Thomas D. Trainer

DNA replication regulation protein Mcm7 as a marker of proliferation in prostate cancer

Background: Recent studies have shown that minichromosome maintenance (MCM) proteins (Mcm2–7) may be useful proliferation markers in dysplasia and cancer in various tissues. Aims: To investigate the use of Mcm7 as a proliferation marker in 79 lymph node negative prostate cancers and compare it with Ki-67, a commonly used cell proliferation marker. Methods: The percentage of proliferating cells (proliferation index; PI) was calculated for basal and luminal epithelial cells in benign prostate tissue, prostatic intraepithelial neoplasia (PIN), and epithelial cells in adenocarcinoma. The PI for each biomarker was correlated with the preoperative prostate specific antigen concentration, the Gleason score, surgical resection margin status, and the AJCC pT stage for each patient. Results: The mean PIs for Ki-67 and Mcm7 were: benign luminal epithelium 0.7 and 1.2 and benign basal epithelium 0.8 and 8.2; PIN non-basal epithelium 4.9 and 10.6 and PIN basal epithelium 0.7 and 3.1; adenocarcinoma 9.8 and 22.7, respectively. Mcm7 had a significantly higher mean PI (p<0.0001) than Ki-67 for all cell categories except benign luminal epithelial cells. Mcm7 was a better discriminatory marker of proliferation between benign epithelium, PIN, and invasive adenocarcinoma (p<0.0001) than Ki-67. The drop in Mcm7 mean basal cell PI from benign epithelium to PIN epithelium was significantly larger than for Ki-67 (p<0.0001). Mcm7 had a significantly higher PI than Ki-67 at each risk level. Conclusion: Mcm7 may be a useful proliferation marker in prostatic neoplasia and warrants further evaluation as a complementary tool in the diagnosis of PIN and prostate carcinoma.

Histopathological Features of the Terminal Ileum in Lymphocytic and Collagenous Colitis: A Study of 32 Cases and Review of Literature

Biopsy specimens from the terminal ileum of 32 patients with the histopathological diagnosis of lymphocytic colitis or collagenous colitis and 11 control individuals were evaluated for the presence or absence of ileal mucosal abnormalities and for the number of intraepithelial lymphocytes, assessed by immunohistochemical stains for the pan T-cell marker, CD3. We found that the mean CD3 counts in patients with lymphocytic/collagenous colitis were significantly higher than those in the control group. Seven of 14 patients with collagenous colitis and 14 of 18 patients with lymphocytic colitis revealed an increase in intraepithelial T lymphocytes when compared with the control group (P = .001). Other notable changes included ileal villous atrophy in one case of lymphocytic colitis and in three cases of collagenous colitis and epithelial damage with thickened subepithelial collagen in two cases of collagenous colitis.

Variability of grade and stage in simultaneous paired liver biopsies in patients with hepatitis C

Background: Grading and staging of liver biopsies in patients with chronic hepatitis remains an inexact “gold standard” that is influenced by variabilities in scoring systems, sampling, observer agreement and expertise. Spatial disease variability relative to markers of the adequacy of biopsy has not been studied previously. Methods: Paired liver biopsy specimens were obtained from the right and left hepatic lobes of 60 patients with chronic hepatitis C. Histological grade and disease stage were assessed according to the Ludwig scoring system, and scores were evaluated in relation to differences in size and number of portal tracts in all paired samples. Results: The relative difference (%) in aggregate biopsy size and number of portal tracts was similar between paired samples with and without a difference in grade. Paired samples with a difference in stage showed a larger relative difference in biopsy size (p = 0.09) and in the number of portal tracts (p = 0.016). Conclusions: Our study shows a difference of one grade or one stage in 30% of paired liver biopsies, due to a combination of sampling variability and observer variability. Acknowledgment of “built-in” variability in grading and staging chronic hepatitis C by both clinicians and pathologists is essential for managing the individual patient with chronic hepatitis C.

A rapid method for the analysis of creatine phosphokinase isoenzymes

Abstract A simplified method for analysis of creatine phosphokinase isoenzymes on cellulose acetate is described. Three bands, corresponding to those seen on agar gel, are identified. Results with a commercially available incubation mixture were identical to those obtained with our own reagents and obviated many of the problems associated with maintaining and replenishing relatively expensive reagents.

Incipient germ cell tumor in a cryptorchid testis.

A 13‐year‐old male who had bilateral cryptorchid testes since birth underwent testicular biopsies and subsequent left orchiectomy following a diagnosis of malignant germ cell tumor. No tumor mass was noted although the malignant cells were seen within the seminiferous tubules and the interstitium. Five recorded cases of in‐situ or incipient germ cell neoplasms of the testes are reviewed; three were infertile, another had a cryptorchid testis, and the fifth was both infertile and cryptorchid. Two of these patients have developed frank carcinoma, which would suggest that the process represents an early phase of invasive germ cell neoplasia.

Detection of Sarcocystis Parasites in Retail Beef : A Regional Survey Combining Histological and Genetic Detection Methods

Sarcocystis spp. are parasitic protists acquired when undercooked, cyst-laden meat is consumed. While both Sarcocystis hominis and S. cruzi encyst in beef, only S. hominis is pathogenic to humans. In this study, we used histological methods and novel molecular techniques to determine the regional prevalence and identity of Sarcocystis spp. in retail beef. Of 110 samples, 60 supported amplification of parasite rRNA by PCR. All 41 sequenced representatives were identified as S. cruzi. To compare detection methods, 48 samples were then examined in parallel by histology and PCR, and 16 and 26 samples, respectively, were positive. Five samples positive by initial histologic sections were not amplified by PCR. Fifteen PCR-positive samples did not contain sarcocysts on initial histologic section, but additional sections from these samples revealed sarcocysts in an additional 12 samples. When combined, histology with additional sections and PCR detected 31 positive specimens of the 48 total specimens. We found no evidence of human pathogen S. hominis and confirm that cattle pathogen S. cruzi is highly prevalent in this regional sample. PCR assays may increase the detection sensitivity of Sarcocystis spp. and contribute diagnostic precision.

Collagenous gastritis: a long-term follow-up with the development of endocrine cell hyperplasia, intestinal metaplasia, and epithelial changes indeterminate for dysplasia.

This report reviews the literature pertaining to collagenous gastritis and describes the clinicopathologic evolution of this disease in a patient during a 12-year period. We examined 109 biopsy specimens of gastric mucosa from 19 different endoscopic procedures for the severity and distribution of collagenous gastritis in a single patient. Assessments were undertaken for the presence of endocrine and gastrin cell hyperplasias and dysplastic epithelial changes. Relative to biopsy specimens from age- and sex-matched control subjects, the patients biopsy specimens showed a significantly lower number of antral gastrin cells, along with a significant corpus endocrine cell hyperplasia, suggesting an increased risk of endocrine neoplasia. Gastric corpus biopsy specimens revealed an active, chronic gastritis, subepithelial collagen deposition, smooth muscle hyperplasia, and mild to moderate glandular atrophy. Additional findings of intestinal metaplasia and reactive epithelial changes indeterminate for dysplasia raise concerns about the potential for adenocarcinoma.

Development of the Human Fetal Testis

We describe the histological features of the fetal testis, utilizing 68 fetuses ranging in gestational age from 10 to 41 weeks. During fetal life, the tunica albuginea progressively increases in thickness, and between 29 and 32 weeks it develops two layers. Beyond 25 to 28 weeks, septa are invariably present. Tubules begin as straight structures and become maximally coiled by 30 weeks. Tubular diameter reaches its maximum by 16 weeks and remains constant throughout the rest of gestation. Germ cell and Sertoli cell numbers per tubular diameter have a wide range, but the median number for each cell type remains constant after 13 to 16 weeks. Leydig cells are most numerous between 17 and 19 weeks and decline thereafter. They are infrequent but still present at term. Interstitial lipochrome pigment accumulates during the latter half of gestation and may represent breakdown products from Leydig cell degeneration.

Ultrastructural Study of a Pituitary Adenoma (Prolactinoma) Within the Clivus Bone Using Immunoelectron Microscopy

In a case of a pituitary adenoma in the clivus bone in a 71-year-old man, ultrastructural investigation using conventional aldehyde-fixed, epoxy-embedded tissue revealed the tumor to be composed of cells with euchromatic nuclei, dense nucleoli, abundant rough endoplasmic reticulum, spherical secretory granules, and granule extrusion at the lateral cell surface, all of which suggest a prolactin-producing adenoma. Using a protein A-gold immunolabeling technique on snap-frozen tissue subsequently fixed in a mild fixative and embedded in a hydrophilic resin, the presence of prolactin immunoreactivity within secretory granules at the ultrastructural level was demonstrated. This case represented the first use of protein A-gold immunolabeling at the electron microscopic level for diagnostic purposes at our institution and exemplifies the value of this technique when the need for diagnostic immunoelectron microscopy is not anticipated. Because this tumor arose in an unusual location, ultrastructural study, including immunoelectron microscopy, not only confirmed the light microscopic diagnosis of pituitary adenoma, but further allowed subclassification of the tumor.

Systemic amyloidosis involving two renal transplants

Two patients with primary amyloidosis, each of whom had received a renal transplant for chronic renal failure, developed amyloid in their allografts. In one patient amyloid was present primarily in glomeruli and to a lesser extent in the interstitial tissue. This patient developed renal failure necessitating retransplantation. In the second patient amyloid was seen in the interstitium and interlobular blood vessels. Minimal amyloid was present in the glomeruli. This patient died of cardiac amyloidosis with good graft function at the time of death. Of the several patients recorded in the literature with amyloid in renal allografts, our first patient is the only one to exhibit glomerular amyloid and failure of the graft. Amyloid in areas other than the glomerulus does not appear to be incompatible with satisfactory graft function.