Endoscopic ultrasound-guided fine-needle aspiration for the diagnosis of extra-pulmonary tuberculosis.

SETTING: The incidence of extra-pulmonary tuberculosis (EPTB) is surprisingly high among certain subgroups of patients in industrialized countries. Diagnosis is often difficult and can require costly invasive workup. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe, minimally invasive, accurate, out-patient diagnostic modality for assessing mediastinal and abdominal lymphadenopathy and masses. OBJECTIVE: To evaluate the usefulness of EUS-FNA for diagnosing EPTB. DESIGN: Retrospective 6-year review, including all patients who had evidence of lymphadenopathy or mass on computed tomography scan accessible by EUS and consideration of tuberculosis (TB) in the differential diagnosis. RESULTS: Of 81 potential patients, a total of 20 cases with EPTB diagnosed by EUS-FNA were identified. Necrotizing granulomas had a 58% likelihood of TB vs. 14% for other cytologic findings (P < 0.0001); necrosis was also predictive, with a 44% likelihood of TB vs. 19% (P < 0.0225). EUS-FNA cytology was diagnostic for TB when an African-born patient had necrotizing granulomas (P < 0.0001), and was highly suggestive with necrosis alone (P < 0.0514). Non-necrotizing granulomas were not predictive of TB and an alternative diagnosis was more likely, including sarcoidosis and cancer. CONCLUSION: EUS-FNA is a useful diagnostic modality that should be used early in the diagnostic workup of suspected EPTB.

Endoscopic ultrasound rendezvous for bile duct access using a transduodenal approach: cumulative experience at a single center. A case series.

Endoscopic ultrasound (EUS)-assisted biliary access is utilized when conventional endoscopic retrograde cholangiopancreatography (ERCP) fails. We report a 10-year experience utilizing a transduodenal EUS rendezvous via a transpapillary route without dilation of the transduodenal tract, followed by immediate ERCP access. Patients included all EUS-guided rendezvous procedures for biliary access that were performed following ERCP failure. EUS-assisted bile duct puncture was performed via a transduodenal approach and a guide wire was advanced through the papilla without any dilation or bougienage of the tract; ERCP was performed immediately afterwards. EUS-assisted biliary rendezvous was attempted in 15 patients (mean age 66 +/- 18.2 years; malignant = 10, benign = 5). Mean diameter of measured bile ducts was 14.3 +/- 5.17 mm (range 4-23 mm). The reasons for initial ERCP failure were tumor infiltration or edema (n = 9), intradiverticular papilla (n = 2), pre-existing duodenal stent (n = 1), and anatomic anomalies (n = 3). Successful EUS-guided bile duct puncture and wire passage were achieved in all 15 patients (100 %), with drainage being successful in 12 / 15 (80 %). Failures occurred in three patients due to inability to traverse the biliary stricture (n = 2) or dissection of a choledochocele with the guide wire (n = 1); all were subsequently drained via percutaneous methods. Stents placed were metallic in eight patients and plastic in four. Complications consisted of moderate pancreatitis after a difficult ERCP attempt in one patient, and bacteremia after percutaneous biliary drainage in another. There were no instances of perforation, extraluminal air or fluid collections. EUS-assisted biliary drainage utilizing a transduodenal rendezvous approach demonstated a high success rate without any complications directly attributable to the EUS access. Advantages over percutaneous biliary and other methods of EUS biliary access include performance under the same anesthesia, and a very small-caliber needle puncture similar to EUS/fine-needle aspiration.

Endoscopic ultrasound-guided pancreatic duct aspiration: diagnostic yield and safety.

BACKGROUND AND STUDY AIMS: Endoscopic ultrasound (EUS)-guided fine-needle aspiration provides useful diagnostic material in solid and cystic pancreatic lesions. It is logical that EUS-guided pancreatic duct aspiration may be useful in cases of suspected intraductal or duct-obstructing tumors. We evaluated the safety and efficacy of EUS-guided pancreatic duct aspiration. PATIENTS AND METHODS: Twelve patients with dilated pancreatic ducts underwent EUS-guided duct aspiration. Aspirates were submitted for cytology and mucin staining. Patients were followed for up to 13 months. RESULTS: There were no procedure-related complications. Cytology was diagnostic in nine of the 12 patients (six with intraductal papillary mucinous tumor, one with pancreatic clonorchiasis, and two with obstructing solid pancreatic adenocarcinomas). Cytology in the remaining three patients, all with solid obstructing masses, was nondiagnostic. Overall, the diagnostic yield was 75%; however, the yield was 100% in patients without extrinsic obstruction. CONCLUSION: This preliminary experience suggests that EUS-guided pancreatic duct aspiration is safe and can provide diagnostic material in a significant number of patients with unexplained pancreatic duct dilation.

Effects of 10-hydroxycamptothecin, delivered from locally injectable poly(lactide-co-glycolide) microspheres, in a murine human oral squamous cell carcinoma regression model.

This study investigated whether local delivery of 10-hydroxycamptothecin provides effective inductive chemotherapy as assessed by significant tumor reduction. Established tumorigenic human oral squamous cell carcinoma cells were used for these experiments. The experimental groups were comprised of: control (blank (no drug) poly(lactide-co-glycolide) (PLGA) microspheres), intraperitoneal 10-hydroxycamptothecin delivery + blank microspheres, local bolus 10-hydroxycamptothecin + blank microspheres, and PLGA controlled-release microspheres. The 10-hydroxycamptothecin dose administered was 12 mg/kg (bolus-intraperitoneal, local) or controlled-release over 10 days. Regardless of delivery route, 10-hydroxycamptothecin significantly reduces tumor volume. However, PLGA microspheres provide significantly higher intratumor-drug concentrations (approximately 10 and 100 fold higher) relative to local bolus and intraperitoneal routes, respectively. Also, only the PLGA microspheres significantly reduced tumor weights. Camptothecin clinical applications are limited by drug inactivation at physiological pH and the need for sustained infusions. However, due to their acidic, camptothecin-stabilizing microclimate, PLGA microspheres could provide a novel delivery system for camptothecin-based induction chemotherapy.

Current status of diagnostic and therapeutic endoscopic ultrasonography.

Endoscopic ultrasonography is firmly established as an imaging modality that can be used for diagnosing and staging both malignant and nonmalignant disorders of the pancreas, gastrointestinal tract, biliary tree, and mediastinum. In the future, as more physicians are trained and as technologic developments continue to advance, endosonography will likely assume a greater role in therapeutic management.

The reliability of EUS for the diagnosis of chronic pancreatitis: interobserver agreement among experienced endosonographers.

BACKGROUND: Endoscopic ultrasound (EUS) is a minimally invasive, low risk method of diagnosis for chronic pancreatitis (CP). The degree to which endosonographers agree on the features and diagnosis of CP is unknown. For EUS to be considered an accurate test for CP, there must be good interobserver agreement. METHODS: Forty-five pancreatic EUS examinations were videotaped by 3 experienced endosonographers. Examinations from 33 patients with suspected CP based on typical symptoms, as well as 12 control patients without suspected CP, were included. Eleven experienced endosonographers ("experts") who were blinded to clinical information independently evaluated all videotaped examinations for the presence of CP and the following 9 validated features of CP: echogenic foci, strands, lobularity, cysts, stones, duct dilatation, duct irregularity, hyperechoic duct margins, and visible side branches. The experts also ranked (most to least) which features they believed to be the most indicative of CP. Interobserver agreement was expressed as the kappa (kappa) statistic. RESULTS: There was moderately good overall agreement for the final diagnosis of CP (kappa = 0.45). Agreement was good for individual features of duct dilatation (kappa = 0.6) and lobularity (kappa = 0.51) but poor for the other 7 features (kappa < 0.4). The expert panel had consensus or near consensus agreement (greater than 90%) on 206 of 450 (46%) individual EUS features including 22 of 45 diagnoses of CP. Agreement on the final diagnosis of CP was moderately good for those trained in third tier fellowships (kappa = 0.42 +/- 0.03) and those with more than 1100 lifetime pancreatic EUS examinations (kappa = 0.46 +/- 0.05). The presence of stones was regarded as the most predictive feature of CP by all endosonographers, followed by visible side branches, cysts, lobularity, irregular main pancreatic duct, hyperechoic foci, hyperechoic strands, main pancreatic duct dilatation, and main duct hyperechoic margins. The most common diagnostic criterion for the diagnosis of CP was the total number of features (median 4 or greater, range 3 or greater to 5 or greater). CONCLUSIONS: EUS is a reliable method for the diagnosis of chronic pancreatitis with good interobserver agreement among experienced endosonographers. Agreement on the EUS diagnosis of chronic pancreatitis is comparable to other commonly used endoscopic procedures such as bleeding ulcer stigmata and computed tomography of the brain for stroke localization and better than the physical diagnosis of heart sounds.

Controlled-release of doxorubicin from poly(lactide-co-glycolide) microspheres significantly enhances cytotoxicity against cultured AIDS-related Kaposi's sarcoma cells.

Subsequent to the introduction of highly active antiretroviral therapy (HAART), there has been a reduction in HIV viral titers and a concomitant decrease in AIDS-related Kaposi's sarcoma. However, as failure rates of HAART approach 30%, concerns arise regarding resurgence in AIDS-KS. Current AIDS-KS therapies fail to provide sustained remissions and yet also result in significant morbidity. Although partially effective, systemic chemotherapy is particularly debilitating to AIDS patients. In this report, we examined the co-incubation of AIDS-KS cells with doxorubicin which was slowly delivered from biodegradable, locally injectable, controlled-release poly(lactide-co-glycolide) (PLGA) microspheres. Local drug delivery systems such as PLGA microspheres can sustain therapeutic intralesional concentrations while minimizing deleterious systemic side effects, providing a pharmacologic advantage at the treatment site. Our data show that controlled release from PLGA microspheres augments doxorubicin cytotoxicity towards AIDS-KS cells without increasing toxicity in nonlesional cells from the AIDS-KS donors. Electron microscopic analysis revealed that PLGA microspheres possess a strong affinity for cell membranes, facilitating doxorubicin delivery to redox-sensitive cell membrane sites. Consistent with their speculated endothelial cell lineage, some of the AIDS-KS cells appeared to engulf microspheres via phagocytosis. Our results suggest that PLGA controlled-release doxorubicin microspheres have potential clinical applicability in management of AIDS-KS.

Advances in diagnostic and therapeutic endoscopy.

Endoscopy is extremely valuable in the evaluation of disorders of the luminal gastrointestinal tract, pancreas, and biliary system. Endoscopy as a medical discipline continues to evolve and is becoming increasingly therapeutic in nature. Minimally invasive endoscopic intervention now is effective in a wide variety of disorders, including gastrointestinal hemorrhage, obstructive diseases of the intestinal or biliary tree, and early detection or prevention of neoplastic disease of the colon and esophagus. The development of EUS technology has expanded greatly the potential utility of endoscopy as a diagnostic and a therapeutic modality, and further technologic advances are anticipated.

Sustained angiogenesis enables in vivo transplantation of mucocutaneous derived AIDS-related Kaposi's sarcoma cells in murine hosts.

AIDS-related Kaposi's sarcoma (AIDS-KS), the most prevalent HIV-associated malignancy, is a debilitating, potentially fatal disease. Currently, there is a need for development of AIDS-KS therapies that are not only well tolerated, but also capable of providing sustained remission. Preclinical assessment of pharmacological parameters and therapeutic efficacies are dependent upon in vivo parameters. However, there are currently no animal KS models and mucocutaneous KS cell isolates have proved to be non-tumorigenic in animal hosts. This report describes the development of a murine model that enables in vivo transplantation of 'native' low population doubling level AIDS-KS cells from biopsy-confirmed mucocutaneous lesions. The angiogenic phenotype of in situ AIDS-KS lesions is reconstituted via controlled release of a complete angiogenic peptide, recombinant human basic fibroblast growth factor (bFGF), from locally injectable, biodegradable polylactide-co-glycolide implants. Consequential to the sustained local release of bioactive bFGF, a murine vascular network is established, which facilitates the in vivo transplantation of AIDS-KS cells. Desirable aspects of this model include: low cost murine species, transplantation of non-selected patient cells and use of animal hosts that are T cell-deficient. The transplanted human AIDS-KS cells and extensive murine vascular network create lesions that retain a striking resemblance, at both the gross and microscopic levels, to in situ AIDS-KS tumors. Because the bFGF-induced murine vascular network is analogous to the abundant vascularity present in AIDS-KS lesions, this murine model should provide an excellent vehicle for numerous clinically relevant studies, such as assessment of drug clearance at AIDS-KS lesional sites. Finally, applicability of this method is not restricted to AIDS-related malignancies. Establishment and maintenance of an extensive host vascular network should augment success rates for in vivo transplantation of numerous other human cell strains or lines.

Interventional endoscopic ultrasonography: current status and future direction.

Although first performed more than 20 years ago, endoscopic ultrasonography (EUS) has only recently been used for interventional/therapeutic purposes. The recognition and application of this versatile procedure by gastroenterologists who perform endoscopy has reached an all-time high, and the demand for symposia and tutorials devoted to EUS rivals that of endoscopic retrograde cholangiopancreatography 20 to 25 years ago. EUS has become an established part of the endoscopic armamentarium for many gastroenterologists. Despite its proved clinical utility for staging gastrointestinal (and lung) cancers, and its use in delineating the nature of "submucosal" tumors of the gastrointestinal tract, EUS has continued to evolve. Within the past 10 years, the safety and efficacy of EUS as a means of guiding tissue acquisition via fine-needle aspiration has been demonstrated, increasing its utility in gastrointestinal oncology. Newer indications currently under clinical investigation include the use of EUS as a delivery mechanism for novel immune-based and viral-based "chemo" therapeutic agents for patients with pancreatic cancer. Finally, the role of EUS as a reliable method to guide therapy to control the often refractory abdominal pain in patients with pancreatic cancer and/or chronic pancreatitis is being verified in clinical trials. The following is a brief overview of the current state-of-the-art in interventional EUS.

EUS-guided radiofrequency ablation in the pancreas: results in a porcine model.

BACKGROUND: Our aim in this study was to investigate the feasibility and safety of performing radiofrequency (RF) ablation in the pancreas with endoscopic ultrasound (EUS). METHODS: RF was applied to normal pancreatic tissue in 13 anesthetized Yorkshire pigs with specially modified 19-gauge needle electrodes (1.0 to 1.5 cm tip). The pancreas was localized with EUS and punctured through a transgastric approach. RF current (285 +/- 120 mA) was delivered for 6 minutes. Diagnostic imaging (EUS and CT) and serum amylase and lipase levels were obtained at baseline, immediately after ablation, and 1 to 14 days after the procedure. Pigs were killed immediately (n = 5), 1 to 2 days after ablation (n = 2), and 2 weeks after the procedure (n = 6). Pathologic examination was performed. RESULTS: Sixteen ablations were performed. During ablation, round hyperechoic foci (diameter to 1.0 cm) gradually surrounded the tip of the electrode. Immediately after the procedure CT demonstrated 1 cm hypodense foci that did not enhance with iodinated contrast. In pigs killed immediately and 1 to 2 days after ablation, pathologic examination showed discrete, well-demarcated spherical foci of coagulation necrosis measuring 8 to 12 mm in diameter surrounded by a 1 to 2 mm rim of hemorrhage. Radiologic-pathologic correlation was within 2 mm. In 4 of 6 (67%) pigs killed on day 14, retraction of the coagulated focus was observed. A 1 to 3 mm fibrotic capsule surrounded the coagulated tissue in the remaining 2 pigs. One pig had mild hyperlipasemia, a focal zone of pancreatitis (<1 cm), and later a pancreatic fluid collection. Biochemical parameters were normal in the remaining pigs. Other complications included three gastric and one intestinal burn caused by improper electrode placement. CONCLUSIONS: EUS-guided RF ablation can be used safely to produce discrete zones of coagulation necrosis in the porcine pancreas. Potential clinical uses of this technology include management of small neuroendocrine tumors and possibly palliation of unresectable pancreatic adenocarcinoma.

Pretreatment staging by endoscopic ultrasonography does not predict complete response to neoadjuvant chemoradiation in patients with esophageal carcinoma.

BACKGROUND: Endoscopic ultrasonography (EUS) provides highly accurate preoperative T and N classifications in patients with esophageal carcinoma. Although previous data have suggested that patients with tumors classified as T4 by EUS do not benefit from surgical resection, these data were acquired prior to the widespread use of preoperative chemoradiation. The current study investigated whether pretreatment EUS can predict a complete response to neoadjuvant therapy. METHODS: Patients with esophageal carcinoma (adenocarcinoma or squamous cell carcinoma) underwent EUS classification prior to therapy. Patients classified as T2, T3, or T4 and M0 were treated with 5-fluorouracil, cisplatin, and radiation under protocol. Patients with T1 lesions underwent resection without prior chemoradiation. Chemoradiation was followed in all cases by attempted surgical resection. The initial EUS classification was compared with the final pathologic results. RESULTS: Fifty-five patients (47 males and 8 females) with a mean age of 60.5 years (range, 31-78 years) were evaluated. There were 41 adenocarcinomas and 14 squamous cell carcinomas. Among the total population, a complete response was achieved in 3 of 5 patients (60%) with tumors classified as T2 by EUS, 14 of 42 patients (33%) with tumors classified as T3 by EUS, and 5 of 8 patients (63%) with tumors classified as T4 by EUS (P = 0.19). A complete response was achieved in 9 of 24 patients (38%) found to have N0 disease by EUS versus 13 of 30 patients (43%) determined to have N1 disease (P = 0.66). The results for patients with adenocarcinoma and squamous cell carcinoma were similar. CONCLUSIONS: The results of the current study demonstrate that pretreatment EUS does not predict reliably which patients with esophageal carcinoma will achieve a complete pathologic response to preoperative neoadjuvant chemoradiation.

Increased rate of complete EUS staging of patients with esophageal cancer using the nonoptical, wire-guided echoendoscope.

BACKGROUND: Incomplete endoscopic ultrasound (EUS) staging procedures in patients with esophageal cancer due to obstructing malignant strictures are prone to underestimate T stage and cannot detect celiac adenopathy. EUS staging in the setting of stenotic malignancies using the large caliber echoendoscope has been complicated by esophageal perforation. We report on the clinical utility of a newly developed, wire-guided echoendoscope for the complete staging of patients with esophageal cancer. METHODS: Pretreatment EUS examinations performed for esophageal cancer staging were evaluated and the ability to traverse the esophagus and examine the celiac axis were documented. Outcomes before and after the availability of the wire-guided echoendoscope were compared. RESULTS: One hundred thirty consecutive examinations were evaluated 100 before and 30 after the introduction of the wire-guided echoendoscope. Complete staging was accomplished in 60 of 100 (60%) cases before and 27 of 30 (90%) after its introduction (p = 0.002). The wire-guided echoendoscope was used in 14 of the 30 cases. Despite a trend toward fewer stage T4 tumors, metastatic disease was documented significantly more frequently after the introduction of the esophagoprobe (34% vs. 11%, p = 0.002). There were no complications. CONCLUSIONS: The introduction of the wire-guided echoendoscope markedly reduced the occurrence of incomplete esophageal cancer staging and improved the detection of metastatic disease.

Thiol redox modulation of doxorubicin mediated cytotoxicity in cultured AIDS-related Kaposi's sarcoma cells.

The chemotherapeutic, doxorubicin, is currently used empirically in the treatment of AIDS- related Kaposi's sarcoma (AIDS-KS). Although often employed in a chemotherapeutic cocktail (doxorubicin, bleomycin, vincristine) single-agent therapy has recently been attempted with liposome encapsulated doxorubicin. Although doxorubicin's mechanism of action against AIDS-KS is unknown, we hypothesized that doxorubicin's ability to undergo redox cycling is associated with its clinical efficacy. The current study was conducted to investigate the effects of doxorubicin on selected xenobiotic-associated biochemical responses of three cellular populations: KS lesional cells, nonlesional cells from the KS donors, and fibroblasts obtained from HIV- aged matched men. Our results show that during doxorubicin challenge, there are strong positive correlations between cellular glutathione (GSH) levels and viability (r = 0.94), NADPH levels and viability (r = 0.93), and GSH and NADPH levels (r = 0.93), and demonstrate that as a consequence of their abilities to maintain cellular thiol redox pools HIV- donor cells are significantly less susceptible to doxorubicin's cytotoxic effects relative to AIDS-KS cells. Additional studies further supported the contribution of reduced thiols in mediating doxorubicin tolerance. While pretreatment with the GSH precursor, N-acetylcysteine was cytoprotective for all cell groups during doxorubicin challenge, GSH depletion markedly enhanced doxorubicin's cytotoxic effects. Studies to investigate the effects of a hydroxyl scavenger and iron chelator during doxorubicin challenge showed moderate cytoprotection in the AIDS-KS cells but deleterious effects in the HIV control cells. Inactivation of the longer lived membrane generated ROI in the cytoprotective deficient AIDS-KS cells, as well as an impairment of endogenous defenses in the HIV- donor control cells, may account for these scavenger and chelator associated findings. In summary, our findings show that doxorubicin mediates, at least in part, its AIDS-KS cellular cytotoxic effects by a redox related mechanism, and provides a biochemical rationale for doxorubicin's clinical efficacy in AIDS-KS treatment.

The endogenous antioxidant glutathione as a factor in the survival of physically injured mammalian spinal cord neurons.

Glutathione is part of the system of cellular defenses against lipid peroxidation and other free radical-mediated damage. An established in vitro trauma model was utilized to evaluate whether glutathione is a factor in the survival of mammalian spinal cord neurons following physical injury. Cultured murine spinal neurons were subjected to a standard lesion: transection of a primary dendrite 100 microm from the perikaryon. Prior reduction of glutathione with ethacrynic acid or buthionine sulfoximine caused a dose-dependent decrease in neuronal survival 24 hours after dendrotomy. Prior glutathione augmentation with gamma-glutamylcysteine or L-2-oxo-4-thiazolidine carboxylic acid significantly increased survival, but N-acetyl-cysteine was not protective. Gamma glutamylcysteine effected the most rapid increase in glutathione (peak at 10 min), and survival was 72% +/- 10 when 0.2 mM gamma-glutamylcysteine was added immediately after dendrotomy compared with 38% +/- 4 in the control group (p < 0.0001). These results indicate that the level of glutathione is a factor in spinal cord neuron survival after physical trauma, and that glutathione augmentation may be an effective acute phase spinal cord injury (SCI) intervention strategy.