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Theory related to global, free-field cancellation of a primary monopole field by the use of a displaced, secondary multipole was presented previously: a corresponding experimental investigation is presented here. The construction of multipole source components to octopole order is described, as are procedures for determining their source strengths. Dipoles, longitudinal quadrupoles, and longitudinal octopoles that conformed closely to their theoretical models were constructed using arrays of unbaffled loudspeakers. Two methods of calculating the multipole strengths required to cancel a primary monopole field were implemented in an open-loop manner: a "direct" approach based on a multipole expansion of the primary field, and a least-squares procedure based on fitting the secondary field to the primary field either along a circle enclosing a secondary source, or along a segment of that circle. Cancellation measurements were made on a 1-m-radius circle centered on the secondary source: the primary-to-secondary source separation was approximately 0.2 wavelengths. It was found both that a secondary multipole could provide far greater cancellation than a monopole placed at the same distance from the primary source and that the least-squares approach resulted in greater far-field cancellation than did the direct approach.

A method for evaluating the acoustical properties of homogeneous and isotropic porous materials that may be modeled as fluids having complex properties is described here. To implement the procedure, a conventional, two-microphone standing wave tube was modified to include: a new sample holder; a section downstream of the sample holder that accommodated a second pair of microphone holders and an approximately anechoic termination. Sound-pressure measurements at two upstream and two downstream locations were then used to estimate the two-by-two transfer matrix of porous material samples. The experimental transfer matrix method has been most widely used in the past to measure the acoustical properties of silencer system components. That procedure was made more efficient here by taking advantage of the reciprocal nature of sound transmission through homogeneous and isotropic porous layers. The transfer matrix of a homogeneous and isotropic, rigid or limp porous layer can easily be used to identify the material's characteristic impedance and wave number, from which other acoustical quantities of interest can be calculated. The procedure has been used to estimate the acoustical properties of a glass fiber material: good agreement was found between the estimated acoustical properties and those predicted by using the formulas of Delany and Bazley.

The initial reports of sentinel lymph node mapping for breast cancer currently appearing in the surgical literature are demonstrating the practicality and accuracy of the technique to evaluate patients for axillary nodal disease. We reviewed our initial 100 patient experience with sentinel node mapping to evaluate our ability to employ this technique in breast cancer patients. We combined a peritumoral injection of a radioactive substance and blue dye. Each sentinel node was evaluated with frozen section analysis, hematoxylin and eosin staining, and, if still negative, five re-cuts were taken from deeper levels of the node and evaluated for immunohistochemical evidence of cytokeratin staining. Sentinel node(s) were identified in all but two patients with 51% demonstrating metastasis. We have demonstrated the ability to accurately perform sentinel node mapping in the evaluation of our breast cancer patients. This exciting advance should become a standard part of breast cancer surgery.

Image-guided core-needle breast biopsy (IGCNBB) is widely used to evaluate patients with abnormal mammograms; however, information is limited regarding the reliability of a benign diagnosis. The goal of this study was to demonstrate that a benign diagnosis obtained by IGCNBB is accurate and amenable to mammographic surveillance. Records of all patients evaluated by IGCNBB from July 1993 through July 1996 were reviewed. Biopsies were classified as malignant, atypical, or benign. All benign cases were followed by surveillance mammography beginning 6 months after IGCNBB. Of the 1110 patients evaluated by IGCNBB during the study period, 855 revealed benign pathology. A total of 728 of the 855 patients (85%) complied with the recommendation for surveillance mammography. A total of 196 IGCNBBs were classified as malignant; 59 cases were classified as atypical. The atypical cases were excluded from the statistical analysis. Only two patients have demonstrated carcinoma after a benign IGCNBB during the 2-year minimum follow-up period. The sensitivity and specificity of a benign result were 100.0 and 98.9 per cent, respectively. A benign diagnosis obtained by IGCNBB is accurate and therefore amenable to mammographic surveillance. The results of this study support IGCNBB as the preferred method of evaluating women with abnormal mammograms.

Background: Male breast carcinoma is rare; therefore, the effect of family history on the course of the disease has not been well described. Germ-line mutations in breast carcinoma susceptibility genes, particularly BRCA2, are associated with an increased risk of male breast carcinoma. The authors sought to correlate significant family history with clinical phenotype in males with breast carcinoma., Methods: One hundred forty-two men with breast carcinoma were treated at Memorial Sloan-Kettering Cancer Center or the Ochsner Clinic from 1973 to 1994. The authors reviewed the effect imparted by a family history of breast carcinoma on the duration of symptoms, the age at diagnosis, and the survival of men with this disease., Results: Fifteen percent of male breast carcinoma patients had a first-degree relative with the disease. Fifty-eight years was the mean age at diagnosis for those with a family history, compared with 61 years for those without (P = not significant [NS]). The mean duration of symptoms was 23 months for those with a family history, compared with 22 months for those without. Three of 22 patients (13.6%) with a family history, compared with 11 of 90 patients (12%) without a family history, had Stage III disease (P = NS) at presentation. The overall 5-year and 10-year survival rates were 86% and 64%. Survival was not affected by family history. Lymph node positivity reduced 5-year and 10-year survival rates to 73% and 50% (P = 0.0004)., Conclusions: For men with breast carcinoma, the presence of a family history did not affect the age at presentation, the duration of symptoms, the stage of disease at presentation, or the overall survival. In multivariate analysis, the most powerful predictor of outcome for these men was the status of the axillary lymph nodes., (Copyright 1999 American Cancer Society.)

In the past, various two- and three-dimensional Cartesian, poroelastic finite element formulations have been proposed and demonstrated. Here an axisymmetric formulation of a poroelastic finite element is presented. The intention of this work was to develop a finite element formulation that could easily and efficiently model axisymmetric sound propagation in circular structures having arbitrary, axially dependent radii, and that are lined or filled with elastic porous sound absorbing materials such as foams. The formulation starts from the Biot equations for an elastic porous material expressed explicitly in axisymmetric form. By following a standard finite element development, a u-U formulation results. Procedures for coupling the axisymmetric elements to an adjacent acoustical domain are described, as are the boundary conditions appropriate for unfaced foams. Calculations described here show that the present formulation yields predictions as accurate as a Cartesian, three-dimensional model in much reduced time. Predictions made using the present model are also compared with measurements of sound transmission through cylindrical foam plugs, and the predicted results are shown to agree well with the measurements. Good agreement was also found in the case of sound transmission through a conical foam plug.

Background: We reviewed our image-guided core needle breast biopsy (IGCNBB) experience with patients diagnosed with invasive carcinoma (IC) to determine the accuracy of a core biopsy diagnosis of invasion and our ability to perform a single definitive cancer operation., Methods: All IGCNBBs between July 1993 and July 1997 were reviewed to identify patients diagnosed with IC. Data included initial surgical treatment, surgical pathology, and subsequent surgical treatment., Results: Of the 1,676 biopsies, invasive carcinoma was diagnosed in 208 with follow-up in 204 cases. Invasive carcinoma diagnosis was confirmed in 202 of 204 cases (99%). One hundred ninety-two patients had surgical treatment. Of these 192 patients, 173 (90%) could have achieved definitive surgical treatment with a single operation., Conclusions: An IGCNBB diagnosis of IC is accurate and allows for definitive breast cancer therapy. The potential impact on patient management is that a single operation can usually accomplish what traditionally has required at least two surgical procedures.

Currently, relatively safe, reliable resection techniques are available for most patients with esophageal carcinoma who present with nonmetastatic disease. For optimal results, the surgeon must be familiar with both transhiatal and transthoracic approaches and must individualize the approach depending on the tumor size and location and the patient's functional status. Whereas post-resection survival rates are good for patients with early-stage disease (Stage I or IIa), most patients present with locally advanced, Stage III disease. Although some progress has been made in the past decade in regard to early diagnosis among patients with Barrett's metaplasia undergoing endoscopic surveillance and additional progress has been made in adapting multimodality treatment programs successfully to patients with locally advanced disease, the overall cure rate for patients with esophageal carcinoma remains low.

Purpose: Extrahepatic metastasis represents a frequent pattern of disease progression when fluorodeoxyuridine (FUDR) is given by the intraarterial route for the treatment of unresectable colorectal liver metastases. Systemic fluorouracil (5-FU) plus leucovorin was added to intrahepatic FUDR to prolong the duration of disease control., Methods: Only patients with colorectal cancer who had evidence of unresectable metastases confined to the liver were eligible. Laparotomy was performed to establish arterial perfusion of the liver. Cycles of intrahepatic FUDR followed by a 1-week rest period then intravenous chemotherapy with 5-FU plus leucovorin were administered until maximal regression of hepatic metastases. Maintenance chemotherapy with 5-FU plus leucovorin was then given until disease progression., Results: Fifty-seven patients entered this trial; four patients (7%) were ineligible and 13 (23%) did not receive any chemotherapy on study because of findings at laparotomy. The 40 eligible patients who began chemotherapy are included in the statistical analyses. Twenty-five patients (62% of those who received chemotherapy) experienced regression of liver metastases. The median time to tumor progression was 9 months, but only 3% remained progression-free at 24 months. The median survival duration was 18 months. Toxicity was tolerable with no cases of biliary sclerosis. One treatment-related fatality due to sepsis was observed., Conclusion: Although short-term treatment results appear to be somewhat better than we have previously observed with intrahepatic FUDR alone, the sequential regimen did not have an impact on long-term, progression-free survival in patients with unresectable liver metastases. We are now investigating this regimen as surgical adjuvant therapy in selected patients following hepatic metastasectomy where this aggressive approach might have a greater therapeutic effect in the minimal residual disease setting.

Objective: The goal was to evaluate one institution's experience with image-guided core-needle breast biopsy (IGCNBB) and compare the pathologic results with wire-localized excisional breast biopsy (WLEBB) for patients with positive cores and the mammographic surveillance results for patients with negative cores., Summary Background Data: IGCNBB is becoming a popular, minimally invasive alternative to WLEBB in the evaluation of patients with nonpalpable abnormalities., Methods: This study includes all patients with nonpalpable breast imaging abnormalities evaluated by IGCNBB from July 1993 to February 1997. Patients with positive cores (atypical hyperplasia, carcinoma in situ, or invasive carcinoma) were evaluated by WLEBB. Patients with negative cores (benign histology) were followed with a standard mammographic protocol. IGCNBB results were compared with WLEBB results to determine the sensitivity and specificity for each IGCNBB pathologic diagnosis., Results: Of 1440 IGCNBBs performed during the study period, 1106 were classified as benign, and during surveillance follow-up only a single patient was demonstrated to have a carcinoma in the index part of the breast evaluated by IGCNBB (97.3% sensitivity, 99.7% specificity). IGCNBB demonstrated atypical hyperplasia in 72 patients, 5 of whom refused WLEBB. The remaining 67 patients were evaluated by WLEBB: nonmalignant findings were found in 31, carcinoma in situ was found in 25, and invasive carcinoma was found in 11 (100% sensitivity, 88.8% specificity). IGCNBB demonstrated carcinoma in situ in 84 patients; WLEBB confirmed carcinoma in situ in 54 and invasive carcinoma in 30 (65.4% sensitivity, 97.7% specificity). IGCNBB demonstrated invasive carcinoma in 178 patients. Three were lost to follow-up. On WLEBB, 173 of the remaining 175 had invasive carcinoma; the other 2 patients had carcinoma in situ (80.8% sensitivity, 99.8% specificity)., Conclusions: An IGCNBB that demonstrates atypical hyperplasia or carcinoma in situ requires WLEBB to define the extent of breast pathology. Mammographic surveillance for a patient with a benign IGCNBB is supported by nearly 100% specificity. An IGCNBB diagnosis of invasive carcinoma is also associated with nearly 100% specificity; therefore, these patients can have definitive surgical therapy, including axillary dissection or mastectomy, without waiting for the pathologic results of a WLEBB. Based on the authors' findings, IGCNBB can safely replace WLEBB in evaluating patients with nonpalpable breast abnormalities.

Patients with clinical features of intestinal obstruction without a history of prior laparotomy or physical evidence of a hernia can be a diagnostic challenge. We attempted to evaluate our preoperative diagnostic accuracy, to assess the effectiveness of our diagnostic tools, and to determine the incidence of various causes of intestinal obstruction in this select group. Medical records of all patients admitted to our institution and taken to surgery with a diagnosis of intestinal obstruction from 1975 through 1995 were reviewed. Patients with a history of prior laparotomy, evidence of hernia, or emergent indications for surgery on admission were excluded. The most common cause of intestinal obstruction in this select group of patients was malignancy. The ability to detect malignancy preoperatively is significantly better than the ability to detect benign causes of obstruction (Pearson Chi square = 4.09 with a P value of 0.04). Preoperative detection of malignancy in these patients is critical for optimal treatment planning and counseling for patients and their families.

Background: Stereotactic core needle breast biopsy (SCNBB) is a minimally invasive technique used to sample nonpalpable mammographic abnormalities. The optimal management of atypical ductal hyperplasia (ADH) diagnosed by SCNBB is unknown. We hypothesized that ADH diagnosed by SCNBB should be evaluated by excisional breast biopsy (EBB) because of the risk of identifying carcinoma in association with ADH that would be missed if a diagnostic sampling technique alone was utilized., Methods: To test this hypothesis, a prospective diagnostic protocol was created which called for SCNBB instead of EBB for patients with mammographic abnormalities considered suspicious for malignancy. If ADH was noted on histologic evaluation of the cores, patients were advised to undergo an EBB., Results: A review of the initial 900 patients evaluated by SCNBB yielded 39 patients (4.3%) with ADH detected by SCNBB. Thirty-six of these 39 patients agreed to proceed with EBB: 19 patients demonstrated benign findings including atypical ductal hyperplasia, 13 patients demonstrated noninvasive ductal carcinoma, and 4 patients had evidence of invasive carcinoma., Conclusions: A 47% rate of detecting noninvasive or invasive breast carcinoma supports the hypothesis that ADH detected by a sampling technique, such as SCNBB, should be managed by EBB.

Objective: To examine trends for use of transhiatal esophagectomy (THE) and to relate outcome variables to changes in use, controlling for preoperative risk., Background: High operative morbidity and mortality rates are reported with conventional transthoracic esophagectomy (TTE). Transhiatal esophagectomy has been proposed as an alternative but is controversial., Methods: In this retrospective study divided into early and late time periods, outcome variables were subjected to univariate and multivariate analyses., Results: Use of THE increased significantly in the late period (p < 0.0001). Patients who had THE had significantly higher American Society of Anesthesiologists (ASA) risk scores (p < 0.001). By the late period, 92% of patients with ASA III/IV scores were resected by THE. Postoperative morbidity decreased significantly and operative mortality decreased from 15% to 0% (p < 0.01) between the early and late time periods. By multivariate analysis, ASA > or = III and TTE were associated with adverse surgical outcome. Pathologic stage determined disease-free survival, which was 37% at 3 years for all survivors., Conclusions: Increased use of THE results in better operative outcome and does not adversely affect disease-free survival.

Pelvic recurrence from colorectal cancer produces significant morbidity. Radiation can help palliate the pain produced by this recurrence. Frequently patients with recurrent colorectal cancer will progress to a constant unrelenting pain and obstructive uropathy with sacral and bladder involvement. These patients can be candidates for an aggressive surgical resection with the hope of significant palliation and prolonged survival. From October 1988 to December 1991, six patients had total pelvic exenteration at our institution. Of these six patients, two had en bloc sacral resection at levels S1-S2 and one at S2-S3. Two patients had residual disease at the time of primary surgery, and in the other four patients, recurrence occurred 7 to 48 months after primary resection. One patient died with disease at 7 months, and five patients are alive at 9, 25, 25, 37, and 37 months since the pelvic resection; four have no evidence of disease. The present Karnofsky performance status is 80% or greater in all patients. There were no operative deaths. Of the five living patients, the survival from diagnosis of the primary lesion is 25 to 97 months. Total pelvic exenteration and abdomino-sacral exenteration can produce significant palliation and prolong survival in a selected group of patients with pelvic recurrence from colorectal cancer.

Breast conservation therapy is an accepted treatment option for early stage breast carcinoma, but is rarely considered appropriate for locally advanced nonmetastatic lesions. Mastectomy specimens of 46/50 patients treated at the Ochsner Clinic and the Mallinckrodt Institute of Radiology with neoadjuvant chemotherapy prior to mastectomy +/- irradiation were evaluated by a single pathologist to assess tumor response to chemotherapy. Forty percent of this group would potentially have been eligible for breast conservation therapy, using a residual tumor size of < or = 4 cm with negative surgical margins as the criteria. Patients most likely to qualify for breast conservation therapy were those with T3N0-1 lesions (67%). Least likely were patients with skin involvement at diagnosis 4/33 (12%). Tumors with an extensive intraductal component at biopsy often had residual islands of intraductal carcinoma occupying the original tumor volume, even when the invasive component was absent or much reduced. A prospective trial will be required to determine whether or not acceptable local control rates can be obtained after breast conservation therapy for that subset of patients with a favorable response to induction chemotherapy.

From January 1981 to December 1990, 55 consecutive patients underwent esophageal resection by either the transhiatal (THE, 26 patients) or transthoracic (TTE, 29 patients) approach. Patient age, tumor size, and tumor stage were similar in the two groups. THE patients had a significantly worse mean preoperative American Society of Anesthesiologists (ASA) risk class assigned by the anesthesiologist. Patients who underwent THE had a significantly lower operative mortality and rate of cardiopulmonary complications, significantly shorter intensive care unit and hospital length of stay, and a significantly better postoperative survival when operative deaths are included in the analysis. Operative deaths in the TTE group were concentrated among patients > 65 years of age (4 of 9 died), in an ASA risk class > or = III (3 of 7 died) or with moderate or severe cardiac or pulmonary impairment preoperatively (4 of 6 died).

Fine needle aspiration (FNA) biopsy in conjunction with ultrasonic definition of nonpalpable masses in the neck region is being used more frequently. Currently available preoperative localization tests have failed, in many instances, to delineate adequately the location of missed adenomas of the parathyroid gland. We describe herein the use of ultrasonically guided FNA of parathyroid tissue with immunoperoxidase confirmation for precise localization of the diseased gland. Three patients with persistent hypercalcemia after exploration of the neck were referred to Ochsner Clinic, New Orleans. In two of these patients, a parathyroid adenoma had been removed, while in one patient no adenoma was found. All patients had elevated calcium (range 10.9 to 11.6 milligrams per deciliter), low phosphorous and elevated parathyroid levels. Preoperative ultrasonography to localize the suspected parathyroid glands was performed, with FNA and immunohistochemical confirmation. Smears confirmed adequate cellular material. Alcohol fixed, Papanicolaou stained and air dried, Wright's and Giemsa stained smears were evaluated for the presence of parathyroid cells by conventional cytologic examination. The Papanicolaou-stained slides were then decolorized in 1 percent hydrochloric acid in 70 percent ethanol. After decolorization, the smears were stained for parathyroid hormone (PTH) in an avidin-biotin complex (ABC) system, using a commercially available ABC kit (Vector Laboratories Inc.). The primary antibody is a polyclonal antiserum generated in rabbits against a synthetic human PTH. Negative controls were obtained from normal thyroid glands. In all three patients, the diseased gland was localized by ultrasound with cytologic and immunohistochemical confirmation, one on the right side and two on the left side. At surgical excision, the adenomas weighed 0.8 and 0.75 gram and the carcinoma, 0.75 gram. In two, intraoperative identification of the diseased gland was aided by ultrasound directed methylene blue injection into the adenoma. During a follow-up evaluation of eight to 24 months, serum calcium had remained normal in two patients, and one patient had become hypocalcemic and required calcium supplements. The preoperative localization allowed a direct surgical approach to the side in question in all patients. Ultrasonically guided FNA in an immunoperoxidase system can be a valuable preoperative localization technique for patients with recurrent hyperparathyroidism, thus avoiding extensive exploration of the neck with the subsequent complications.

Breast preservation has been shown to be a good alternative to mastectomy in selected patients with breast cancer. The purpose of this study was to evaluate the characteristics of cancer developing in the opposite breast to determine if breast preservation should be attempted in that breast as well. From 1979 to 1988, 172 women underwent tylectomy, axillary dissection and irradiation for carcinoma of the breast. All had follow-up mammogram. Mean age was 55 years. Mean follow-up time was 50 months. Thirteen patients (7.6%) developed cancer in the opposite breast. Three cancers were carcinoma in situ, nine were stage I, and one was stage IIa. Nine of 13 patients had breast preservation therapy, and four had mastectomies. Ten patients are alive with no evidence of disease, two are alive with disease and one died with disease. Breast preservation for bilateral breast cancer is a safe alternative if patients can be followed closely.

Mammographic changes after lumpectomy, axillary dissection and irradiation are common and unpredictable. To study the significance of these changes at the first follow-up mammogram, we retrospectively reviewed reports of 172 women treated in this manner between 1979 and 1988. The mean follow-up time was 50 months. Eight patients had recurrences in the same breast, while 13 patients had carcinoma develop in the opposite breast. The mean time of follow-up mammograms was 11 months (range of one to 48 months). Twenty-six patients had a normal mammogram, while 146 patients had some changes within the irradiated breast. Thirty-one patients had suspicious findings--a mass, speculation or new microcalcifications. None of these 31 patients had carcinoma confirmed by biopsy or follow-up examination. Of eight patients with recurrence in the same breast, six had a biopsy because of findings on physical examination, while two had changes from previous mammograms. The mean time to recurrence was 50 months (range of 24 to 81 months). We conclude that mammographic changes in the irradiated breast are common after lumpectomy and irradiation for carcinoma of the breast. A baseline mammogram should be done six months after irradiation is completed. Changes that occur at this time should be considered secondary to surgical treatment and irradiation and are not an indication for immediate biopsy. These findings should be reconfirmed by a mammogram performed one year after irradiation to prove that these changes are stable. Physical examination and yearly mammography of both breasts are imperative in the follow-up evaluation of patients treated in this manner.

Aneurysms of the celiac artery are unusual lesions and account for only 4% of all splanchnic aneurysms. In recent years, the incidence has been noted to rise because of the increased use of sonography, computerized tomography, and arteriography. Although patients are often asymptomatic at the time of diagnosis, the risk of rupture is high; therefore, surgical resection should be undertaken in acceptable candidates. We report the case of a large celiac artery aneurysm treated with distal pancreatectomy and celiac artery aneurysmectomy.

A carotid body tumor is a paraganglioma of the carotid bifurcation. Histologic appearance does not correlate with the malignant potential of the lesion, and thus a reliable prognostic marker for these tumors is lacking. To determine whether flow cytometric analysis of paraffin block specimens by DNA index and synthetic phase fraction (SPF) would be of prognostic value, a retrospective chart review of 14 patients with carotid body tumors was performed. Three of 14 tumors were aneuploid and were the only tumors with SPF greater than 15%. One of 3 patients (33%) with an aneuploid tumor (SPF = 22%) developed a local recurrence; no patient with a diploid tumor developed a recurrence. Two of 3 (67%) patients with aneuploid tumors (SPF = 18%) but only 1 of 11 (9%) with a diploid tumor were symptomatic preoperatively (P = 0.03). DNA index and SPF may help select a subgroup of patients with more aggressive tumors who are at increased risk for recurrence and therefore require closer follow-up.

This study was conducted to analyze the effect of different doses of cyclophosphamide (CY) on the lymphocyte populations in the rat. Monoclonal antibodies against rat determinants were used: W3/13 (T lymphocytes), W3/25 (T helper), OX-8 (non-helper), and OX-33 (B lymphocytes). Blood samples were collected on days 0, 3, 7, and 14 from four groups of F-344 Fisher rats (n = 4): three that received 25, 50, or 75 mg/kg of CY and a control group. The duration and severity of lymphocyte depletion were dose-related and were evident for both helper and non-helper cells (p less than 0.02). The helper-to-non-helper ratio increased for the group that received 25 mg/kg when compared with control and other groups, but was only significantly changed when compared with the 75 mg/kg group (p = 0.004). This effect was transitory and was only seen on day 3. The control and the 25 mg/kg groups gained weight; the other two groups lost weight (p less than 0.05). Lower doses of CY were associated with a transitory immunostimulatory effect and no morbidity when compared with higher doses.

Although fine needle aspiration (FNA) of thyroid masses has been performed since the 1950s, only recently has it become a common method of diagnosing thyroid malignancy. To assess the trends in thyroid surgery during the last 38 years at this institution, a retrospective study of the total number of cases during 2-year periods of each decade were reviewed, yielding 509 cases. Results showed that the total number of cases and the type of surgical procedure remained stable until recent years when FNA was more commonly used. For the 1987-1988 period, the total number of cases decreased (from an average of 112 per period in 1950-1981 to 60 in 1987-1988), but the percentage of cases with carcinoma was markedly increased (from 6.3% in 1950-51 to 46.7% in 1987-88). The percentage of total thyroidectomies performed increased due to a preoperative pathological diagnosis afforded by FNA. A decrease in surgical complications was also seen (from an average of 4.5% per period in 1950-1981 to 1.6% in 1987-1988). FNA has been shown to reduce the number of patients requiring surgery, increase the percentage of carcinoma in operative cases, increase the number of total thyroidectomies, and increase the percentage of preoperative pathologic diagnoses.

Neutropenic enterocolitis is a symptom complex of fever, abdominal pain, distention, nausea, vomiting, diarrhea, and bloody stools occurring in a patient with a low neutrophil count and is most often seen in patients with acute leukemia after a course of chemotherapy. In most cases, neutropenic enterocolitis is a self-limited condition, but complications of transmural intestinal necrosis and bowel perforation may occur in a small number of patients. Surgical management should be reserved for those patients with bowel wall necrosis or perforation; however, early identification of these patients is difficult. We report our experience with the use of diagnostic peritoneal lavage in three patients with the symptoms and signs of neutropenic enterocolitis. In each case, Gram's stain of lavage fluid revealed no evidence of polymicrobial contamination of the peritoneal cavity. All three patients were managed medically, with resolution of their abdominal symptoms. Peritoneal lavage is helpful in excluding bowel perforation and avoiding unnecessary surgical intervention in patients with neutropenic enterocolitis.

Thymomas are the most common anterior mediastinal masses. Malignant potential and prognosis are unrelated to histologic appearance. Deoxyribonucleic acid (DNA) flow cytometry is of prognostic significance in a variety of tumors. We reviewed the records of 35 patients who on pathologic examination had a thymoma or thymic carcinoma. Flow cytometric studies, including DNA indices (ploidy) and S phase fraction, were done on paraffin block specimens from 31 patients. We believe this is the first report of DNA flow cytometric studies in thymic pathology. Mean survival was 63.5 +/- 13.3 months for patients with benign thymomas, 10.5 +/- 4.6 months for patients with malignant thymomas, and 19.3 +/- 4.1 months for patients with thymic carcinomas. Patients with benign thymomas lived significantly longer than those with malignant thymomas (P = .001) and thymic carcinomas (P = .03). DNA flow cytometry demonstrated four aneuploid tumors (two benign thymomas and two malignant thymomas). All thymic carcinomas were diploid. There was no statistically significant difference among the groups. The mean S phase fraction was 15.22% for benign thymomas, 11.15% for malignant thymomas, and 14.31% for thymic carcinomas. No statistically significant difference was found among the groups. We conclude that flow cytometry is not a useful guide to malignant potential or prognosis in thymomas and thymic carcinomas.

While hepatic resection of metastatic colorectal carcinoma is accepted as effective in selected patients, resection of metastases to other solid organs has not gained wide acceptance. We retrospectively reviewed the records of 49 patients who had resection of isolated pulmonary (18 patients) and hepatic (31 patients) metastases from the large bowel, comparing disease-free survival and overall survival. Tumor parameters analyzed included Dukes' stage, deoxyribonucleic acid (DNA) flow cytometry, and number of metastases. Dukes' B and diploid tumors had longer disease-free survival and overall survival than did Dukes' C and aneuploid tumors, though the difference was not significant. Patients with a single lung metastasis had a significantly longer disease-free survival (P = .02) than did patients with multiple metastases. Mean and median survival were longer in patients with lung metastases. Five-year actuarial survival was 19% for patients with liver metastases and 47% for patients with lung metastases. Resection of isolated pulmonary metastases from the large intestine results in survival comparable to or better than resection of hepatic metastases. An aggressive surgical approach is warranted in patients with isolated resectable pulmonary metastases of colorectal carcinoma.

Forty-four consecutive stricture repairs by one surgeon with long-term follow-up study are reported. Sutured anastomoses were performed in 39 patients. Essentials of the sutured repair include minimal dissection of the proximal duct, a one-layer anastomosis, mucosa-to-mucosa apposition, and a preference for hepaticojejunostomy with a T-tube stent. Eighty-six per cent of the patients treated by this technique achieved satisfactory results. This technique is the procedure of choice for repair of biliary stricture.

In dogs with appendicitis-peritonitis, intraperitoneal povidone-iodine caused death more rapidly than the instillation of saline solution. The bacterial content of canine peritoneal fluid increased with time. Although fewer bacteria were found in fluid from povidone-iodine-treated dogs, the differences were not statistically significant. Qualitative chemical analysis of peritoneal fluid revealed iodide, but not free iodine, 15 to 30 minutes after instillation of povidone-iodine. Iodine was present in the peritoneum at 2 hours but not at 3 or 6 hours. The antibacterial effect of povidone-iodine was demonstrated in mice challenged intraperitoneally with lethal doses of Escherichia coli. Povidone-iodine diminished mortality when injected immediately (p less than 0.005) but not when given 1 to 3 hours later. Immediate injection of povidone-iodine into mice lowered the number of E. coli by 3 logs. Injection of povidone-iodine 3 hours after bacterial challenge lowered the number of E. coli by only 1/3 log. This lesser bactericidal effect in mice is attributed to greater dispersal and sequestration of bacteria throughout the peritoneal cavity with time and with inactivation of povidone-iodine by reduction to iodide in vivo. In dogs with appendicitis-peritonitis, the more rapid death after treatment with povidone-iodine was not associated with differences in peritoneal microflora but with peritoneal absorption of excessive amounts of iodide.

Thirty-five consecutive cases of adenocarcinoma of the ampulla of Vater seen over the past 36 years were reviewed. The introduction of new diagnostic techniques over the course of this study improved the accuracy of preoperative diagnosis but did not lead to earlier diagnosis. The surgical resectability rate was 88%, and 53% of postoperative survivors were free of disease at 5 years. Of the 14 patients with metastases to regional lymph nodes, 27% survived disease-free for 5 years. Surgical mortality was 25% for the entire series but has been reduced to 6.6% over the past decade. Surgical mortality was primarily due to leakage of the pancreaticojejunostomy; the risk of pancreaticojejunostomy leak correlated inversely with the degree of chronic pancreatitis in the pancreatic remnant. In 35% of resected cases, a benign adenomatous component was contained within the cancer of the ampulla of Vater. Cure rates are good for this lesion. The most important factor in maximizing cure rate is careful attention to the technical details of pancreaticojejunostomy in order to minimize surgical mortality. Benign adenomas appear to be a frequent precursor of carcinoma of the ampulla of Vater.

We report the clinical and radiologic findings and course of two patients who developed drug-related biliary sclerosis during hepatic artery infusion of floxuridine. If severe and persistent jaundice develops during the course of regional hepatic infusion of floxuridine, and obstructive component in the biliary tree must be suspected and investigated by endoscopic retrograde cholangiography. Regional infusion therapy should be stopped immediately. Surgical treatment of the obstructing lesion is avoided unless cholangitis occurs or jaundice persists for more than 3 months and a surgically correctable lesion exists.

The surgeon's responsibility to patients with colorectal cancer does not end with resection of the primary locoregional disease. The surgeon has a role to play in (1) designing and implementing strategies aimed at preventing recurrence, (2) early detection of recurrent disease, and (3) resective therapy of recurrent disease in selected instances, either with curative intent or for palliation. To perform these roles, the surgeon must have a thorough knowledge of catheter techniques for regional drug delivery, resective techniques for metastatic or locally recurrent disease, and combined surgical and radiotherapy approaches.

A description of our current approach to management of benign biliary strictures is presented with emphasis on the importance of preservation of ductal blood supply during reconstruction. Although we have repeatedly stressed the primary importance of prevention of these injuries by a carefully performed cholecystectomy, the frequency with which cholecystectomy is carried out will undoubtedly result in an ongoing small number of such serious injuries. Therefore, continued refinement of the technique of biliary reconstruction and careful evaluation of results are important.

Two experimental models were utilized to study the efficacy of intraperitoneal povidone-iodine in an established peritonitis. In both models, there was a 100% mortality in the povidone-iodine treated group. In laboratories which have reported favorable results, the animals were treated before peritonitis was allowed to develop. Clinical studies with povidone-iodine lavage have used dilute solutions which did not remain in the infected space. The effectiveness of this method was probably due to mechanical continuous irrigation. Our toxicity studies showed povidone-iodine to be fatal in normal animals in dosages exceeding 4.0 ml/kg. However, a dose of 2.0 ml/kg, which was nontoxic in normal animals, was fatal in animals with peritonitis. This study strongly suggests that the intraperitoneal administration of povidone-iodine can be fatal when the animal is compromised by peritonitis. The mechanism of this effect is unclear. On the basis of these studies, the intraperitoneal administration of povidone-iodine cannot be recommended for therapy of peritonitis.

The presentation, treatment, and outcome of 12 patients with high-grade neurogenic sarcoma (NS) of the extremity were compared with those of 21 patients with high-grade extremity soft-tissue sarcoma of nonneural origin in a retrospective study from January 1976 to January 1988. Pain and neurologic deficit were more common in the NS group. Limb-sparing surgery was carried out with equal frequency in both groups. Local recurrence was six times more frequent in the NS group at three-year follow-up (59% vs 10%). Width of resection margin was the dominant prognostic variable bearing on local control after limb-sparing surgery. Anatomic and functional constraints tended to limit resection margin in patients with NS arising from mixed motor-sensory or predominantly motor nerves.