Inter-fractional monitoring of [Formula: see text]C ions treatments: results from a clinical trial at the CNAO facility.

The high dose conformity and healthy tissue sparing achievable in Particle Therapy when using C ions calls for safety factors in treatment planning, to prevent the tumor under-dosage related to the possible occurrence of inter-fractional morphological changes during a treatment. This limitation could be overcome by a range monitor, still missing in clinical routine, capable of providing on-line feedback. The Dose Profiler (DP) is a detector developed within the INnovative Solution for In-beam Dosimetry in hadronthErapy (INSIDE) collaboration for the monitoring of carbon ion treatments at the CNAO facility (Centro Nazionale di Adroterapia Oncologica) exploiting the detection of charged secondary fragments that escape from the patient. The DP capability to detect inter-fractional changes is demonstrated by comparing the obtained fragment emission maps in different fractions of the treatments enrolled in the first ever clinical trial of such a monitoring system, performed at CNAO. The case of a CNAO patient that underwent a significant morphological change is presented in detail, focusing on the implications that can be drawn for the achievable inter-fractional monitoring DP sensitivity in real clinical conditions. The results have been cross-checked against a simulation study.

Particle beam microstructure reconstruction and coincidence discrimination in PET monitoring for hadron therapy.

Positron emission tomography is one of the most mature techniques for monitoring the particles range in hadron therapy, aiming to reduce treatment uncertainties and therefore the extent of safety margins in the treatment plan. In-beam PET monitoring has been already performed using inter-spill and post-irradiation data, i.e. while the particle beam is off or paused. The full beam acquisition procedure is commonly discarded because the particle spills abruptly increase the random coincidence rates and therefore the image noise. This is because random coincidences cannot be separated by annihilation photons originating from radioactive decays and cannot be corrected with standard random coincidence techniques due to the time correlation of the beam-induced background with the ion beam microstructure. The aim of this paper is to provide a new method to recover in-spill data to improve the images obtained with full-beam PET acquisitions. This is done by estimating the temporal microstructure of the beam and thus selecting input PET events that are less likely to be random ones. The PET detector we used was the one developed within the INSIDE project and tested at the CNAO synchrotron-based facility. The data were taken on a PMMA phantom irradiated with 72 MeV proton pencil beams. The obtained results confirm the possibility of improving the acquired PET data without any external signal coming from the synchrotron or ad hoc detectors.

Monte Carlo simulation tool for online treatment monitoring in hadrontherapy with in-beam PET: A patient study.

Hadrontherapy is a method for treating cancer with very targeted dose distributions and enhanced radiobiological effects. To fully exploit these advantages, in vivo range monitoring systems are required. These devices measure, preferably during the treatment, the secondary radiation generated by the beam-tissue interactions. However, since correlation of the secondary radiation distribution with the dose is not straightforward, Monte Carlo (MC) simulations are very important for treatment quality assessment. The INSIDE project constructed an in-beam PET scanner to detect signals generated by the positron-emitting isotopes resulting from projectile-target fragmentation. In addition, a FLUKA-based simulation tool was developed to predict the corresponding reference PET images using a detailed scanner model. The INSIDE in-beam PET was used to monitor two consecutive proton treatment sessions on a patient at the Italian Center for Oncological Hadrontherapy (CNAO). The reconstructed PET images were updated every 10 s providing a near real-time quality assessment. By half-way through the treatment, the statistics of the measured PET images were already significant enough to be compared with the simulations with average differences in the activity range less than 2.5 mm along the beam direction. Without taking into account any preferential direction, differences within 1 mm were found. In this paper, the INSIDE MC simulation tool is described and the results of the first in vivo agreement evaluation are reported. These results have justified a clinical trial, in which the MC simulation tool will be used on a daily basis to study the compliance tolerances between the measured and simulated PET images.

Full-beam performances of a PET detector with synchrotron therapeutic proton beams.

Treatment quality assessment is a crucial feature for both present and next-generation ion therapy facilities. Several approaches are being explored, based on prompt radiation emission or on PET signals by [Formula: see text]-decaying isotopes generated by beam interactions with the body. In-beam PET monitoring at synchrotron-based ion therapy facilities has already been performed, either based on inter-spill data only, to avoid the influence of the prompt radiation, or including both in-spill and inter-spill data. However, the PET images either suffer of poor statistics (inter-spill) or are more influenced by the background induced by prompt radiation (in-spill). Both those problems are expected to worsen for accelerators with improved duty cycle where the inter-spill interval is reduced to shorten the treatment time. With the aim of assessing the detector performance and developing techniques for background reduction, a test of an in-beam PET detector prototype was performed at the CNAO synchrotron-based ion therapy facility in full-beam acquisition modality. Data taken with proton beams impinging on PMMA phantoms showed the system acquisition capability and the resulting activity distribution, separately reconstructed for the in-spill and the inter-spill data. The coincidence time resolution for in-spill and inter-spill data shows a good agreement, with a slight deterioration during the spill. The data selection technique allows the identification and rejection of most of the background originated during the beam delivery. The activity range difference between two different proton beam energies (68 and 72 MeV) was measured and found to be in sub-millimeter agreement with the expected result. However, a slightly longer (2 mm) absolute profile length is obtained for in-spill data when compared to inter-spill data.

[Rubber band ligation in treatment of hemorrhoids: our experience]. / Legatura elastica delle emorroidi: nostra esperienza.

OBJECTIVES: Hemorrhoids are a very common condition. The treatment depends upon persistence and severity of symptoms. For hemorrhoids of II and III grade the rubber band ligation may be therapeutic. Our aim is to report the outcomes of rubber band ligation of hemorrhoids, with a follow up of 6 months. MATERIALS AND METHODS: A total of 50 patients underwent rubber band ligation for symptomatic hemorrhoids (grade II and III) without prolapse, between June 2012 and June 2014. All patients underwent plug test to rule out presence of rectal mucosal prolapse and were classified according to PATE classification (1). Each hemorrhoid was ligated with one rubber band through a ligator. All patients were evaluated immediately at the end of the procedure, after ten days and six months after the treatment. Patient's demographic and operative data were collected and analyzed. RESULTS: The mean patients age was 47.6±12.3 years (range 24-72). All procedures were performed without complications. Before rubber band ligation, 42 patients had rectal bleeding, 38 had perineal discomfort and 27 had itching. Ten days after the treatment, 12 patients presented self-limited rectal bleeding, but 10 of these had more hemorrhoids and underwent a second rubber band ligation. No patients complained perineal discomfort, and 8 patients had itching; 78% and 16% of patients respectively, experienced feeling of a foreign body inside the canal anal and anal pain. After 6 months, only 13 patients were occasionally symptomatic: 4 patients had rectal bleeding, 2 had perineal discomfort and 4 had itching. Three more patients presented both perineal discomfort and hitching. None had the feeling of a foreign body in anal canal or anal pain. CONCLUSIONS: Rubber band ligation is an efficacious, cost-effective and simple treatment for the second and third degree hemorrhoids without rectal mucosal prolapsed. In our hands, no severe complications developed and minor complications could be handled with ease.

Proton range monitoring with in-beam PET: Monte Carlo activity predictions and comparison with cyclotron data.

GOAL: Proton treatment monitoring with Positron-Emission-Tomography (PET) is based on comparing measured and Monte Carlo (MC) predicted ß(+) activity distributions. Here we present PET ß(+) activity data and MC predictions both during and after proton irradiation of homogeneous PMMA targets, where protons were extracted from a cyclotron. METHODS AND MATERIALS: PMMA phantoms were irradiated with 62 MeV protons extracted from the CATANA cyclotron. PET activity data were acquired with a 10 × 10 cm(2) planar PET system and compared with predictions from the FLUKA MC generator. We investigated which isotopes are produced and decay during irradiation, and compared them to the situation after irradiation. For various irradiation conditions we compared one-dimensional activity distributions of MC and data, focussing on Δw50%, i.e., the distance between the 50% rise and 50% fall-off position. RESULTS: The PET system is able to acquire data during and after cyclotron irradiation. For PMMA phantoms the difference between the FLUKA MC prediction and our data in Δw50% is less than 1 mm. The ratio of PET activity events during and after irradiation is about 1 in both data and FLUKA, when equal time-frames are considered. Some differences are observed in profile shape. CONCLUSION: We found a good agreement in Δw50% and in the ratio between beam-on and beam-off activity between the PET data and the FLUKA MC predictions in all irradiation conditions.

First full-beam PET acquisitions in proton therapy with a modular dual-head dedicated system.

During particle therapy irradiation, positron emitters with half-lives ranging from 2 to 20 min are generated from nuclear processes. The half-lives are such that it is possible either to detect the positron signal in the treatment room using an in-beam positron emission tomography (PET) system, right after the irradiation, or to quickly transfer the patient to a close PET/CT scanner. Since the activity distribution is spatially correlated with the dose, it is possible to use PET imaging as an indirect method to assure the quality of the dose delivery. In this work, we present a new dedicated PET system able to operate in-beam. The PET apparatus consists in two 10 cm × 10 cm detector heads. Each detector is composed of four scintillating matrices of 23 × 23 LYSO crystals. The crystal size is 1.9 mm × 1.9 mm × 16 mm. Each scintillation matrix is read out independently with a modularized acquisition system. The distance between the two opposing detector heads was set to 20 cm. The system has very low dead time per detector area and a 3 ns coincidence window, which is capable to sustain high single count rates and to keep the random counts relatively low. This allows a new full-beam monitoring modality that includes data acquisition also while the beam is on. The PET system was tested during the irradiation at the CATANA (INFN, Catania, Italy) cyclotron-based proton therapy facility. Four acquisitions with different doses and dose rates were analysed. In all cases the random to total coincidences ratio was equal or less than 25%. For each measurement we estimated the accuracy and precision of the activity range on a set of voxel lines within an irradiated PMMA phantom. Results show that the inclusion of data acquired during the irradiation, referred to as beam-on data, improves both the precision and accuracy of the range measurement with respect to data acquired only after irradiation. Beam-on data alone are enough to give precisions better than 1 mm when at least 5 Gy are delivered.

Massively parallelizable list-mode reconstruction using a Monte Carlo-based elliptical Gaussian model.

PURPOSE: A fully three-dimensional (3D) massively parallelizable list-mode ordered-subsets expectation-maximization (LM-OSEM) reconstruction algorithm has been developed for high-resolution PET cameras. System response probabilities are calculated online from a set of parameters derived from Monte Carlo simulations. The shape of a system response for a given line of response (LOR) has been shown to be asymmetrical around the LOR. This work has been focused on the development of efficient region-search techniques to sample the system response probabilities, which are suitable for asymmetric kernel models, including elliptical Gaussian models that allow for high accuracy and high parallelization efficiency. The novel region-search scheme using variable kernel models is applied in the proposed PET reconstruction algorithm. METHODS: A novel region-search technique has been used to sample the probability density function in correspondence with a small dynamic subset of the field of view that constitutes the region of response (ROR). The ROR is identified around the LOR by searching for any voxel within a dynamically calculated contour. The contour condition is currently defined as a fixed threshold over the posterior probability, and arbitrary kernel models can be applied using a numerical approach. The processing of the LORs is distributed in batches among the available computing devices, then, individual LORs are processed within different processing units. In this way, both multicore and multiple many-core processing units can be efficiently exploited. Tests have been conducted with probability models that take into account the noncolinearity, positron range, and crystal penetration effects, that produced tubes of response with varying elliptical sections whose axes were a function of the crystal's thickness and angle of incidence of the given LOR. The algorithm treats the probability model as a 3D scalar field defined within a reference system aligned with the ideal LOR. RESULTS: This new technique provides superior image quality in terms of signal-to-noise ratio as compared with the histogram-mode method based on precomputed system matrices available for a commercial small animal scanner. Reconstruction times can be kept low with the use of multicore, many-core architectures, including multiple graphic processing units. CONCLUSIONS: A highly parallelizable LM reconstruction method has been proposed based on Monte Carlo simulations and new parallelization techniques aimed at improving the reconstruction speed and the image signal-to-noise of a given OSEM algorithm. The method has been validated using simulated and real phantoms. A special advantage of the new method is the possibility of defining dynamically the cut-off threshold over the calculated probabilities thus allowing for a direct control on the trade-off between speed and quality during the reconstruction.

[Mucoprolassectomy with circular stapler: early results with a new device]. / Mucoprolassectomia con suturatrice circolare: utilizzo di un nuovo device.

AIMS: Stapled transanal mucosectomy is widely used by a lot of surgeon and in RCT, when compared to other haemorrhoidectomy techniques, it didn't show a real primacy. We describe results obtained with a new device, the EEA™ 33-mm Hemorrhoid and Prolapse Stapler Set con DST Series™ (Covidien™), used on 65 patients. PATIENTS AND METHODS: Sixty-five patients underwent a stapled transanal mucosectomy for grade III (n° 20), IV (n° 15) haemorrhois and rectal prolapse (n° 30). The operation were performed by two surgeons. Results. Resected tissue had a mean width of 4.2 cm (3.3-6.1 cm) and a mean weight of 11 g (8-21 g). Surgical time were 22 min (15-35 min). Bleeding of the suture line were observed in 5 cases (7.7%) and they required a mean of 2 haemostatic stitch (1-5) in adsorbable suture 2/0. Mucoprolapsectomy was considered excellent in 55 patients (84.7%), good in 8 patients (12.3%), bad in 2 patients (3%) by surgeons. There were no early and late complications like bleeding, abscesses, anastomotic dehiscence. We report two case of perianal haematoma that don't need any treatment and one case of anal stenosis treated with dilatation therapy. Post-operative pain, estimated with VAS, emphasized an excellent response to NSAIDs in first postoperative day, in 10 cases (15.4%) we prolonged analgesic therapy for 3 days, in one case (1.5%) for one week. After 6 month all patients were revaluated with physical examination and anoscopy. Only one patient (1.5%) had an asymptomatic recurrence of rectal prolapse. CONCLUSION: We conclude that the new device makes easy and standardized surgery. The new device reduce a lot of difficult in patients with tight pelvis and a small distance between ischiatic tubers.

Stapled hemorrhoidopexy in the treatment of hemorrhoid disease. Our eight-year experience.

AIM: Stapled hemorrohoidopexy using Longo technique (PPH) is accompanied by good postoperative outcomes. The aim of this study was to report the data regarding our experience with stapled hemorrhoidopexy, the results of the operations and the complications rate in comparison with those published in the literature. METHODS: In our Department 127 patients with symptomatic hemorrhoids have been selected between November 2000 and December 2008 for PPH. This retrospective study included patients with a rectal prolapse from second to fourth degree. RESULTS: Two patients had an anal bleeding on the day of surgery. All of them were returned to the operating theatre. A third patient had an anal bleeding that did not require a second surgical intervention. In one case a postoperative stenosis occurred that required a reoperation three days after the dismission from hospital. In one case an urgency occurred, with transitional fecal incontinence, spontaneously regressed two weeks after the intervention. No urinary retention occurred in our caseload. Pain was referred by 37 patients and was controlled by standard analgesia in all cases. No cases of chronic pain were detected. There were no cases of anal stenosis, permanent incontinence or deaths in this series. CONCLUSION: Among the cases examined important complications occurred in five (3.9%), but reintervention was necessary only for three patients (2.4%). This study confirms that PPH, used on patients with a rectal prolapse from second to fourth degree, is feasible and safe.

[Proctological surgery: use of a salsobromoiodic gel solution in the post-operative period]. / Chirurgia proctologica: uso di una soluzione salsobromoiodica in gel nel post-operatorio.

BACKGROUND: This study was aimed to demonstrate the advantages and the efficacy of a salsobromoiodic gel solution sponge to use in coloproctology after surgery for the most frequent pathologies of anal canal and of perineal region. MATERIALS AND METHODS: The Authors have tested the salsobromoiodic gel solution (Fertomcidina U) in a consecutive series of patients referred to 5 coloproctological centers where they have been submitted to surgery for pathologies of anal canal and of perineal region. A total of 30 patients, 15 with clinico-instrumental diagnosis of III-IV degree haemorrhoids and 15 with diagnosis of chronic anal fissure entered in a clinical follow-up after an out-patient setting or surgery for the respective pathologies. The gel formulation is realized as a salsobromoiodic solution containing salicylic acid and magnesium biphosphate making a strong bactericide and fungicide action applicable on human skin for tissues reparation and their re-epithelization. The experimental treatment was performed on the duration of at least 10 days, with two topic applications. RESULT: In 100% of the treated patients, the used gel has determined the prevention of infective complications, favouring a normal re-epithelization of tissue submitted to surgery or affected by previous anal mucosal lesions. The use of gel has not caused irritation and skin damage. No symptom and sign of toxicity were observed. CONCLUSIONS: The use of salsobromoiodic gel solution has been useful to prevent infections and to contribute to the cicatrisation, healing and re-epithelization of anal mucosal lesions after surgery on a normal outpatients setting. The use of gel formulation resulted easy and satisfactory for the patients affected by the most frequent proctological pathologies which require a surgical treatment.

Palliative treatment of upper gastrointestinal obstruction using self-expansible metal stents.

Gastric outlet obstruction is either a late event in the natural history of bilio-pancreatic tumors or the result of recurrent gastric or pancreatic tumors. Self-expansible metal stents, inserted under endoscopic and fluoroscopic control, can be used for palliative treatment. The present study was aimed at evaluating both the feasibility and the results of stenting in patients with malignant gastric outlet obstruction; in addition, some technical suggestions are presented. A total of 33 patients, who had a metal stent positioned, were retrospectively evaluated; 20 of them were women and 13 were men, aged from 45 to 94 years, with a mean age of 75 years. Twenty-seven patients had a pancreatic adenocarcinoma, 4 had a stricture of a gastrojejunal anastomosis due to recurrent pancreatic tumor, 2 had a stricture of a gastrojejunal anastomosis secondary to gastric cancer surgery. No postoperatory complications were observed. Improvement in the quality of life was obtained in all patients. Following the stenting procedure, the median duration of hospitalization was 8 days (range: 6-20 days), and the mean survival rate was 12 weeks (range: 2-66 weeks). Endoscopic stenting for the palliation of malignant gastric outlet obstruction is feasible and is well tolerated by most patients. In some cases a period of enteral nutrition had to be necessarily carried out; nonetheless, the insertion of the stent improved the quality of life.

Giant mesenteric fibromatosis.

Mesenteric fibromatosis is a proliferative fibroblastic neoplasia of the small intestine mesentery which may occur as a unique or multiple formation. Mesenteric fibromatosis represents the 8% of all desmoid neoplasm. Giant mesenteric fibromatosis is uncommon by itself (2-4 case/milion/year). Since the rarity of this tumor and the difficulties in diagnostic and therapeutic ambit, we believe it justified to describe a case of giant mesenteric fibromatosis which came to our observation.

Palliative treatment for malignant jaundice: endoscopic vs surgical approach.

In this retrospective, comparative study a total of 107 patients, presenting with malignant inoperable strictures of common bile duct, due to a pancreatico-biliary malignancy, underwent palliative treatments. In a group, consisting of 82 patients (76.64%), endoscopic stenting procedures were performed; polyethylene stents or self-expanding metal stents were applied in 37 and 45 patients, respectively. The prerequisites for a successful endoscopic stenting were a) accuracy of diagnosis and b) exclusion of patients presenting with tumors potentially treatable by a curative resection. In the other group, consisting of 25 patients (23.36%), biliary-enteric bypass procedures were performed. Endoscopic treatment was successful in 97.5% of the cases (80/82); complication rate was 7.3% (6 patients on 82), and mortality rate was 3.6% (3 patients on 82). Median hospital stay was 13.4 and 7.3 days in patients treated with plastic stents and metallic stents, respectively. Bypass surgery was successful in 99% of the cases (24/25); complication rate was 24% (6 patients on 25), and mortality rate was 16% (4 patients on 25). Median hospital stay was 26 days. For the patients in whom a curative resection could not be performed, both the above mentioned methods resulted in a high rate of immediate technical and therapeutic success. However, the surgical approach showed a significantly higher rate in procedure-related mortality and morbidity; in addition, the hospital stay lasted longer in surgically treated patients. The patients who are definitely unsuitable for curative resection are better managed by positioning a stent. The use of metal stents should be preferred in those less serious patients who may supposedly survive longer.

ERCP and acute pancreatitis.

Acute biliary pancreatitis (ABP) is a serious complication of biliary stones disease and is associated with significant morbidity and mortality. The role of ERCP in the management of ABP has been the focus of discussion in recent years. In this report, we evaluated a protocol of emergency Endoscopic retrograde Cholangiopancreatography (ERCP) (within 24 hours) and early ERCP (within 72 hours). From July 1997 to July 2000, were observed 45 patients (19 man and 26 women) with acute biliary pancreatitis. Mean age of patients was 63.4 years (range 21-87 years). Diagnosis of ABP was based on anamnesis and clinical assessment and was confirmed by specific laboratory data (hyperamylasemia, hyperlipasemia, total and fractionated bilirubinemia, gamma-GT, transaminase, alkaline phosphatase, hypocalcemia, hyperglycemia, leukocytosis). Ultrasound scanning within 24 h of admission was performed in 45 patients (100%) and it revealed gallbladder stones and muddy bile in 39 patients (87%). Computed tomography (CT) performed in all patients, showed a severe acute pancreatitis in the second or subsequent week following admission. The severity of acute pancreatitis was established by Glasgow's criteria and by clinical details of patients. ERCP and Endoscopic Sphinterotomy (ES) was performed in all 45 patients with acute biliary pancreatitis. Twenty-six patients (57%) were classified as having a severe attack (> 4) 19 as having a mild attack by Glasgow's criteria. ERCP associated with ES was performed within 24 hours in 22 patients (49%), 11 (50%) showed a severe attack and 11 (50%) showed a mild attack. A total of 2 complications (4%) occurred and the mortality was of 2 patients (4%). In 23 patients (51%) ERCP and ES was performed within 72 hours after conservative therapy, 8 (35%) showed a mild attack and 15 (65%) showed a severe attack. A total of 5 complications (9%) occurred and the mortality was of 3 patients (6%). Our study showed that ERCP with endoscopic sphincterotomy can be performed safely by skilled endoscopist, without adverse consequences soon after the onset of acute biliary pancreatitis even within the first 24 hours and it showed that is better than ERCP within 72 hours after conservative therapy.

Rapidly destructive bilateral hip disease: a case report and review of the literature.

We describe the case of an elderly woman with rapid destruction of the right hip followed by the same involvement of her left hip 10 months later. The clinical history, the physical examination and radiographic images suggested the diagnosis of rapidly destructive hip disease. This disease is a distinct entity, unilateral in 80%-90% of cases, which requires extensive investigation and special efforts for its identification. Essential elements for the differential diagnosis are discussed.

Sentinel node role in breast cancer surgery.

Radical surgery of breast cancer includes lymphadenectomy of axilla as well as the dissection of the neoplastic tissue. However recently many works have raised doubts on the opportunity of performing routinary axillary dissection, which elevates morbidity risk, in absence of axillary metastases. However, unfortunately, information on axillary lymph node pathology, is not available with any other technique excluding complete dissection and istopathological examination. Sentinel node technique is a new methodology that consents evaluation of lymph node status in the operating theatre. It allows the surgeon to judge on the opportunity of carrying out the lymphadenectomy or not.

Conservative approach in the treatment of the biliary tract's iatrogenic lesions.

Iatrogenic lesions of the biliary tract have always represented a problem of real actuality in the abdominal surgery. The incidence of post-cholecystectomy complications is from 0.1% to 0.25% and it's increased to 0.3-0.6% for laparoscopic surgery. Potential predisposing factors to iatrogenic biliary lesions are anatomic anomalies, acute and chronic phlogosis and technical mistakes. Anatomic anomalies are present in 6-25% of all cases according to different statistics; an incomplete knowledge of the biliary tract can predispose to a mistake legating or dissecting a wrong branch. This paper present a caseload of 27 patients admitted to our Service of Digestive Endoscopy owing to post laparoscopic cholecystectomy complications. Patients have been recruited in a period from two days to six months to the intervention. Detected complicances have been divided in "major", which comprehended biliary lesions (7 cases) and biliary stenosis (8 cases), and in "minor" which included biliary leakages (12 cases). CPRE, PTC, Ultrasound, CT and cholangio-MR were used to diagnose the biliary damage. Conservative approach has been resolutive in all patients with minor biliary lesions and in three cases of major lesions; in seven cases of biliary stenosis endoscopic-radiologic combined treatment has been successfully performed, in the other patients surgical operation was obliged choice. Comparing our results with literature we can affirm that conservative treatment represents the first choice in case of minor lesions (100% of successes), whereas in case of major biliary lesions it constitutes a valid alternative to the reparative surgery; when surgical option results impossible to defer, it can help the surgeon identifying the damage and draining the biliary tract.

Central venous catheter disruption and embolization: percutaneous retrieval. A case report.

Disruption followed by intravasal embolization is a rare (0.5%) however possible complication secondary to the insertion of a central venous catheter. The carriers of these implantable systems are patients who, for their cure and at times even for their survival, require the chronic intravenous infusion of drugs and solutions. Therefore materials that can allow long-term insertion with a minimum of complications are the most suitable. There are several causes of disruption and embolization of cannulae. The most common are represented by the pinch-off syndrome and catheter disconnection from reservoir. The literature on the subject is illustrated and a personal case treated with intravascular retrieval is reported.

A multidisciplinary approach to the treatment of small-cell lung cancer: the role played by surgery.

The authors report their data on 344 cases of small-cell lung cancer treated according to indications with combined chemoradiotherapy and in selected cases with surgical intervention. In patients with limited disease, the results of pharmacologic therapy significantly improve the prognosis only in association with surgery. The role of surgery has been reappraised in the treatment of small-cell lung cancer which appears, nowadays, multidisciplinary.