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D J Grignon

Publications and source records attributed to D J Grignon.

At least 73 records · Page 4Linked to original sources
PubMed1996

Pathologic staging of prostate carcinoma. What are the issues?

BACKGROUND: Stage is a significant predictor of outcome for patients with carcinoma of the prostate. The American Joint Committee on Cancer (AJCC) and the International Union Against Cancer (UICC) TNM staging system has gained general favor as the clinical staging system of choice for prostate carcinoma. With an increasing number of publications assessing prognostic markers for patients with carcinoma of the prostate, there is a need for the development of a uniform system of pathologic staging to support the clinical stage. METHODS: The literature related to pathologic prognostic markers for patients with carcinoma of the prostate, particularly with regard to staging, was reviewed. From this, issues important to the development of a pathologic correlate to the AJCC/ UICC TNM system were identified. RESULTS: A number of issues were identified related to the development of a pathologic staging system. For radical prostatectomy specimens some of the more important are whether or not subcategorization is needed in the pathologic classification of T2 tumors, definition and quantification of extraprostatic extension, and the reporting of positive surgical margins. CONCLUSIONS: There is a need for the development of a pathologic equivalent to the AJCC/UICC TNM clinical staging system for prostate carcinoma. Consensus needs to be reached on several important issues prior to the adoption and testing of such a system.

Carcinoma↗
PubMed1996

High levels of tissue inhibitor of metalloproteinase-2 (TIMP-2) expression are associated with poor outcome in invasive bladder cancer.

The matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) have been associated with tumor invasion and metastasis in many human cancers. Immunohistochemical studies were performed on frozen tumor samples from 42 patients with invasive bladder cancer treated by cystectomy with monoclonal antibodies against the Mr 72,000 gelatinase A (MMP-2), Mr 92,000 gelatinase B (MMP-9), and TIMP-2 to evaluate their significance in bladder cancer. Immunoreactivity for the gelatinases was predominantly tumor cell-associated, whereas strong TIMP-2 staining was mostly detected in the stroma. Tumor cells demonstrated moderate to strong reactivity for MMP-2 and MMP-9 in 71 and 71% of cases, respectively, which did not correlate with stage, grade, or outcome. Tumor cells were positive for TIMP-2 in 26 (62%) of 42 cases, and this correlated with a worse outcome (69 versus 25% died of disease; P < 0.05). In 31 (74%) of 42, there was moderate to strong stromal staining for TIMP-2; this also was associated with a poor outcome (65 versus 25% died of cancer; P < 0.05). Tumor basement membrane (BM) status was investigated using an antibody to type IV collagen. In 9 cases, the invasive tumor nests were surrounded by an intact BM; in 7 of these, stromal staining for TIMP-2 was absent. None of these 9 patients (0%) died of tumors compared with 7 (100%) of 7 with complete loss of BM staining (P < 0.001). These results suggest a potential role for TIMP-2 and BM staining as prognostic indicators in invasive bladder cancer.

Adult↗
PubMed1996

Differential growth factor responses of epithelial cell cultures derived from normal human prostate, benign prostatic hyperplasia, and primary prostate carcinoma.

Because of a lack of information of the optimum nutritional requirements, epithelial cells derived from normal human prostate and prostate tumors have been difficult to propagate in vitro, which hinders research in prostate carcinogenesis. In an effort to establish optimum nutritional conditions and differences in growth characteristics of normal human prostate (NP), benign prostatic hyperplasia (BPH), and prostatic carcinoma (PCA), we have compared the effects of several growth factors on cell proliferation and elucidated growth properties of low passage epithelial cells derived from NP, BPH, and PCA of an African-American patient. Primary and low passage cultures were propagated in serum-free keratinocyte basal medium (KBM) supplemented with insulin (5 micrograms/ml), hydrocortisone (0.5 microgram/ml), epidermal growth factor (EGF, 10 ng/ml), bovine pituitary extract (BPE; 50 micrograms/ml), cholera toxin (10 ng/ml), and antibiotics. Almost all NP, BPH, and PCA cells were positive for cytokeratins and prostate-specific antigen (PSA). The NP, BPH, and PCA cells were essentially diploid and lacked mutations in c-K-ras and c-Ha-ras oncogenes, and p53 tumor suppressor gene. However, they exhibited progressively accelerating growth parameters. The population doubling times of NP, BPH and PCA were 51 hr, 37 hr, and 29 hr, respectively; their saturation densities were 2.9 x 10(4)/cm2, 3.3 x 10(4)/cm2, and 7.2 x 10(4)/cm2, respectively. The NP and BPH cells required all of the growth factors in the medium, as deletion of any one of the above factors strongly inhibited their growth. The PCA cells, however, were independent of EGF and hydrocortisone. PC-3, an established human prostate cancer cell line, was independent of the growth factors tested. Fetal bovine serum (FBS) inhibited the growth of NP, BPH and PCA cells. In contrast, FBS stimulated the growth of the PC-3 cells in a concentration-dependent manner. These results indicate that in the absence of any apparent karyotype alterations and mutations in c-K-ras, c-Ha-ras and p53 genes, epithelial cells derived from NP, BPH, and PCA exhibit significant differences in their growth properties and responses to growth factors. These variations may represent early changes involved in prostate cancer, while gene mutations and cytogenetic alterations occur in advanced and/or metastatic tumors.

Black or African American↗
PubMed1996

Glutathione S-transferase and multidrug-resistant phenotype in transitional cell carcinoma of the bladder.

OBJECTIVE: To asses the role of expression of resistance phenotypes in treatment failure in patients with invasive transitional cell carcinoma of the urinary bladder, since P-glycoprotein and glutathione S-transferase pi (GST) expression are implicated in resistance to various chemotherapy agents in different tumors. METHODS: Tumor samples from P-glycoprotein and GST-pi were analyzed by immunohistochemistry. RESULTS: P-glycoprotein and GST-pi were found in 35.7 and 42.9% of the samples, respectively. In 21.4% of the samples there was simultaneous expression of both proteins. No significant impact on prediction of tumor behavior was evident on statistical analysis by any one of the protein expressions. CONCLUSION: Drug resistance in transitional cell carcinoma may be through different mechanisms. Although the small sample size of this study precludes firm conclusions, the assessment of P-glycoprotein or GST-pi expression appears to be of little value as a predictor of response to chemotherapy in this group of tumors.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1996

Age and racial distribution of prostatic intraepithelial neoplasia.

AIMS: To study the prevalence, extent and evolution of high-grade prostatic intraepithelial neoplasia (HGPIN) in African-American and Caucasian men of a wide age range in order to help clarify the role this lesion may play in the racial differences of prostate cancer. METHODS: The lesion was documented in step-sectioned, entirely submitted prostates of two study populations: 525 autopsied men who died of trauma and 1,000 patients who had retropubic radical prostatectomy for clinically localized carcinoma of the prostate. RESULTS: We found that HGPIN starts in young individuals and increases progressively with advancing age in both races but is more prevalent in African-Americans. Additionally, the more extensive form of HGPIN with multifocal or diffuse involvement of the gland appears at a younger age in African-Americans. CONCLUSIONS: Microscopic foci of HGPIN can be documented in males in the 3rd and 4th decades with the lesion becoming more extensive in older men. The finding that HGPIN is both more prevalent and its more diffuse form appears earlier in African-Americans, indicates a potentially important role for this lesion in the race-related discrepancies associated with this disease.

Adult↗
PubMed1996

Atypical adenomatous hyperplasia of the prostate: a critical review.

AIMS: The aim of this report is to review the literature concerning atypical adenomatous hyperplasia (AAH) with specific regard to evidence in support of or refuting its role as a precursor lesion for prostatic adenocarcinoma. METHODS: The available literature was collected and critically reviewed. In addition, recently reported (abstract) but as yet unpublished data were included. Particular attention was focused on biological studies. RESULTS: There is considerable morphologic evidence suggesting that AAH is associated with low-grade (Gleason patterns 1 and 2) adenocarcinoma arising in the transition zone. Only limited biologic studies have been performed. There is weak and limited data to indicate that AAH has a proliferation rate higher than hyperplasia but lower than adenocarcinoma. AAH is diploid, as are most examples of low-grade adenocarcinoma. A few markers (blood group antigens, peanut agglutinin) show similar patterns of expression in AAH and adenocarcinoma while others (carbohydrate D-galactose-N-acetyl-D-galactosamine) do not. Recent cytogenetic analyses have detected abnormalities of chromosome 8 in a very small proportion (4-6%) of cases of AAH studied. CONCLUSIONS: Presently, the only strong evidence linking AAH to adenocarcinoma is morphologic. The few biologic and molecular/cytogenetic studies performed have not provided convincing evidence to support or refute this possibility. Additional studies are required. Finally, in comparative studies of AAH with adenocarcinoma, the latter should include low-grade transition zone tumors.

Adenocarcinoma↗
PubMed1996

Effects of long-term cocaine exposure on spermatogenesis and fertility in peripubertal male rats.

PURPOSE: This study was conducted to investigate the effects of long-term administration of cocaine on spermatogenesis and fertility in adult male rats. MATERIALS AND METHODS: Thirty-day-old male Sprague-Dawley rats were given cocaine hydrochloride (15 mg./kg. body weight, corresponding to an average single dose for a heavy cocaine user) either daily or twice weekly (weekend group, cocaine given on Saturday and Sunday) and mated with pregnancy-proven female rats after 100 and 150 days of exposure to the drug. Pregnancy rates and litter birth weights were evaluated. Serum testosterone, follicle stimulating hormone and luteinizing hormone levels were measured in all adult rats. Morphologic analysis of the testis entailed the evaluation of quantitative and qualitative histologic parameters to assess the effect of cocaine on various stages of spermatogenesis. RESULTS: After 100 days of treatment, the rats receiving daily cocaine had a pregnancy rate of only 33% versus 86% for the controls (p < 0.05). In rats exposed to cocaine for 150 days the pregnancy rate was 50% compared with 100% for controls (p < 0.05). The birth weights of offspring from the group receiving daily cocaine was 10% less than that of controls (p < 0.05). The weight of the testis and epididymis was not affected by cocaine exposure. Morphometric analysis showed significant differences between the cocaine-treated groups (both the daily cocaine and twice weekly cocaine groups) and their respective controls. The mean diameter of seminiferous tubules in the daily and twice weekly cocaine groups was reduced when compared with their respective controls. These differences between treated groups and their controls were statistically significant (p < 0.05). Similarly the thickness of the germinal epithelium was less in the cocaine-treated groups than in the controls (p < 0.05). Degenerating cells were more numerous in both daily and twice weekly cocaine groups than the controls. Furthermore, the number of step VII spermatids was reduced in both daily and twice weekly cocaine groups, a difference that was statistically significant (p < 0.05). CONCLUSION: Our findings demonstrate that chronic administration of cocaine to peripubertal male rats has a profound effect on their testicular function. Even with twice weekly administration there was a significant adverse effect on spermatogenesis although this was not manifested by diminished fertility in this group. These findings confirm that chronic administration of cocaine to male rats can have a deleterious effect on spermatogenesis and fertility.

Animals↗
PubMed1996

[Prognosis prediction in patients with transitional cell carcinoma of the urinary bladder].

OBJECTIVES: Many attempts have been made during decades to identify factors predictive of prognosis in patients with transitional cell carcinoma (TCC) of the bladder. The present study attempts to determine the predictive factors in a large series of patients with long follow-up homogeneously treated at three institutions from 1983 to 1992. METHODS: The clinical and histological factors with presumed prognostic value were retrospectively evaluated in a series of 331 patients with a mean follow-up of 7.2 years, and a study of survival was performed. RESULTS: Univariate analysis showed tumor stage, growth pattern, grade, size, coexisting dysplasia, histologic type, topography of the lesion and patient age are useful parameters for the prediction of prognosis. The Cox analysis revealed tumor stage is the most important prognostic variable (Beta = 1.23, p < .001), followed by growth pattern as determined by the presence or absence of a papillary phenotype (Beta = 1.18, p < .001), tumor size (Beta = .98, p < .001), WHO modified histologic grading considering persistence or loss of cell polarity (Beta = .73, p < .01), tumor location (Beta = .48, p < .05), and histology (presence or absence of phenotypes other than pure TCC, Beta = .45, p < .05). Coexisting dysplasia, tumor multiplicity, age and sex did not independently influence survival. CONCLUSION: Despite the advancements in the field of molecular biology relative to prognostic markers in bladder cancer, the conventional morphological parameters and tumor stage continue to be the main source of prognostic information in clinical practice.

Adult↗
PubMed1995

Evidence for three tumor suppressor gene loci on chromosome 8p in human prostate cancer.

Allelic loss of human chromosome sequences is often equated with inactivation of putative tumor suppressor genes. Loss of sequences on the short arm of chromosome 8 (8p) has been observed in human cancers, especially of 8p22 in prostate tumors. By using PCR analysis of highly polymorphic microsatellite repeat markers at nine 8p loci in 135 tumors, we observed deletion of sequences at 8p22 and at two other proximal deletion domains. These novel deletion domains encompass the NEFL locus and D8S87-ANK1 loci, respectively. These data suggest that three 8p tumor suppressor gene loci may be independently deleted in human prostate cancers.

Adult↗
PubMed1995

Localization of potential tumor suppressor loci to a < 2 Mb region on chromosome 17q in human prostate cancer.

We recently demonstrated a high frequency of loss of heterozygosity (LOH) at the D17S856 and D17S855 (within the BRCA1 gene) loci in primary prostate cancer, suggesting that the BRCA1 gene and/or other tumor suppressor gene(s) located within the interval of the D17S856 and D17S855 loci and/or within the vicinity of this interval may be important in prostate cancer (Cancer Res., 55: 1002-1005, 1995). To further define the exact boundary of the deleted region (i.e., D17S856/D17S855) and to detect other possible LOH regions on the long arm of chromosome 17, we analysed 23 matched normal and tumor DNAs with 15 polymorphic microsatellite markers spanning chromosome 17q12-21. Eleven of 22 (50%) informative tumors showed allelic deletion at one or more of the loci studied. A minimal area of LOH was identified to extend from the proximal boundary at the D17S776 locus to the distal boundary at the D17S855 locus, spanning an estimated < 2 Mb segment on chromosome 17q21. Our results suggest that a potential tumor suppressor gene(s) may reside in the < 2 Mb region centromeric (inclusive) to the BRCA1 gene and that this tumor suppressor gene(s) may be involved in the formation of prostate cancer.

Aged↗
PubMed1995

Somatic mutations of the WAF1/CIP1 gene in primary prostate cancer.

The WAF1/CIP1 gene, a potential tumor suppressor gene, has recently been cloned and identified as a p53 mediator and an inhibitor for G1 cyclin-dependent kinases (CDKs). We undertook this study to investigate the possible role of the WAF1/CIP1 gene in human prostatic carcinoma. Matched normal and cancer tissues from 18 patients with prostate cancer were screened for WAF1/CIP1 mutation by nested reverse transcription-polymerase chain reaction/single strand conformational polymorphism (RT-PCR/SSCP) and DNA sequencing. Shifted bands from three tumor, but not the matched normal specimens, were observed. Subsequent direct DNA sequencing of the PCR fragments identified four sequence alterations including a cytosine (C) to adenine (A) transversion and a guanine (G) to A transition and two A insertions. Our results demonstrated that mutations of the WAF1/CIP1 gene occur and may be important during the pathogenesis of human prostate cancer. This is the first report of WAF1/CIP1 mutation in a primary human cancer.

Base Sequence↗
PubMed1995

Loss of heterozygosity of the BRCA1 and other loci on chromosome 17q in human prostate cancer.

A putative tumor suppressor gene, the BRCA1 gene, on chromosome 17q21 has recently been identified and shown to be mutated in breast and ovarian cancers. We have undertaken the present study to explore the possible involvement of the BRCA1 and/or other potential genes on chromosome 17q in prostate cancer. Twenty-three patients were screened by PCR for loss of heterozygosity at five microsatellite loci spanning the region of 17q12-21. One of the loci (i.e., D17S855) studied is intragenic to the BRCA1. Forty-four and 40% of the informative cases showed loss of heterozygosity at the BRCA1 (D17S855) and D17S856 loci, respectively, whereas 10%, 10%, and 11% of the informative cases were positive for loss of heterozygosity at the D17S250, D17S579, and D17S588 loci, respectively. Overall, 52% (11/21) of the informative cases have allelic loss of at least one locus on chromosome 17q. Our data suggest that the BRCA1 and/or other genes within the interval between BRCA1 and D17S856 on 17q21 may be important in the pathogenesis of prostate cancer.

Adenocarcinoma↗
PubMed1995

Muscularis mucosa differentiates two populations with different prognosis in stage T1 bladder cancer.

OBJECTIVES: Contrary to previous belief, the existence of a muscularis mucosa in the human urinary bladder has now been well described. Although the degree of development of this structure seems variable, it can frequently be used to differentiate two levels within the subepithelial connective tissue: the lamina propria and the submucosa. The present study evaluates whether this morphologic feature is potentially useful for the identification of two populations with Stage T1 bladder cancer: those with tumor invasion confined to the lamina propria (pT1A) and those with tumors infiltrating into the submucosa (pT1B). METHODS: A series of 170 Stage T1 papillary bladder tumors was analyzed pathologically to identify the level of subepithelial connective tissue invasion. Both the reproducibility of such a differentiation and its prognostic implication were evaluated using Kaplan-Meier survival estimates and the Cox regression model. RESULTS: In specimens from transurethral resection, categorization into T1A or T1B could be performed in 98 of 170 cases (58% of specimens). Such differentiation proved to be of prognostic value with significantly different 5-year survivals between the two subcategories (pT1A [n = 50] vs pT1B [n = 49]) (log-rank, P < 0.02). Cox's regression analysis of pT1 subcategory and grade was performed in the 99 cases in which the differentiation between pT1A/pT1B could be made. This demonstrated that the depth of subepithelial connective tissue invasion was an independent prognostic factor (P < 0.05). CONCLUSIONS: The depth of tumor infiltration can be assessed in a considerable proportion of Stage T1 bladder neoplasms. The present study validates the prognostic significance of such a distinction both by Mantel-Haenszel life table method and Cox's regression analysis.

Actuarial Analysis↗
PubMed1995

Elevated 12-lipoxygenase mRNA expression correlates with advanced stage and poor differentiation of human prostate cancer.

OBJECTIVES: Prostate cancer is the most frequently diagnosed cancer and the second leading cause of cancer death in males in the United States. The mortality is due mainly to distant metastasis. Therefore, predicting the prognosis of prostate cancer patients is an important clinical problem. Previously, we demonstrated that a 12-lipoxygenase (12-LOX) metabolite of arachidonic acid, 12(S)-hydroxyeicosatetraenoic acid, enhances the invasiveness of prostate cancer cells and that a 12-LOX-selective inhibitor [N-benzyl-N-hydroxy-5-phenylpentanamide] reduces experimental metastasis in animal model systems. In this study, we investigated the potential of 12-LOX as a predictor for the aggressiveness of prostate cancer. METHODS: The mRNA expression level of 12-LOX in 122 matching prostate normal and cancerous tissues were measured by quantitative reverse transcription- polymerase chain reaction. Possible association between 12-LOX expression and histologic grade, pathologic and clinical stage, margin positivity, age, and race was analyzed. RESULTS: 12-LOX mRNA levels were elevated in cancer cells and the expression associated with poor differentiation and invasiveness of prostate cancer. Overall, 46 (38%) of 122 evaluable patients showed elevated levels of 12-LOX mRNA in prostate cancer tissues compared with the matching normal tissues. A statistically significantly greater number of cases were found to have an elevated level of 12-LOX among T3, high grade, and surgical margin-positive than T2, intermediate, and low grade, and surgical margin-negative prostatic adenocarcinomas. CONCLUSIONS: Our data suggest that elevation of 12-LOX mRNA expression occurs more frequently in advanced stage, high-grade prostate cancer and that 12-LOX may serve as an indicator for progression and prognosis of prostate cancer. This enzyme also may be a novel target for the development of anti-invasive and antimetastatic agents.

Adenocarcinoma↗
PubMed1995

Epidemiology of high grade prostatic intraepithelial neoplasia.

The prevalence of high grade prostatic intraepithelial neoplasia (HGPIN), the age at which this lesion starts and the potential racial or ethnic differences in its distribution are poorly documented. HGPIN is becoming increasingly implicated as a premalignant lesion for clinically significant prostatic carcinoma (PCa) with mounting evidence linking it to carcinoma according to morphologic immunohistochemical and recent genomic studies. We describe our experience with the age and race distribution of HGPIN resulting from two study populations of African-American (AA) and Caucasian (C) males. The first component of this report describes an autopsy study aimed at determining the prevalence of latent PCa and HGPIN in AA and C men 20 years of age or older; 370 (218 AA and 152 C) consecutive step-sectioned, totally embedded prostate glands were microscopically evaluated and mapped for HGPIN and PCa. HGPIN was first identified in the third decade and increased steadily with age. Latent PCa increased steadily with age with no significant difference in the prevalence between AA and C males in any age group (3rd to 8th decades). HGPIN, on the other hand, was more prevalent in AA men with 18, 31, 69, 78 and 86% in their 4th, 5th, 6th, 7th and 8th decades harboring the lesion. The corresponding figures for C men were 14, 21, 38, 50 and 63% respectively. When HGPIN was quantitated as focal and extensive according to the degree of glandular involvement, extensive HGPIN appeared earlier in AA males under 60 years of age compared to C males cohort. The difference in age distribution appeared to follow a chronological pattern, with HGPIN in AA preceding that of C males by approximately a decade. The second component of this report describes a surgical series of 345 consecutive radical prostatectomies from patients (155 AA and 190 C) with clinically localized PCa, which were thoroughly evaluated microscopically by two urologic pathologists. Similar to the findings in the autopsy study, extensive HGPIN was more prevalent in AA men 60 years of age or younger (57% vs. 33%). In both races, the mean percentage of the gland involved by HGPIN decreased with advancing age in contrast to the mean tumor volume that increased with patient age. These findings indicating a different prevalence of HGPIN in the two racial groups may help explain the higher incidence of prostatic cancer in African-Americans.

Adenocarcinoma↗
PubMed1995

Interobserver reproducibility in the diagnosis of prostatic intraepithelial neoplasia.

To assess interobserver reproducibility in the categorization of prostatic intraepithelial neoplasia (PIN) seven pathologists reviewed 25 lesions. Rather than classic or consecutive examples of PIN, cases were selected to represent the full spectrum of diagnostic issues in this field. Lesions were classified into one of six categories: (a) benign prostate tissue, (b) PIN1, (c) PIN2, (d) PIN3, (e) PIN3 cannot rule out associated cancer, and (f) PIN3 plus cancer. Following evaluation of the slides, data were also analyzed by combining several of the groups into three categories: (a) benign/PIN1; (b) PIN2/PIN3/PIN cannot rule out cancer; and (c) PIN plus cancer. The level of agreement was fair (Kappa = 0.33) for the six categories and substantial (Kappa = 0.61) for the three groups. In no case was there a uniform diagnosis of PIN1; in all cases at least some pathologists considered the biopsies to be normal. This finding provides support for not commenting on PIN1 in biopsy material. In general, there was good distinction between low-grade PIN (PIN1) and high-grade PIN (PIN2-3). Among the seven cases for which there was a consensus that the lesion represented high-grade PIN, there was no case in which there was uniform agreement as to whether the lesion represented PIN2 or PIN3. This finding supports combining PIN2 and PIN3 into high-grade PIN. Cases classified as low-grade PIN by some and as high-grade PIN by others were those with pleomorphism but without prominent nucleoli. Difficulties in distinguishing "high-grade PIN" from "high grade PIN cannot rule out cancer" were those with cribriform glands, glands with necrosis, and where high-grade PIN was associated with only a few adjacent small atypical glands. These same histologies caused the participating pathologists difficulty in distinguishing "high-grade PIN cannot rule cancer" from "high grade PIN plus cancer."

Biopsy, Needle↗
PubMed1995

Investigation of the tissue effects of a new device for intracorporeal lithotripsy--the Swiss Lithoclast.

Currently three modalities are available for intracorporeal stone fragmentation--electrohydraulic, ultrasound and laser lithotripsy. A new device, the Swiss Lithoclast, has been developed by the Departments of Medical Electronics and Urology at the University of Lausanne, Switzerland. This device has been used clinically in several countries for the treatment of stones throughout the human urinary tract. While no adverse outcomes have been reported, the potential tissue effects of the device have not been thoroughly investigated in an animal model. The objective of the present study is to evaluate the possible acute and long-term tissue effects of this instrument on the pig urinary tract. In all acute animals, visible mucosal lesions were seen at the site of probe firing in the bladders and ureters. Histologic examination demonstrated the effects of acute trauma with edema, hemorrhage and mucosal denudation. No significant long-term tissue effects were noted either pathologically or on radiographs in the 3- and 6-week animals. This study confirms our clinical impression that the Swiss Lithoclast effectively fragments urinary calculi and is associated with a large margin of safety.

Animals↗