May 2004

ANATOMIC PATHOLOGY

Keratins 8, 10, 13, and 17 are useful markers in the diagnosis of human cervix carcinomas

Carla Carrilho, Matos Alberto, Landim Buane and Leonor David

Several candidate tumor markers for cervical neoplasia have been identified. Among those are keratin markers, whose precise implications in the diagnosis are still under debate. In the present study, authors aimed to clarify the usefulness of studying the expression of keratins 8, 10, 13, and 17 for diagnostic purposes in human cervix carcinomas. Forty-four invasive squamous carcinomas, 10 cervical intraepithelial neoplasia grade III (CIN III), and 10 reference cervix were examined immunohistochemically with monoclonal antibodies. Expression of keratins in reference exocervix, CIN III, and invasive carcinomas was as follows: keratin 80, 44.4%, and 57.1%, respectively; keratin 1077.8%, 40%, and 19%, respectively; keratin 13100%, 22.2%, and 25%, respectively; keratin 170, 40%, and 73.2%, respectively. In invasive carcinomas, expression of keratin 10 was significantly associated with keratinizing carcinomas. In conclusion, authors observed that expression of keratins 8 and 17 and loss of keratins 10 and 13 are good markers of malignant transformation in human cervix. Keratin expression patterns, namely expression of keratin 10, can be useful for subtyping and grading squamous cell carcinomas of the cervix.

Human Pathology, Volume 35, Issue 5, May 2004, Pages 546-551

Using tissue adjacent to carcinoma as a normal control: an obvious but questionable practice

Braakhuis BJ, Leemans CR, Brakenhoff RH.

When carcinoma tissue is investigated using biochemical, immunohistochemical, and genetic techniques, adjacent tissue that is macroscopically normal is frequently used as a control, since cancer-related pheno- and geno-typic alterations are assumed to be absent. However, a field that contains genetically abnormal cells surrounds a significant proportion of carcinomas (for example, over 30% of head and neck cancers). These fields can be large (>7 cm in diameter) and consist of cells that are clonally related to the carcinoma. This indicates that adjacent epithelium must be checked for genetic abnormalities before it is considered normal and used as a control for comparison with carcinoma.

J Pathol. 2004 Jun, 203(2): 620-621

Tissue distribution of ACE2 protein, the functional receptor for SARS coronavirus. A first step in understanding SARS pathogenesis.

Hamming I, Timens W, Bulthuis M, Lely A, Navis G, Van Goor H.

Severe acute respiratory syndrome (SARS) is an acute infectious disease that spreads mainly via the respiratory route. A distinct coronavirus (SARS-CoV) has been identified as the aetiological agent of SARS. Recently, a metallopeptidase named angiotensin-converting enzyme 2 (ACE2) has been identified as the functional receptor for SARS-CoV. Although ACE2 mRNA is known to be present in virtually all organs, its protein expression is largely unknown. Since identifying the possible route of infection has major implications for understanding the pathogenesis and future treatment strategies for SARS, the present study investigated the localization of ACE2 protein in various human organs (oral and nasal mucosa, nasopharynx, lung, stomach, small intestine, colon, skin, lymph nodes, thymus, bone marrow, spleen, liver, kidney, and brain). The most remarkable finding was the surface expression of ACE2 protein on lung alveolar epithelial cells and enterocytes of the small intestine. Furthermore, ACE2 was present in arterial and venous endothelial cells and arterial smooth muscle cells in all organs studied. In conclusion, ACE2 is abundantly present in humans in the epithelia of the lung and small intestine, which might provide possible routes of entry for the SARS-CoV. This epithelial expression, together with the presence of ACE2 in vascular endothelium, also provides a first step in understanding the pathogenesis of the main SARS disease manifestations.

J Pathol. 2004 Jun 203(2): 631-637

Histologic correlates of viral and bacterial infection of the placenta associated with severe morbidity and mortality in the newborn

Anjali Satosar, Nilsa C. Ramirez, Deborah Bartholomew, Jonathan Davis and Gerard J. Nuovo

The purpose of this study was to correlate the histologic features of the placenta with the in situ detection of viral or bacterial nucleic acids in cases of severe morbidity and mortality in the neonatal period. The criteria for the cases were either fetal or neonatal death cases with autopsy material available in 8 cases) or idiopathic severe respiratory distress or central nervous system-related symptoms at birth (49 cases). Controls included 11 placentas from births with no morbidity and 6 placentas that were associated with severe neonatal morbidity of known etiology (trisomy, ruptured uterus, prolapsed cord). The 77 placental tissues were analyzed with a consensus bacterial probe and for a wide variety of viral infections. An infectious cause was found in 46/60 (76%) of cases; these were distributed as follows: enterovirus, 23 cases (22 were coxsackie virus); bacterial (consensus probe), 15 cases; cytomegalovirus (CMV), 4 cases; herpes simplex virus (HSV), 2 cases; parvovirus, 2 cases. The infectious agents localized primarily to Hofbauer cells and trophoblasts. In each of the 8 cases for which autopsy material was available, the same infectious agent that was detected in the placenta was also detected in the autopsy material (spleen, heart, central nervous system, or lungs). No infectious agent was detected in any of the 17 controls. Viral inclusions (only evident for DNA viruses) and stem vessel vasculitis were the 2 histologic findings that were associated with infectious disease in the placenta (P = 0.025). These data show that infection of the villi is highly associated with neonatal morbidity and mortality and that the histologic findings are, in most cases, nonspecific for infection.

Human Pathology, Volume 35, Issue 5, May 2004, Pages 536-545

Prognostic relevance of histological grade and its components in node-negative breast cancer patients.

Volpi A, Bacci F, Paradiso A, Saragoni L, Scarpi E, Ricci M, Aldi M, Bianchi S, Muretto P, Nuzzo F, Simone G, Mangia A, Schittulli F, Amadori D.

Available results highlight the lack of good level of evidence studies on the pure prognostic value of histological grade. In the present study, the prognostic relevance of histological grade and of its three components, tubule formation, nuclear pleomorphism and mitotic count, was analyzed in a series of 372 patients with node-negative breast cancer treated with locoregional therapy alone until early relapse. Histological grade was determined blindly by two observers and discordance between evaluations was resolved after joint review using a multihead microscope. No relation was observed between histological grade and any of its three components and disease-free survival. Conversely, a significant relation was observed between histological grade and distant metastasis-free survival (at 6 years, 94, 86 and 76% for grades 1, 2 and 3, respectively, P=0.013) as well as overall survival (98, 90 and 86%, P=0.001). A breakdown analysis as a function of the three components showed that neither tubule formation nor nuclear pleomorphism was associated with prognosis, and only mitotic count strongly influenced both distant metastasis-free survival (91, 82 and 74%, P=0.014) and overall survival (97, 87 and 85%, P=0.011). Histological grade suffers from a much higher subjectivity than any other microscopic evaluation of biomarkers as it is the sum of three different morphological features. Within the Italian Network for Quality Assessment of Tumor Biomarkers program authors observed that histological grade is an independent prognostic variable, but also that this role is ascribable only to the number of mitotic figures. In conclusion, due to the ever smaller size of diagnosed breast cancers, resulting in less cancer tissue for biofunctional and molecular analysis, mitotic count evaluated under strict quality control conditions seems to be an accurate and feasible prognostic variable.

Mod Pathol. 2004 May 21

Nuclear markers (star volume, mitotic index, AgNOR and Ki-67) of the primary tumor and its metastasis in non-small cell lung carcinomas.

Matheus RS, Bernardi Fdel C, Gallo CP, da Silva AP, Rodrigues OR, Capelozzi M, Lopes A, Fenezelian S, Saldiva PH, Capelozzi VL.

Although tumor growth is controlled by growth rate and cell cycle, it is also likely that the proliferative activity of tumor cells can influence the growth rate of the primary cancer and account for their aggressiveness. Variations in growth rate, cell cycle control and proliferative activity could, in part, explain differences in invasive and metastatic properties among non-small cell lung carcinomas (NSLC). The purpose of this report is to: (1) evaluate growth rate by using growth- and cell cycle-regulating markers (mitotic count, nuclear star volume, AgNOR, and Ki-67) as reflections of growth rate and (2) compare the indices of primary NSLC with the indices of their metastasis in a series of patients with advanced disease. Thirty-three patients with non-small cell lung cancer and hematogenous metastases were retrospectively studied by histochemical, immunohistochemical, and morphometrical investigations. Clinical variables were examined for differences in the frequency of histological subtypes, nuclear star volume, mitotic index, AgNOR area, and Ki-67 immunohistochemistry indices of expression in subgroups of patients stratified by primary tumor and hematogenic metastasis. The impact of these factors on overall follow-up was analyzed. In the samples available in this study, consisting of primary-met paired tumors, which are unique and rarely available for studies of lung cancer, we found that nuclear star volume and mitotic index in metastatic tumors were significantly higher than in the primary tumors. Although there was no significant difference between the Ki-67 index of metastatic and primary tumors, the Ki-67 index in metastatic brain tumors was significantly higher than in the corresponding primary tumors. Examination of Kaplan-Meier survival curves demonstrated that patients with metastatic tumors showing AgNOR area higher than 10.82 microm2 and nuclear star volume lower than 559.50 microm3 had approximately the same odds ratio (log rank of 4.16 and 3.25, p = 0.04 and 0.01, respectively) for survival with a median survival time equal to 17 months for both groups. Analysis of the remaining marker correlation had no impact on survival. Authors conclude that these results offer future possibilities for more complex studies, including the results of additional immunohistochemical analysis using molecular markers that are known to be important in regulating cell proliferation, e.g., cyclin D1, p27, and cyclin E. These would influence clinical decisions or different therapeutic approaches in advanced stage disease of non-small cell lung cancer.

Pathol Res Pract. 2004, 200(1): 13-23

MICROBIOLOGY

Viability of mycobacteria in formalin-fixed lungs.

Gerston KF, Blumberg L, Tshabalala VA, Murray J.

It is generally accepted that the risk of contracting tuberculosis is relatively high among medical laboratory workers and pathologists. Nevertheless, there is an assumption that once tissue is fixed in formalin, the risk for transmission and subsequent infection of mycobacteria is greatly reduced, if not altogether eliminated. To test the viability of potentially infectious mycobacteria in formalin-fixed tissue, tissue specimens from autopsy lungs fixed in formalin were cultured for mycobacteria. Of 138 cases with histologic evidence of acid-fast bacilli, 12 grew mycobacteria, including 3 Mycobacterium tuberculosis isolates, suggesting that there is a risk of contracting tuberculosis from tissue that has been fixed in formalin, if aerosolization or accidental inoculation should occur.

Hum Pathol. 2004 May, 35(5): 571-5

BOTTOM LINE

Ten things I wish Id known when I was 25

R Persaud

Postgraduate Medical Journal 2004; 80:171