Comparison of PathVysion and INFORM fluorescence in situ hybridization kits for assessment of HER-2/neu status in breast carcinoma.

BACKGROUND: Fluorescence in situ hybridization is advocated for precise assessment of HER-2/neu status in breast carcinoma; however, few objective data compare available kits for clinical laboratories contemplating development of the test. METHODS AND RESULTS: Thirty breast carcinomas were analyzed for HER-2/neu amplification with the PathVysion kit (Vysis, Downers Grove, IL) and INFORM kit (Ventana Medical Systems, Tucson, AZ). Each kit was evaluated for morphology, background staining, technical and interpretation time, and cost. PathVysion detected amplification in seven of 30 cases (23.3%); INFORM detected six of 30 cases (20%). A greater percentage of PathVysion cases showed good morphology and lower background staining than INFORM. Technical and interpretation times, as well as cost, were less with PathVysion than INFORM. CONCLUSION: PathVysion is superior to INFORM because it produces better morphology and less background staining and is faster and less expensive than the INFORM kit. It also includes a chromosome 17 probe that serves as an internal control and enables correction for chromosome 17 aneuploidy.

HER-2/neu assessment in breast cancer by immunohistochemistry and fluorescence in situ hybridization: comparison of results and correlation with survival.

BACKGROUND: HER-2/neu immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) results guide breast cancer therapy; however, few studies compared the results and no published studies have correlated them with patient outcome. METHODS AND RESULTS: We compared results, cost, and turnaround time in 117 archival, invasive breast carcinomas and compared 50-month survival in 65 of these cases using commercial HER-2/neu IHC and FISH assays. Twenty-one of 112 FISH (19%) and 33 of 117 IHC cases (28%) were positive. Concordance was high overall (88%; 98 of 112 cases) and in IHC 3+ cases (88%; 14 of 16 cases) but low in IHC 2+ cases (35%; six of 17 cases). Survival correlated with IHC results in 3+ cases (P =.02) and FISH cases with signal ratio greater than 4.0 (P =.03), but not in IHC 2+ cases (P=.7). Cost and turnaround time were greater for FISH. CONCLUSION: IHC is appropriate for initial HER-2/neu assessment; however, patients with tumors scored less than 3+, particularly those interpreted as 2+, would benefit from FISH to more accurately assess HER-2/neu status and avoid inaccurate prognostication and inappropriate treatment.

Comparison of jejunal and ileal surveillance biopsies in a porcine model of intestinal transplantation.

BACKGROUND: The optimal biopsy site of bowel allografts for rejection surveillance remains controversial. We compared the results of jejunal (JBx) and ileal (IBx) biopsies after bowel transplantation in a porcine model. METHODS: Eighteen Yorkshire-Landrace pigs served as donors. Eighteen recipient pigs underwent total enterectomy followed by orthotopic small bowel transplantation with or without the colon. A jejunostomy and a Bishop-Koop ileostomy were constructed for biopsies. Immunosuppression consisted of FK506 (target level 10-15 ng/ml by enzyme immunoparticle assay) and prednisone administered via the jejunostomy. Simultaneous JBx and IBx were performed twice weekly. Acute rejection was graded as mild, moderate, or severe based on previously published criteria. RESULTS: Mean overall survival after the transplant was 17.4 days. A total of 162 specimens were collected and evaluated for rejection (JBx, 81; IBx, 81). Acute rejection was detected in 41 JBx cases (50.7%) and 40 IBx cases (49.4%). The presence or absence of rejection was concordant between JBx and IBx in 70 of 81 case pairs (86.4%). Of the 11 discordant case pairs, 6 were JBx positive/IBx negative, whereas 5 were JBx negative/IBx positive. A total of 35 case pairs were synchronously positive, 24 (68.8%) of which demonstrated the same degree of rejection. CONCLUSIONS: The correlation between JBx and IBx of bowel allografts in diagnosing the presence of acute rejection is quite good. However, performing IBx alone would have missed about 7.5% of the rejection episodes. Because the early treatment of rejection in bowel transplantation is of paramount importance, in selected cases, biopsies from both the ileum and jejunum should be considered if technically feasible.

Thrombocytopenia in an established solitary pancreas graft recipient.

Isolated, life-threatening thrombocytopenia from a previously well tolerated pancreas allograft has not been reported in the literature. Herein we report such a case where a 31-year-old, Caucasian, Type I diabetic male developed severe thrombocytopenia 6 months following isolated pancreas transplantation and 2 wk after enteric conversion of the graft. Despite extensive diagnostic work-up, the cause remained unclear and his thrombocytopenia did not remit with standard treatment, but did resolve upon explantation. Pathologic examination of the pancreatic graft showed evidence of chronic rejection along with CMV pancreatitis. We conclude that unremitting isolated thrombocytopenia in solitary pancreas grafts may reflect a localized DIC phenomenon that requires graft explantation.

Incidence of post-transplant malignancy among 674 solid-organ-transplant recipients at a single center.

We evaluated the post-transplant course of the entire solid-organ-transplant population at our institution to determine the frequency, incidence and specific type of post-transplant malignancies which occurred at a single center. Of 674 solid-organ-transplant recipients (305 renal, 307 heart, 54 lung, 8 heart/lung), we detected 79 malignancies (48 heart, 28 renal, 2 lung, 1 heart/lung), representing an overall cancer frequency of 11.7%, 15.6% for heart and 9.2% for renal transplant recipients. The frequency in both transplant groups was higher than that reported previously in the multicenter data in the literature (about 6%); we also noted a shorter interval to malignancy (27 vs. 61 months). The most common malignancies overall were skin/lip carcinomas and post-transplant lymphoproliferative disorder (PTLD). The frequency of PTLD was higher in non-renal (6.5%) than renal (0.7%) transplant recipients and statistical analysis confirmed a significant higher incidence of all malignancies (p = 0.0032) and of PTLD (p = 0.0001) in heart and lung recipients as opposed to renal transplant recipients. The frequency of total skin/lip carcinomas was essentially equal in the heart and renal transplant groups (6%), and statistical analysis showed no significant difference in incidence of this general type of malignancy; however, there was a marked disparity in interval to squamous cell carcinoma (SCC) between renal and heart transplant recipients (27 versus 59 months). This was associated with an apparent increase in the rate of occurence of SCC after 60 months in heart transplant recipients, a finding not previously reported in the multicenter data in the literature. We did not demonstrate a significant effect of the withdrawal of prophylactic OKT3 from the immunosuppression regimen of heart transplant recipients on the incidence of all tumors, PTLD or skin/lip tumors.

Detection of clonal immunoglobulin heavy-chain gene rearrangements in cases of suspected lymphoproliferative disorders: comparison of polymerase chain reaction and Southern blot analysis.

Demonstration of clonality is supportive of a diagnosis of malignancy in cases of lymphoproliferative disorders. Determination of clonality at the molecular level is currently accomplished by Southern analysis; however, the polymerase chain reaction offers a potential alternative that is rapid, simple, and less expensive. To test its feasibility as a diagnostic test, we amplified the DNA from 121 suspected lymphoproliferative disorders submitted for gene rearrangement studies. In comparison to Southern analyses, a sensitivity of 70% and specificity of 96% were obtained. To test the effect of primer variability in the joining region of the heavy-chain gene, we substituted a more degenerate primer but found no changes in sensitivity or specificity. We conclude that the polymerase chain reaction has current application with minute or fixed specimens and may generally serve as a rapid, initial evaluation for B-cell clonality, followed by Southern analysis in negative cases. However, higher overall sensitivity must be achieved before this technique can replace Southern analysis as the method of choice in determining clonal gene rearrangements.

Giant forms of Blastomyces dermatitidis in the pulmonary lesions of blastomycosis. Potential confusion with Coccidioides immitis.

Typical yeast-phase cells of Blastomyces dermatitidis have a characteristic appearance in tissue sections. Fungal morphologic variation occurs infrequently in the lesions of blastomycosis, yet it can complicate the differential diagnosis, particularly if fresh tissue is not available for microbiologic culture. The authors report a case of pulmonary blastomycosis, confirmed by culture and direct immunofluorescence, in which some of the yeast-like cells were abnormally large. These giant yeast-like cells exceeded the size range accepted for the tissue forms of B. dermatitidis; therefore, coccidioidomycosis was considered initially in the differential diagnosis. Otherwise characteristic morphologic features of these cells, in particular multinucleation and the production of broad-based blastoconidia, helped resolve the differential diagnosis. The diagnosis can be confirmed by direct immunofluorescence or microbiologic culture.

Primary cardiac lymphoma initially diagnosed by routine cytology. Case report and literature review.

A case of primary cardiac lymphoma initially diagnosed by routine cytologic examination of pericardial fluid is presented. In a 64-year-old woman woman who originally presented with chest pain and heart block, the initial clinical impression was ischemic heart disease. However, coronary angiography failed to reveal significant disease. An echocardiogram demonstrated pericardial fluid, which was drained. A small amount was sent for cytologic examination, and the diagnosis of malignant lymphoma, large cell type, was made. Subsequent radiologic examinations revealed an intracardiac mass involving the atrioventricular canal; surgical biopsy confirmed the diagnosis of a large cell lymphoma. While primary malignant lymphoma of the heart is rare, this case highlights the efficacy of routine cytologic examination of an effusion fluid (often drained therapeutically) in establishing the correct diagnosis.