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M A Choti

Publications and source records attributed to M A Choti.

At least 37 records · Page 2Linked to original sources
PubMed1999

Hospital volume can serve as a surrogate for surgeon volume for achieving excellent outcomes in colorectal resection.

OBJECTIVE: To examine the association of surgeon and hospital case volumes with the short-term outcomes of in-hospital death, total hospital charges, and length of stay for resection of colorectal carcinoma. METHODS: The study design was a cross-sectional analysis of all adult patients who underwent resection for colorectal cancer using Maryland state discharge data from 1992 to 1996. Cases were divided into three groups based on annual surgeon case volume--low (< or =5), medium (5 to 10), and high (>10)--and hospital volume--low (<40), medium (40 to 70), and high (> or =70). Poisson and multiple linear regression analyses were used to identify differences in outcomes among volume groups while adjusting for variations in type of resections performed, cancer stage, patient comorbidities, urgency of admission, and patient demographic variables. RESULTS: During the 5-year period, 9739 resections were performed by 812 surgeons at 50 hospitals. The majority of surgeons (81%) and hospitals (58%) were in the low-volume group. The low-volume surgeons operated on 3461 of the 9739 total patients (36%) at an average rate of 1.8 cases per year. Higher surgeon volume was associated with significant improvement in all three outcomes (in-hospital death, length of stay, and cost). Medium-volume surgeons achieved results equivalent to high-volume surgeons when they operated in high- or medium-volume hospitals. CONCLUSIONS: A skewed distribution of case volumes by surgeon was found in this study of patients who underwent resection for large bowel cancer in Maryland. The majority of these surgeons performed very few operations for colorectal cancer per year, whereas a minority performed >10 cases per year. Medium-volume surgeons achieved excellent outcomes similar to high-volume surgeons when operating in medium-volume or high-volume hospitals, but not in low-volume hospitals. The results of low-volume surgeons improved with increasing hospital volume but never equaled those of the high-volume surgeons.

Aged↗
PubMed1998

Gamma probe-directed biopsy of the sentinel node in oral squamous cell carcinoma.

OBJECTIVE: Management of the N0 neck in head and neck squamous cell carcinoma is an important issue for the head and neck surgeon. Experience with radionuclide-labeled colloid injection to identify a sentinel node in malignant melanoma suggests a high level of accuracy for this approach to identify microscopic metastasis when present. We set out to explore the feasibility of using the handheld gamma probe to identify radiolabeled sentinel nodes in oral squamous cell carcinoma. PATIENT POPULATION: Five individuals with N0 necks and accessible oral or oropharyngeal primary sites from a major tertiary referral center. METHODS: Radiolabel with unfiltered technetium Tc 99m sulfur colloid was injected in quadrants around the primary site followed by immediate dynamic lymphoscintigraphy. Open biopsy of the sentinel node was accomplished within 2 hours of injection after extirpation of the primary site. Regional or complete neck dissection was performed after sentinel node biopsy. RESULTS: Sentinel node biopsy accurately identified one or several nodes in 2 cases, including nodes containing metastatic cancer in 1. In the other 3 cases, the radiolabel failed to identify the sentinel node despite the presence of metastatic disease in the nodes at final pathologic study in 2. CONCLUSIONS: Detection and biopsy of the sentinel node are feasible for selected patients with oral head and neck squamous cell carcinoma with N0 necks. There is a potential savings of time, cost, and morbidity with this approach. However, several substantial problems were encountered with the technique in this limited series of patients. Establishing the reliability of lymphoscintigraphy in this setting would require testing in a much larger patient cohort. Our experience suggests that such an investment may not be warranted.

Adult↗
PubMed1998

Association between extent of axillary lymph node dissection and survival in patients with stage I breast cancer.

BACKGROUND: The role of axillary lymph node dissection for stage I (T1N0) breast cancer remains controversial because patients can receive adjuvant chemotherapy regardless of their nodal status and because its therapeutic benefit is in question. The purpose of this study was to determine whether extent of axillary dissection in patients with T1N0 disease is associated with survival. METHODS: Data from 464 patients with T1N0 breast cancer who underwent axillary dissection from 1973 to 1994 were examined retrospectively. Kaplan-Meier estimates of overall survival, disease-free survival, and recurrence were calculated for patients according to the number of lymph nodes removed (<10 or > or = 10; <15 or > or = 15), and survival curves compared using the Wilcoxon-Gehan statistic. Cox proportional hazards regression modelling was used to adjust for confounding prognostic variables. RESULTS: Median follow-up time was 6.4 years. Patient groups were similar in age, menopausal status, tumor size, hormonal receptor status, type of surgery, and adjuvant therapy. There was a statistically significant improvement in disease-free survival in the > or = 10 versus <10 nodal groups (P <.01). Five-year estimates of survival were 75.7% and 86.2% for <10 nodes and > or = 10 nodes, respectively; 10-year estimates were 66.1% and 74.3%. There also was a notable improvement in the survival comparison of patients with <15 versus > or = 15 nodes (P < or = .05). These findings were confirmed in the multivariate analysis. CONCLUSIONS: These results may reflect a potential for misclassification of tumor stage among patients who had fewer nodes removed. The data, however, suggest that in patients with Stage I breast cancer, improved survival is associated with a more complete axillary lymph node dissection.

Adult↗
PubMed1998

Isolated liver metastases from neuroendocrine tumors: does resection prolong survival?

BACKGROUND: Neuroendocrine tumors commonly metastasize to the liver. Although surgical resection is considered a treatment option for patients with localized metastases confined to the liver, the longterm survival benefit of liver resection has not been clearly demonstrated. We examined the survival of patients undergoing liver resection for this disease. STUDY DESIGN: Between 1984 and 1995, we evaluated 38 patients with liver-only metastases from neuroendocrine tumors, including 21 carcinoid, 13 islet cell, and 4 atypical neuroendocrine neoplasms. Data from a combined prospective and retrospective database and a tumor registry were analyzed. Of these patients, 15 underwent complete resection of all known disease. The remaining 23 patients, who also had disease confined to the liver, had comparable tumor burden but were believed to be unresectable. The longterm survival rates of these two groups were compared. RESULTS: Patients who underwent liver resection did not differ from those who were unresectable with regard to age, pathology, primary tumor site, serum alkaline phosphatase levels, or percentage of the liver involved. All resections were complete, leaving no residual disease, and consisted of lobectomy (n = 3), segmentectomy (n = 1), and wedge resections (n = 11). There were no operative deaths. Patients who underwent hepatic resection had a significantly longer survival than unresected patients. Although median survival had not been reached in resected patients, the median survival in the unresectable group was 27 months. Patients who underwent liver resection had a higher 5-year actuarial survival (73% versus 29%). CONCLUSIONS: Hepatic resection in selected patients with isolated liver metastases from neuroendocrine tumors may prolong survival. This conclusion was reached by comparing our resected group with an unresectable group with similar tumor burden.

Female↗
PubMed1998

K-ras oncogene mutations in osteoclast-like giant cell tumors of the pancreas and liver: genetic evidence to support origin from the duct epithelium.

Osteoclast-like giant cell tumors (OCGTs) of the pancreas and liver are enigmatic tumors. Despite their striking morphologic resemblance to certain mesenchymal tumors of bone and tendon sheath, it has been suggested that these tumors may, in fact, arise from epithelial precursors. It is also unclear whether the osteoclast-like giant cells in OCGTs are neoplastic or nonneoplastic. We identified OCGTs of the pancreas and liver that were associated with atypical intraductal epithelial proliferations or mucinous cystic neoplasms. To determine the relationship between the noninvasive epithelial proliferations and the infiltrating OCGTs, each individual component was analyzed for mutations at codon 12 of the K-ras oncogene. Four of the five-duct epithelial lesions harbored activating mutations of the K-ras oncogene. In each case, the same K-ras mutation was also present in the mononuclear cells from the paired OCGT. Moreover, these same mutations were detected when the osteoclast-like giant cells were individually microdissected and analyzed. A panel of immunohistochemical stains was performed, and the osteoclast-like giant cells demonstrated macrophage differentiation. These cells were consistently reactive for the monocyte/macrophage marker KP1, but showed absent staining for a panel of epithelial markers. The infiltrating mononuclear cells lacked strong staining for epithelial markers and monocyte/macrophage markers. These findings suggest that OCGTs of the pancreas and liver are undifferentiated carcinomas that arise directly from intraductal epithelial precursors. The finding of K-ras mutations in the osteoclast-like giant cells may reflect their propensity to phagocytize tumor cells.

Antigens, CD↗
PubMed1997

Intraoperative and laparoscopic sonography of the liver.

Intraoperative sonography is an important aid in the decision making process during open surgery because it can detect additional small liver tumours that may not be depicted preoperatively, even with the use of modern non invasive imaging modalities. A continued important role of intraoperative sonography is to determine hepatic anatomy, allowing for safer and easier hepatic surgery with increased parenchymal preservation. Intraoperative sonography is also used for monitoring cryogenic ablation of hepatic tumour. To overcome the inherent limitations of laparoscopic surgery, laparoscopic sonography can now be used to provide information not available during laparoscopy or laparoscopic surgery alone. In this article, the authors present the most recent techniques for intraoperative sonography. Also they emphasize the important role of intraoperative sonography and laparoscopic sonography in the surgical decision-making process in patients with hepatic or biliary disease and report the most recent advances in intraoperative sonography with respect to the treatment of hepatic tumours. Finally, they try to look forward at the possible use for intraoperative technologies that are now in their early stages.

Hepatectomy↗
PubMed1996

Portal-phase contrast-enhanced helical CT for the detection of malignant hepatic tumors: sensitivity based on comparison with intraoperative and pathologic findings.

OBJECTIVE: The purpose of this study was to determine the sensitivity of portal-phase IV contrast-enhanced helical CT in detecting malignant hepatic tumors using a lesion-by-lesion comparison with surgical and pathologic findings. MATERIALS AND METHODS: Preoperative portal-phase contrast-enhanced helical CT studies in 21 patients (13 men, eight women) with malignant neoplasms of the liver (12 patients with primary hepatic tumors, nine patients with metastases) were reviewed retrospectively by three radiologists with the knowledge that hepatic malignancies were present in each case. Helical CT findings were compared with intraoperative findings by palpation (21 patients), sonography (15 patients), and the results of pathologic examination of resected specimens (10 patients) in a lesion-by-lesion manner. Sixty-four malignant nodules were identified in resected specimens or at surgery by palpation or intraoperative sonography. For each nodule identified by surgical or pathologic means, CT findings were reviewed for the presence of a lesion of similar size and location. RESULTS: The readers identified 52 of 64 nodules on helical CT scans for an overall sensitivity of 81%. Sixteen of 21 primary tumors (76%) and 36 of 43 metastatic tumors (84%) were identified on CT scans. The sensitivity was 91% for nodules greater than 1 cm (42 of 46) and 56% for nodules 1 cm or less (10 of 18). False-positive findings occurred in 4% of lesions seen on helical CT scans. CONCLUSION: Our results show that portal-phase contrast-enhanced helical CT is extremely sensitive (91%) for detecting malignant hepatic tumors greater than 1 cm, is relatively insensitive (56%) for tumors less than 1 cm, and has a low false-positive rate. These results compare favorably with published results for CT during arterial portography, the current gold standard for liver tumor detection, suggesting that portal-phase IV contrast-enhanced helical CT is an excellent noninvasive preoperative study prior to hepatic resection or cryosurgery.

Adult↗
PubMed1996

Hepatic tumors treated by cryosurgery: normal CT appearance.

OBJECTIVE: An understanding of the normal appearance of hepatic tumors treated with cryosurgery is essential for accurately distinguishing normal postoperative changes from potential complications such as hepatic abscess or infarct, which may necessitate further interventions. The purpose of this study was to characterize the normal spectrum of CT findings after cryoablation of hepatic tumors. SUBJECTS AND METHODS: The CT scans of 14 patients who had undergone hepatic cryoablation 4-16 days (mean, 7 days) before scanning were reviewed by three radiologists. None of these patients had postprocedural complications that necessitated intervention (e.g. abscess, infarct, or hemorrhage). Indications for cryoablation included primary hepatic tumors in four patients and hepatic metastases in 10 patients. CT findings were correlated with surgical findings in a lesion-by-lesion manner to ensure that only cryolesions were included in the analysis. RESULTS: Twenty-eight cryolesions from 3 to 11 cm maximum diameter (mean, 7 cm) were detected on CT scans. All cryolesions were primarily hypodense and extended to the liver capsule. Ten (36%) of 28 lesions contained air, and 26 (93%) of 28 lesions contained hemorrhage. Thirteen (54%) of 24 lesions evaluated with i.v. contrast material showed peripheral enhancement. Cryolesions were primarily wedge shaped (54%), round (29%), or teardrop shaped (21%). One iatrogenic portosystemic shunt was detected. Other associated findings included subcapsular hemorrhage (29%), perihepatic fluid collections (43%), right-sided pleural effusion (93%), left-sided pleural effusion (64%), atelectasis of one or both lungs (93%), and ascites (7%). CONCLUSION: The postoperative CT appearance of the liver in patients who underwent hepatic cryoablation without complications mimics that seen in the liver of patients with hepatic abscesses or infarcts. The CT appearance of the liver in patients undergoing cryosurgery needs to be carefully analyzed to avoid confusing normal findings related to the procedure with those related to procedural complications, it may be impossible to differentiate hepatic complications from normal postoperative changes on the basis of CT findings in many of these patients.

Cryosurgery↗
PubMed1995

Three-dimensional spiral CT during arterial portography: comparison of three rendering techniques.

The three most common techniques for three-dimensional reconstruction are surface rendering, maximum-intensity projection (MIP), and volume rendering. Surface-rendering algorithms model objects as collections of geometric primitives that are displayed with surface shading. The MIP algorithm renders an image by selecting the voxel with the maximum intensity signal along a line extended from the viewer's eye through the data volume. Volume-rendering algorithms sum the weighted contributions of all voxels along the line. Each technique has advantages and shortcomings that must be considered during selection of one for a specific clinical problem and during interpretation of the resulting images. With surface rendering, sharp-edged, clear three-dimensional reconstruction can be completed on modest computer systems; however, overlapping structures cannot be visualized and artifacts are a problem. MIP is computationally a fast technique, but it does not allow depiction of overlapping structures, and its images are three-dimensionally ambiguous unless depth cues are provided. Both surface rendering and MIP use less than 10% of the image data. In contrast, volume rendering uses nearly all of the data, allows demonstration of overlapping structures, and engenders few artifacts, but it requires substantially more computer power than the other techniques.

Algorithms↗
PubMed1995

Variations in the intrahepatic portions of the hepatic and portal veins: findings on helical CT scans during arterial portography.

OBJECTIVE: The goals of this study were to describe variations in the intrahepatic portions of the hepatic and portal veins as visualized by helical CT during arterial portography (CTAP) and to examine the surgical implications of these findings. MATERIALS AND METHODS: A retrospective review of 69 helical CTAP scans of 69 patients with small hepatic tumors and no evidence of vascular invasion or distortion was done. Axial helical CTAP scans were reviewed to determine the presence, number, and location of intrahepatic portions of the hepatic and portal veins. RESULTS: Among the 60 patients (87%) in whom the right, middle, and left hepatic veins were visualized, 19 (32%) had supernumerary hepatic veins. Right inferior hepatic veins were found in six (9%) of the 69 patients. Variations in intrahepatic portal anatomy were found in four patients (6%) and involved an immediate trifurcation of the portal vein in three patients (4%) and a left main portal vein originating from the right anterior portal branch in one patient (2%). CONCLUSION: Variations in the intrahepatic portions of the hepatic and portal veins are frequently seen on helical CTAP scans. Recognition of such variations is important in the preoperative evaluation of patients with hepatic tumors because these variations may have implications for tumor resection and for planning the operative approach.

Adult↗
PubMed1990

Induction of donor-specific unresponsiveness by intrathymic islet transplantation.

The application of isolated pancreatic islet transplantation for treatment of diabetes mellitus has been hampered by the vulnerability of islet allografts to immunologic rejection. Rat islet allografts that were transplanted into the thymus of recipients treated with a single injection of anti-lymphocyte serum survived indefinitely. A state of donor-specific unresponsiveness was achieved that permitted survival of a second donor strain islet allograft transplanted to an extrathymic site. Maturation of T cell precursors in a thymic microenvironment that is harboring foreign alloantigen may induce the selective unresponsiveness. This model provides an approach for pancreatic islet transplantation and a potential strategy for specific modification of the peripheral immune repertoire.

Animals↗
PubMed1989

Modulation of the major histocompatibility complex antigen and the immunogenicity of islet allografts.

Modulation of major histocompatibility complex (MHC) antigen by parenchymal cells and "passenger leukocytes" is a common feature of allograft rejection. To assess its significance we have examined the fate of antigen-presenting cell (APC)-depleted pancreatic islet allografts subsequent to increasing their expression of MHC antigens by in vitro exposure to the lymphokine interferon-gamma (gIFN). While most untreated grafts survived indefinitely, gIFN-exposed grafts were acutely rejected. Using in vitro islet cell-lymphocyte coculture assays, we attempted to dissect the underlying mechanism of enhanced islet cell immunogenicity resulting from gIFN treatment. We determined that gIFN exposure did not affect the capacity of islet cells to serve as APC for T lymphocytes, however islet cell exposure to gIFN was associated with enhanced vulnerability to allogeneic cytotoxic T lymphocyte (CTL) lysis in vitro by an CD5+ (OX-19+), CD8+ (OX-8+), CD4- (W3/25-), class I-restricted CTL. On the basis of these findings, we conclude that antigenic modulation can be a decisive factor in the survival of engrafted tissues by augmenting the interaction of the graft antigens with cytolytic effector T lymphocytes.

Animals↗
PubMedDate not supplied

Isolated right segmental hepatic duct injury: a diagnostic and therapeutic challenge.

Biliary leaks and injuries are not an uncommon occurrence following laparoscopic cholecystectomy. Bile leaks associated with the biliary anatomic variant of a low-inserting right segmental hepatic duct can be particularly difficult to diagnose in that results of endoscopic retrograde cholangiography (ERC) are usually interpreted as "normal" with no leaks demonstrated. The aim of this study was to describe a single institution's experience with nine patients with biliary leaks associated with this anatomic variant and to discuss their management. A retrospective analysis of the hospital records of all patients with bile duct injuries managed at a single institution between 1980 and July 1998, inclusive, was performed. Nine patients were identified as having an isolated right segmental hepatic duct injury associated with a biliary leak. Seven (78%) of the nine patients had undergone a laparoscopic cholecystectomy, whereas the remaining two patients (22%) had undergone an open cholecystectomy. All of the patients had undergone endoscopic retrograde cholangiography at outside institutions, the results of which had been interpreted as normal with no apparent leaks. The median interval from the time of cholecystectomy to referral was 1.4 months. All patients were managed with initial percutaneous access of the involved right segmental biliary system, with placement of a percutaneous transhepatic stent. After the biliary leak was controlled, all patients underwent Roux-en-Y hepaticojejunostomy to the isolated biliary segment. All patients had an uncomplicated postoperative course. There were no postoperative anastomotic leaks. Postoperative stenting was maintained for a mean of 8 months. Six (67%) of the nine patients had a long-term successful outcome with minimal or no symptoms. In three patients, recurrent symptoms with pain and/or cholangitis developed at a mean of 34 months. All three patients underwent percutaneous cholangiography, which demonstrated an anastomotic stricture, and all were managed with percutaneous balloon dilatation with a successful outcome. Currently eight (89%) of the nine patients are asymptomatic, with a mean follow-up of 70.4 months (range 12 to 226 months). One patient had intermittent right upper quadrant pain with normal liver function tests but has not required intervention. Isolated right segmental hepatic ductal injury with biliary leakage is an uncommon complication following laparoscopic cholecystectomy. A diagnostic dilemma is created by the presence of a bile leak with a normal endoscopic retrograde cholangiogram. Management begins with percutaneous access of the transected isolated ductal system followed by reconstruction as a Roux-en-Y hepaticojejunostomy.

Adult↗
PubMedDate not supplied

Results of salvage abdominoperineal resection for recurrent anal carcinoma following combined chemoradiation therapy.

Combined chemotherapy and radiation therapy is the standard treatment for epidermoid carcinoma of the anal canal. Failures are often not associated with distant recurrence and are therefore potentially amenable to salvage abdominoperineal resection. The aim of this study was to review our experience with abdominoperineal resection following failure of chemoradiation therapy for epidermoid carcinoma of the anus. Between 1980 and 1998, 17 patients underwent salvage abdominoperineal resection following failure of chemoradiation therapy. Four patients were excluded from survival analysis because resection was performed with palliative intent. Survival curves were based on the method of Kaplan and Meier, and univariate analysis of predictive variables was performed using the log-rank test. Twelve patients underwent abdominoperineal resection for persistent disease and five patients for recurrent disease. No operative deaths occurred, but local complications including perineal wound infection and wound breakdown was seen in 8 of 17 patients and 6 of 17 patients, respectively. Patients undergoing omental flap reconstruction (n = 3) or no pelvic reconstruction (n = 5) had a higher incidence of perineal breakdown compared to those undergoing muscle flap reconstruction (n = 9) (P <0.05). The median follow-up time for the patients operated on with curative intent was 53 months. The 5-year actuarial survival was 47%. Potential prognostic factors that were not found to have an impact on survival included margin status of resection, sphincter invasion, and degree of differentiation. Only pathologic tumor size greater than 5.0 cm (P <0.001) and age over 55 years (P <0.05) adversely affected survival. Selected patients with recurrent or persistent anal carcinoma following chemoradiation therapy can be offered salvage abdominoperineal resection. This operation is associated with a high incidence of local wound complications, and muscle flap reconstruction should be considered when possible. Prolonged survival can be achieved in some patients following salvage resection for epidermoid carcinoma of the anal canal.

Anus Neoplasms↗
PubMedDate not supplied

Acute isovolemic hemodilution during major hepatic resection--an initial report: does it safely reduce the blood transfusion requirement?

Surgical resection remains the mainstay of treatment for patients with hepatic tumors, despite the associated morbidity including the need for blood transfusion. Acute isovolemic hemodilution (AIH) has been shown to decrease the transfusion requirement for cardiac, urologic, and orthopedic procedures. However, the reported experience with AIH during hepatic resections is limited. Seven patients underwent major hepatic resection from July 1992 to June 1994 with standard AIH. Their clinical parameters were compared with those of nine matched control patients during the same time period. AIH and control patients had similar preoperative laboratory values (hematocrit, bilirubin, and coagulation studies), extent of liver resection, and pathologic diagnoses. Mean tumor diameters were larger in the AIH group (9.3 cm vs. 5.8 cm). Most important, patients managed with AIH required homologous blood transfusions significantly less often than the control group (14% vs. 67%; P=0.05). Furthermore, if they did receive transfusions, AIH patients needed fewer units of red cells (0.1+/-0.1 units vs. 1.7+/-0.6 units). There was no morbidity associated with AIH. AIH can be safely performed in patients undergoing major hepatic resection for malignancy. AIH appears to reduce the number of patients requiring homologous blood transfusion as well as the number of units transfused per patient. This technique warrants further study in a larger prospective, randomized trial.

Blood Loss, Surgical↗
PubMedDate not supplied

Complete hepatic resection of metastases from leiomyosarcoma prolongs survival.

Although liver resection has been shown to prolong survival in selected patients with metastases from colorectal cancer, the benefit for other metastatic tumors is unproved. To determine whether hepatic resection has a role in the management of metastatic leiomyosarcoma, medical records from 11 consecutive patients who underwent resection of isolated metastases from leiomyosarcoma between 1984 and 1995 were reviewed. All liver resections were for leiomyosarcomas originating in the viscera (n = 6) or retroperitoneum (n = 5). The average disease-free interval was 16 months. Five of 11 primary tumors were classified as low grade, whereas six were high grade. Hepatic resections included lobectomy or extended lobectomy (n = 4), segmentectomy and/or wedge resection (n = 5), and complex resection (n = 2). There were no operative deaths. Median survival of all patients after liver resection was 39 months. Patients who underwent complete resection of hepatic metastases (n = 6) had a significantly longer survival than those who had incomplete resections (n = 5) (P = 0.03, log-rank test). Furthermore, five of six patients who underwent complete resection are alive after hepatectomy with a median follow-up of 53 months. Therefore, in selected patients with isolated liver metastases from visceral and retroperitoneal leiomyosarcomas, complete resection of hepatic metastases results in prolonged survival.

Adult↗
PubMedDate not supplied

Should hepatic resections be performed at high-volume referral centers?

Recent studies have demonstrated the relationship between clinical outcomes of complex surgical procedures and provider volume. Hepatic resection is one such high-risk surgical procedure. The aim of this analysis was to determine whether mortality and cost of performing hepatic resection are related to surgical volume while also examining outcomes by extent of resection and diagnosis, variables seen with this procedure. Maryland discharge data were used to study surgical volume, length of stay, charges, and mortality for 606 liver resections performed at all acute-care hospitals between January 1990 and June 1996. One high-volume provider accounted for 43.6% of discharges, averaging 40.6 cases per year. In comparison, the remainder of resections were performed at 35 other hospitals, averaging 1.5 cases per year. Data were stratified into these high- and low-volume groups, and adjusted outcomes were compared. The mortality rate for all procedures in the low-volume group was 7.9% compared to 1.5% for the high-volume provider (P <0.01, relative risk = 5.2). No overall differences were observed between low- and high-volume providers in total hospital charges. When analyzing by procedure type and diagnosis, lower mortality was seen in the high-volume center for both minor and major resections, as well as resections for metastatic disease. It was concluded that hepatic resection can be performed more safely and at comparable cost at high-volume referral centers.

Black People↗