, 0.846, and 0.727 as compared to 0.9 (p=0.815), 0.889 (p=0.87), and 0.6 (p=0.183) after open surgery, respectively. CSP for Dukes stage A, B and C in the laparoscopic LH group was 0.1, 0.966, and 0.885 as compared to 0.1 (p=0.936), 0.944 (p=0.466), and 0.7 (p=0.072) after open surgery, respectively. CONCLUSION: These results suggest that laparoscopic hemicolectomy for both benign and malignant lesions can be performed safely. Oncological outcomes were comparable with those of open surgery.