Metabolites of purine nucleoside phosphorylase (NP) in serum have the potential to delineate pancreatic adenocarcinoma.

Pancreatic Adenocarcinoma (PDAC), the fourth highest cause of cancer related deaths in the United States, has the most aggressive presentation resulting in a very short median survival time for the affected patients. Early detection of PDAC is confounded by lack of specific markers that has motivated the use of high throughput molecular approaches to delineate potential biomarkers. To pursue identification of a distinct marker, this study profiled the secretory proteome in 16 PDAC, 2 carcinoma in situ (CIS) and 7 benign patients using label-free mass spectrometry coupled to 1D-SDS-PAGE and Strong Cation-Exchange Chromatography (SCX). A total of 431 proteins were detected of which 56 were found to be significantly elevated in PDAC. Included in this differential set were Parkinson disease autosomal recessive, early onset 7 (PARK 7) and Alpha Synuclein (aSyn), both of which are known to be pathognomonic to Parkinson's disease as well as metabolic enzymes like Purine Nucleoside Phosphorylase (NP) which has been exploited as therapeutic target in cancers. Tissue Microarray analysis confirmed higher expression of aSyn and NP in ductal epithelia of pancreatic tumors compared to benign ducts. Furthermore, extent of both aSyn and NP staining positively correlated with tumor stage and perineural invasion while their intensity of staining correlated with the existence of metastatic lesions in the PDAC tissues. From the biomarker perspective, NP protein levels were higher in PDAC sera and furthermore serum levels of its downstream metabolites guanosine and adenosine were able to distinguish PDAC from benign in an unsupervised hierarchical classification model. Overall, this study for the first time describes elevated levels of aSyn in PDAC as well as highlights the potential of evaluating NP protein expression and levels of its downstream metabolites to develop a multiplex panel for non-invasive detection of PDAC.

Effect of a genetic deficiency of terminal deoxynucleotidyl transferase on autoantibody production by C57BL6 Fas(lpr) mice.

Terminal deoxynucleotidyl transferase (TdT) adds nontemplate coded nucleotides (N additions) between the recombining ends of immunoglobulin and T cell receptor genes. These nucleotides add significant diversity to the Ig and TCR repertoires. Amino acids coded for by these nucleotides play a key role in the binding of self antigens by autoantibodies and autoreactive T cells. To determine the effect of a lack of N additions on autoantibody production, we bred the TdT knockout genotype onto the autoimmune C57BL/6-Fas(lpr) background. TdT-deficient mice had significantly lower sera anti-DNA and rheumatoid factor activity than their TdT-producing littermates. C57BL/6-Fas(lpr) TdT-deficient mice had shorter VH CDR3 regions and fewer VH CDR3 arginines [0.6% versus 4. 7%] than their TdT-producing littermates. These data indicate that the absence of TdT limited the production of anti-DNA antibodies and rheumatoid factors in C57BL/6-Fas(lpr) mice, likely due to constraints on Ig diversity secondary to the lack of TdT-derived N additions.

Color Doppler sonographic detection of tumor flow in superficial melanoma metastases: histologic correlation.

Color Doppler sonographic detection of tumor flow within superficial melanoma metastases was investigated to determine if tumor size, vessel size, or vessel number influences signal detection. Color Doppler imaging of 32 pathologically proved melanoma metastases was performed at 6 MHz with color Doppler imaging parameters optimized for each lesion scanned. All lesions were measured in three dimensions and the presence or absence of internal flow was documented. Seven surgically excised metastases underwent immunohistochemical staining for endothelial markers. Internal flow was detected in 21 of 32 masses and was completely absent in 11. In comparison to all masses without flow, the masses with flow had significantly greater anteroposterior dimensions (P < 0.00036) and volumes (P < 0.01). Histologically, mean vessel diameter in masses with flow was significantly greater (P < 0.05) than in those without flow, but mean vessel number was not significantly different. In conclusion, detectability of tumor blood flow in superficial melanoma metastasis may be related more to tumor size and vessel size than vessel number. Failure to detect color signal within a superficial melanoma mass does not indicate a lack of internal vascularity.

Superficial melanoma metastases: appearances on gray-scale and color Doppler sonography.

OBJECTIVE: The purpose of this study was to describe the sonographic appearances of melanoma metastases of the skin, subcutaneous tissues, and superficial lymph nodes. MATERIALS AND METHODS: Gray-scale sonography was performed on 31 superficial melanoma metastases in 18 patients. Discreteness of borders, contours, echogenicity, echotexture, and degree of acoustic through-transmission were evaluated for each lesion. Color Doppler sonography was also performed on 25 of the 31 lesions, by which the amount of internal color flow was qualitatively assessed. RESULTS: Twenty-eight (90%) of the 31 metastases had well-defined borders. Contours were smooth in 17 (55%), lobulated in 12 (39%), and spiculated in two (6%). Nineteen metastases (61%) were hypoechoic to muscle, 10 (32%) were isoechoic, and two (6%) were hyperechoic. Echotexture was homogeneous in six lesions (19%), mildly heterogeneous in 13 (42%), moderately heterogeneous in 11 (35%), and markedly heterogeneous in one (3%). Twenty-two lesions (71%) showed enhanced acoustic through-transmission. Of the 25 melanoma metastases for which we performed color Doppler sonography, 18 (72%) had internal arterial color flow and seven (28%) did not. The flow was characterized as mild in 13 (72%) of 18, moderate in four (22%), and marked in one (6%). CONCLUSION: On sonography, superficial melanoma metastases typically are well-defined hypoechoic lesions with smooth or lobulated contours, mild to moderate heterogeneity, and enhanced acoustic through-transmission. Internal flow revealed by color Doppler sonography is present in many, but not all, superficial melanoma metastases.

Superficial soft-tissue masses suggestive of recurrent malignancy: sonographic localization and biopsy.

OBJECTIVE: We investigated the usefulness of high-resolution sonography to localize superficial soft-tissue masses and to guide needle sampling for recurrent malignancy. MATERIALS AND METHODS: High-resolution sonography (10-MHz) was used to locate and guide needle sampling of 16 palpable and eight impalpable superficial masses suggestive of recurrent malignancy in 23 patient (12 men, 11 women; 34-85 years old). After detection, 22 (92%) of the masses were immediately sampled by fine-needle aspiration with 18- to 25-gauge needles and two (8%) were sampled by a 20-gauge core gun. RESULTS: Diagnostic material was obtained without complication from all 24 masses and proved positive for recurrent disease in 13 (54%). Ten (63%) of 16 palpable and three (38%) of eight impalpable masses proved positive for recurrent malignancies. One third of superficial soft-tissue masses were detected by imaging only, and of the masses not revealed on imaging, three (23%) of 13 were the site of first recurrence. Most nonnodal superficial masses (8/13) were benign, unlike the lymph nodes, of which three (27%) of 11 were benign. CONCLUSION: Not all early recurrent malignancies within the skin and subcutaneous tissues are detected by clinical examination. High-resolution sonography provided us with a rapid, safe, and accurate means of localizing and then guiding needle biopsies of superficial soft-tissue masses suggestive of recurrent malignancy.

Clinical and serologic manifestations of autoimmune disease in MRL-lpr/lpr mice lacking nitric oxide synthase type 2.

Nitric oxide (NO) is an important mediator of the inflammatory response. MRL-lpr/lpr mice overexpress inducible nitric oxide synthase (NOS2) and overproduce NO in parallel with the development of an autoimmune syndrome with a variety of inflammatory manifestations. In previous studies, we showed that inhibiting NO production with the nonselective nitric oxide synthase (NOS) inhibitor NG-monomethyl-arginine reduced glomerulonephritis, arthritis, and vasculitis in MRL-lpr/lpr mice. To define further the role of NO and NOS2 in disease in MRL-lpr/lpr mice, mice with targeted disruption of NOS2 were produced by homologous recombination and bred to MRL-lpr/lpr mice to the N4 generation. MRL-lpr/lpr littermates homozygous for disrupted NOS2 (-/-), heterozygous for disrupted NOS2 (+/-), or wildtype (+/+) were derived for this study. Measures of NO production were markedly decreased in the MRL-lpr/lpr (-/-) mice compared with MRL-lpr/lpr (+/+) mice, with intermediate production by the MRL-lpr/lpr (+/-) mice. There was no detectable NOS2 protein by immunoblot analysis of the spleen, liver, kidney, and peritoneal macrophages of the (-/-) animals, whereas that of (+/+) was high and (+/-) intermediate. The (-/-) mice developed glomerular and synovial pathology similar to that of the (+/-) and (+/+) mice. However, (-/-) mice and (+/-) mice had significantly less vasculitis of medium-sized renal vessels than (+/+) mice. IgG rheumatoid factor levels were significantly lower in the (-/-) mice as compared with (+/+) mice, but levels of anti-DNA antibodies were comparable in all groups. Our findings show that NO derived from NOS2 has a variable impact on disease manifestations in MRL-lpr/lpr mice, suggesting heterogeneity in disease mechanisms.

Endoluminal sonographic evaluation of ureteral and renal pelvic neoplasms.

The objective of this study was to demonstrate the feasibility of endoluminal ultrasonography as an adjunct to endoscopy for the evaluation of urothelial neoplasms. An endoluminal ultrasound system using a 12.5 or 20 MHz transducer housed in a 6.2 French catheter was used intraureterally in 38 patients being evaluated endoscopically for suspected tumors in the renal pelvis or ureter. The ultrasonographic, endoscopic, and pathologic findings were evaluated. The location, size, and sonographic characteristics of the tumors in the upper urinary tract were well demonstrated. The information obtained by this technique can be used to guide endoscopic biopsy and laser ablation of the tumor. Endoluminal ultrasonography also has proved helpful in defining the location of a tumor relative to an adjacent vessel and in identifying crossing vessels that cause extrinsic filling defects in the ureter. In a few pathologically correlated cases, endoluminal ultrasonography was accurate in assessing invasion. We have evaluated successfully a variety of non-neoplastic filling defects in relatively few cases. Determination of the eventual usefulness of this technique awaits greater clinical experience and large clinical trials.

Transrectal ultrasound-guided biopsy causes hematogenous dissemination of prostate cells as determined by RT-PCR.

OBJECTIVES: To determine if transrectal ultrasound-guided (TRUS) prostate biopsy causes dissemination of prostate cells into the circulation as assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) targeted against prostate-specific antigen (PSA) mRNA. METHODS: RT-PCR PSA analysis was performed before and after prostatic invasive manipulations in 50 men. The cases consisted of 47 patients with TRUS and 3 with transurethral resection of the prostate (TURP). Peripheral venous blood (8 mL) was drawn before and within 60 minutes after the procedure. Total RNA was extracted from fractionated blood, and RNA/cDNA quality was assured and normalized with beta-actin RT-PCR analysis. The PSA primers hybridize exons 3 and 5, yielding a 254-basepair PCR product. The assay detects one LNCaP cell in a background of 100 million lymphoid cells and a single copy of PSA cDNA on an ethidium bromide gel. RESULTS: Among the 47 TRUS cases, 43 specimens were evaluable. Forty-two cases were negative before biopsy; among these patients, 4 cases (9.5%) converted to a positive RT-PCR PSA result. Both benign and malignant TRUS biopsies were capable of producing a positive RT-PCR PSA signal implicating iatrogenic dissemination of cells. All three TURP cases converted from a negative to a highly intense positive signal. CONCLUSIONS: We conclude that a positive RT-PCR PSA signal may result from release of prostate cells into the peripheral circulation after a TRUS biopsy and TURP. TURP causes greater dissemination than TRUS. Based on these preliminary data, we recommend that future molecular staging studies should be based on blood specimens drawn before performance of TRUS biopsy. This may be an important mechanism of prostate cancer dissemination meriting further investigations.

Color Doppler imaging in predicting the biologic behavior of prostate cancer: correlation with disease-free survival.

OBJECTIVES: We investigated the association of transrectal color Doppler imaging (CDI) signal detection in localized prostate cancer with biologic behavior as assessed by tumor Gleason grade, seminal vesicle invasion, capsular and margin status, and actuarial biochemical freedom from relapse. METHODS: From 1991 to 1996, transrectal ultrasound with CDI and biopsy was performed in 2718 men using a 7.0-MHz probe optimized to detect color-coded blood flow within the gland and along the capsular margin. Color flow was graded on a scale from 0 to 2+, with 0 and 1+ representing no detectable flow and normal flow, and 2+ indicating increased flow. Color flow maps were constructed in 47 men with clinically localized prostate cancer treated by radical prostatectomy (RP) and compared to their whole mount RP specimen step sections. RESULTS: Color flow detected within the index tumor was graded as 2+ in 22 of 47 patients and 0 or 1+ in the remaining 25. Tumors graded 2+ correlated with higher Gleason grade, higher incidence of seminal vesicle invasion, and higher relapse rate, with only 11 of 22 patients disease free based on undetectable prostate-specific antigen (PSA) levels. In contrast, 24 of 25 patients with tumors graded 0 or 1+ are free of biochemical relapse with a median follow-up of 30.9 months. Patients with increased flow were 10.2 times more likely to relapse even after correction for other prognostic variables. In addition, tumors with 2+ capsular flow correlated with a higher incidence of non-organ-confined disease. CONCLUSIONS: Color-coded Doppler flow within the tumor and overlying capsule appears to correlate with both tumor grade and stage, respectively. Detection and grading of color-coded flow within biopsy-proven cancers may identify patients with a high likelihood of biochemical relapse.

Color Doppler sonography of the prostate.

The digital rectal exam (DRE), serum prostate specific antigen (PSA) level and transrectal ultrasound (TRUS) serve as the primary means of early detection of prostate cancer, but all have known limitations. Because of the low predictive value for the gray scale detection of prostate cancer with TRUS, attempts have been made to improve the diagnostic accuracy of TRUS by incorporating color Doppler imaging (CDI) into the standard examination. With CDI, the sonographer has the ability to investigate both normal and abnormal flow within the prostate gland. Recent studies have supported the ability of CDI to detect vascularity in tumors that otherwise were not detectable with conventional gray scale TRUS, which suggests the potential for increase tumor detection. In the following article the rationale behind the use of color Doppler, the normal Doppler features of the prostate gland, and the result of the published studies on the diagnostic accuracy of color Doppler in prostate cancer are analyzed. In addition, areas of future research interest are reviewed.

Effects of training and experience in interpretation of emergency body CT scans.

PURPOSE: To determine the effects of level of training and other factors on the rate of discrepant interpretation of emergency body computed tomographic (CT) scans by trainees and staff radiologists. MATERIALS AND METHODS: Five hundred ninety-eight consecutive emergency CT studies were prospectively interpreted by radiology residents or board-certified body imaging fellows over a 12-month period. Each interpretation was reviewed within 12 hours by an attending body CT radiologist. Major discrepancies between staff radiologists' and trainees' interpretations were defined and those with the potential to affect immediate patient therapy; minor discrepancies were defined ad those without such potential. The effects on discrepancy rates were examined for abnormal versus normal CT findings and trauma versus nontrauma cases. RESULTS: Major and minor discrepancy rates were 1.2% and 6.5%, respectively, between interpretations made by the trainee and the staff radiologist. Overall, fellows demonstrated statistically significantly lower discrepancy rates than did senior of junior residents (5.9%, 13.7%, and 13.3%, respectively). The discrepancy rate was higher when CT findings were abnormal than when they were normal (13.5% vs 2.6%). There were no differences between discrepancy rates for trauma and nontrauma cases. CONCLUSION: Experience appeared to decrease discrepancy rates. Trainees were more likely to miss findings than to read normal scans as abnormal.

Fecal incontinence: transvaginal US evaluation of anatomic causes.

PURPOSE: To evaluate transvaginal ultrasonography (US) as an alternative to transanal US for determining the anatomic cause of fetal incontinence in women. MATERIALS AND METHODS: Transvaginal US of the anal canal was performed in 28 women (aged 27-74 years) with fecal incontinence. A side-fire endorectal probe was inserted into the vagina and directed toward the posterior vaginal wall. RESULTS: The internal anal sphincter (IAS) and external anal sphincter muscles were imaged as independent bands in all 28 patients. The calculated mean thickness of the IAS in patients aged younger than 55 years was not significantly different from that in patients aged older than 55 years (P=.31). Posttraumatic anterior muscle disruptions were detected in 16 women; three also had rectovaginal fistulas. A rectal fistula with abscess was detected in one of 12 patients with intact muscles. All muscle disruptions, fistulas, and abscesses were surgically confirmed. CONCLUSION: Transvaginal US enables determination of the anatomic cause of fecal incontinence, allowing the surgeon to select patients who would benefit form surgical repair.

Endosonographic and color Doppler flow imaging alterations observed within irradiate rectal cancer.

PURPOSE: To correlate the endosonographic and color Doppler flow imaging alterations observed in irradiated rectal cancers with the pathologic features of radiation response, and to evaluate the potential impact of altered blood flow on the integrity of the surgical anastomosis. METHODS AND MATERIALS: Endosonography with color and pulsed wave Doppler was performed on 20 rectal cancer masses before and after high dose preoperative radiation (XRT). Pre- and post-XRT observations included comparing alterations in tumor size, sonographic echotexture, color Doppler flow, and pulsatility indices. Comparisons were made with pathologic findings in the irradiated specimens and with the incidence of anastomotic failure. RESULTS: Compared to pre-XRT observations, irradiated rectal cancers decreased in size and became either mixed in echogenicity with less apparent color Doppler flow (16 of 20) or unchanged in color Doppler flow and echotexture (4 of 20). Those with less flow (16 of 20) were imaged later (mean = 90.2 +/- 12.1 days) than those without change in color Doppler flow (mean = 21.7 +/- 2.7 days). Pathologically, the group of four without change in color Doppler signal had features of acute inflammation which were not observed in 16 of 20 imaged later. Based on pulsatility index measurements, both high and low resistance vessels were detected and confirmed by immunohistochemical staining, and features of postradiation obliterative vasculitis were observed. Only one primary anastomosis in 14 patients with decreased flow failed. CONCLUSIONS: The sonographic and color Doppler flow imaging alterations observed within irradiated rectal cancer correlated with changes of postradiation obliterative vasculitis. The apparent diminished local blood flow within high and low resistance vessels post-XRT did not result in an increased incidence of anastomotic failures.

Malignant melanoma: impact of superficial US on management.

PURPOSE: To evaluate the impact of superficial ultrasonography (US) on clinical management of melanoma. MATERIALS AND METHODS: Superficial US in areas at high risk for local recurrence or nodal metastases was performed in 33 patients with cutaneous melanoma. Impact categories were assigned to each US study (n = 55): category 3, US added information that altered clinical management; category 2, US added information that did not change management; category 1, no added information and management unchanged; category 0, not helpful or was misleading. RESULTS: Twenty-two US studies (40%) were category 3: detection of nonpalpable metastases altered surgical therapy (n = 2), demonstration of pharmacodynamic response to chemotherapy (n = 5), and determination of benignancy or malignancy (n = 15). Nine (16%) were category 2: identification of nonpalpable metastases did not alter management. Twenty-two (40%) were category 1: supported clinical impression of no metastases (n = 18) or helped confirm cutaneous, subcutaneous, or nodal metastases (n = 4). Two (4%) were category 0: missed proved metastases. CONCLUSION: Superficial US affected management of melanoma by allowing detection and characterization of masses, guidance of biopsy, and assessment of pharmacodynamic response.

Sequential penile ultrasound monitoring of patients treated with chronic intracavernous prostaglandin E1.

OBJECTIVES: Clinical outcome studies of prostaglandin E1 (PGE1) have shown a markedly decreased rate of palpable fibrosis and plaque formation. In this prospective study we investigate the potential of this agent to produce subclinical fibrotic changes. METHODS: Real-time high-resolution ultrasound scanning of the corpora was performed using a 7.5 to 10 MHz linear array transducer in 80 men on initiation of treatment with self-administered PGE1 and at quarterly intervals during the course of following (3 to 28 months). The dorsal portion of the penile shaft was scanned in the transverse and sagittal planes from base to glans for a side by side comparison of the cavernosal tissue, evaluating local abnormalities of tissue echogenicity. RESULTS: Palpable lesions were not detected in any men on quarterly follow-up examination. Thirteen (16.5%) men developed new echogenic foci not present on pretreatment scanning at the following locations: proximal corpus cavernosum, subcutaneous tissues, and corpus spongiosum. These changes were observed both as single and multiple lesions ranging in size from 1 to 10 mm. The presence of these findings was independent of the etiology of impotence, dose frequency, and duration of intracavernous therapy. CONCLUSIONS: The significance of these subclinical changes is unknown but their low incidence should be recognized when considering long-term intracavernous therapy.

Ultrasound-guided four quadrant biopsy of the prostate: efficacy in the diagnosis of isoechoic cancer.

Five hundred and eighty men underwent transrectal ultrasound-guided biopsy of the prostate using the four quadrant biopsy (4QB) technique. Four hundred and three men had focal hypoechoic lesions of the peripheral gland but the other 177 men referred because of concern for the presence of cancer had no discrete sonographic lesion. Cancer was found from 4QB in only 32 of these 177 men (18.1%) compared to 158 of the 403 men (39.2%) with focal hypoechoic lesions (P < 0.001). Additional biopsy evidence of cancer was found in contralateral isoechoic (sonographically normal) quadrants in 41 men with focal hypoechoic cancerous lesions. In 17 men with hypoechoic lesions that were biopsy-benign, cancer was found in other isoechoic quadrants. There was no difference between the average Gleason scores of hypoechoic cancers and isoechoic cancers, other than when cancers were incidentally found in men with benign focal hypoechoic lesions. These had significantly lower scores (P = 0.02). Cancer yield in the 177 men without hypoechoic lesions increased as a function of prostate-specific antigen (PSA) level; 11% if PSA < 10ng/ml, 32% if > 20ng/ml. Prostatitis was the most common abnormal biopsy finding in these men. 4QB increases the yield of prostate cancer compared to simple biopsy of hypoechoic lesions and improves knowledge of local disease extent. 4QB is recommended for men with elevated PSA levels but no peripheral gland sonographic abnormality.

Endorectal color and duplex imaging of the normal rectal wall and rectal masses.

This study investigates the ability of endorectal ultrasonography aided by color flow and pulse wave Doppler techniques to identify submucosal arterial plexuses of the normal rectal wall and to detect vessels supplying rectal wall masses. Color flow and pulsed wave Doppler analysis of 62 normal submucosal arterial plexuses and vessels feeding rectal wall masses (one rectal endometriosis and seven rectal cancers) was performed. The color signals from normal submucosal arterial plexuses and the one case of rectal endometriosis were judged to be sparse or decreased in comparison to color signals from rectal cancers. The median and mean P1 values for normal submucosal arterial plexuses were significantly greater than those for the central feeding vessels or small peripheral vessels within rectal masses. Our experience with color and duplex endorectal ultrasonography suggests that different vascular structures exist in normal persons compared to those in rectal wall masses. Pathologically, rectal cancers possess vessels with and without a smooth muscle layer, which may produce the high and low resistance signals identified by pulse Doppler.

Transrectal sonographically guided drainage of deep pelvic abscesses.

OBJECTIVE: As an alternative to traditional surgical transrectal and transgluteal drainage, we have examined the efficacy of transrectal sonographically guided drainage for deep pelvic abscesses not accessible by percutaneous transabdominal or transvaginal routes. SUBJECTS AND METHODS: In nine patients (five males and four females) 5-51 years old, sonography or CT showed pelvic abscesses that were deemed unapproachable by percutaneous transabdominal or transvaginal routes because of interposed bowel (five patients), presacral location (two patients), or inability of the pediatric vagina to accommodate a transvaginal probe (one patient). One patient refused both transvaginal and transgluteal routes in preference to transrectal drainage. IV sedation (adults) or general anesthesia (children) was used for all drainages. A 7.5-MHz end-fire transrectal sonographic probe fitted with a biopsy guide was inserted into the rectum, and the collection was localized. With sonographic guidance, an 18-gauge needle and then a guidewire were advanced into the collection. Then with fluoroscopic guidance, a self-retaining drainage catheter was placed by using the Seldinger technique. RESULTS: All nine collections were successfully accessed and effectively drained without complication. Catheters were removed after 1-24 days (mean, 7 days; median, 5 days) without recurrent abscesses. CONCLUSION: Transrectal sonographically guided drainage of deep pelvic abscesses is a safe, well-tolerated, effective alternative to the more traditional surgical transrectal drainage or transgluteal approach, especially in pelvic abscesses that cannot be safely drained via a percutaneous transabdominal or transvaginal route.