Ferritin Immunohistochemical Localization in Normal and Neoplastic Colonic Mucosa

High levels of ferritin have been detected in serum and tumoral extracts of gastrointestinal neoplasms. However, its histological localization is not well known. An immunoperoxidase technique (PAP) was used for detecting ferritin in 30 colorectal carcinomas, 20 polyps and 8 cases of non-neoplastic mucosae. Ferritin staining was detected in stromal cells (98%) much more than in epithelial cells (21%). Connective cells were positive in 5 cases of normal mucosae (62%), 19 polyps (95%) and all carcinomas (100%). The number of positive cells gradually rose from normal mucosa to carcinoma with an intermediate score in adenomas. However, no relation could be found between the stromal ferritin score and dysplasia in polyps. Likewise, no relation was found between the stromal ferritin score and the differentiation grade, invasion or metastases in carcinomas. The positive epithelial pattern seen in 12 cases (21%) suggests non-specific staining due to passive diffusion from the stroma. Thus, these immunohistochemical findings suggest that in colonic neoplasms, ferritin could be a tumor marker produced mainly by stromal cell reaction more than by the epithelial cells.

Role of ancillary techniques in profiling unclassified laryngeal malignancies

Laryngeal biopsies, contrary to biopsies from many other sites of the body, very often contain minute amounts of tumour tissue that may consist of morphologically undifferentiated tumour only. In haematoxylin- and eosin-stained sections, there may be no indicative features of what specific tumour entity that is present. In the larynx, particularly small round cell neoplasms, primary or metastatic, often cause a diagnostic dilemma and where an incorrect diagnosis can induce substantial clinical consequences for the patient (e.g., primary neuroendocrine carcinomas vs metastatic variants, certain sarcomas). If sufficient/representative material has been obtained, the application of immunohistochemistry and/or molecular techniques should in virtually every case reveal the true nature of the malignancy. In cases with sparse amount of material, and therefore a limited number of sections to be cut, a careful and thoughtful stepwise approach is necessary to ascertain a reliable diagnosis, or at least guide the clinician to the most likely diagnoses. With today's advanced and widely available technology with an abundance of markers to discriminate different tumours, the use of the term "undifferentiated" should be largely unnecessary. In the exceptional, and indeed exceedingly rare cases, when a classification is not possible, even after repeat biopsy, we suggest that the laryngeal neoplasm is better termed "unclassified malignant neoplasm" rather than "undifferentiated malignant neoplasm".

[Post operative Caldwell-Luc procedure maxillary cyst: Report of a case]

Rare complication of radical surgery (Caldwell Luc procedure) of the maxillary sinus, maxillary cyst can occurred several years after. We describe the case of a patient 56 years old, who came to our consultationfor repeated pain in the right maxillary region with moderate facial asymmetry. In her history we noted a previous sinus surgery (Caldwell Luc) more than 10 years before. The imaging showed an expansive process filled with proteinic tissue of the posterior wall of the maxillary. With the history of the former surgery, we suspected the existence of a mucocele. She underwent an endonasal surgery and the pathological examination of the specimen revealed an intra osseous cyst lined with ciliated respiratory type mucosa post surgery of the maxillary sinus. The diagnosis of a maxillary cyst complicating a Caldwell Luc was established based on the results obtained with the clinico-radiological and pathological results.

Desmosomes in verrucous carcinoma of the head and neck

Verrucous carcinoma (VC) is a variant of squamous cell carcinoma (SCC), characterised by its inability to metastasize. In contrast, hybrid carcinomas, composed of VC and foci of conventional SCC, harbour a metastatic potential. Correct pathohistological diagnosis is therefore crucial for the choice of treatment. There is mounting evidence that desmosomes are involved in several aspects of carcinogenesis. Previous studies have shown an altered expression of desmosomal components in conventional SCC, which was associated with tumour behaviour, but no data have been found on desmosomes in VC. We therefore analysed the expression of desmosomal components in biopsy samples of 21 cases of VC and 5 cases of hybrid carcinoma of the head and neck in comparison to 23 cases of conventional SCC and 47 samples of normal squamous epithelium of similar localisation, using immunohistochemistry and real-time reverse-transcription polymerase chain reaction. We found that the expression patterns of desmosomal components in VC were fairly similar to those in normal epithelium but differed significantly from those in conventional SCC. Immunohistochemical reactions against desmosomal components disclosed the foci of SCC in hybrid carcinomas. In conclusion, we believe that expression patterns of desmosomal components in VC are consistent with its less aggressive behaviour. Differential expression of desmosomal components between VC and SCC makes some desmosomal components potentially useful in the diagnostics of VC, especially for the detection of hybrid carcinoma.

Activation of the EGFR/ERK pathway in high-grade mucoepidermoid carcinomas of the salivary glands

Background:

Mucoepidermoid carcinoma (MEC) shows differences in biological behaviour depending mainly on its histological grade. High-grade tumours usually have an aggressive biological course and they require additional oncological treatment after surgery.

Methods:

In a series of 43 MECs of the salivary glands, we studied the epidermal growth factor receptor (EGFR) gene by using dual-colour chromogenic in situ hybridisation (CISH). Moreover, we assessed the protein expressions of the EGFR and the activated extracellular signal-regulated kinases (pERK1/2) by using immunohistochemistry. These results were correlated with the histological grade of the tumours and the outcome of the patients.

Results:

The CISH study demonstrated a high-EGFR gene copy number, with balanced chromosome 7 polysomy, in 8 out of 11 high-grade MECs (72.7%), whereas 27 low-grade and 15 intermediate-grade tumours had a normal EGFR gene copy number (P<0.001). The EGFR gene gains correlated with disease-free interval (P=0.003) and overall survival of the patients (P=0.019). The EGFR protein expression had a significant correlation with the histological grade of the tumours but not with the outcome of the patients. The pERK1/2 expression correlated with histological grade of tumours (P<0.001), disease-free interval (P=0.004) and overall survival (P=0.001).

Conclusions:

The EGFR/ERK pathway is activated in high-grade MECs with aggressive behaviour. Patients with these tumours who require oncological treatment in addition to surgery could benefit from EGFR and mitogen-activated protein kinase pathway inhibitors.

ATM gene expression is associated with differentiation and angiogenesis in infiltrating breast carcinomas

The product of the ATM gene, mutated in the human genetic disorder ataxia-telangiectasia (A-T) plays a key role in the detection and repair of DNA double-strand breaks. A-T is defined by progressive cerebellar ataxia, telangiectasia, sensitivity to ionising radiation and genomic instability with cancer predisposition. On the other hand, increased angiogenesis is essential for tumor growth and metastasis. The aim of this study was to investigate ATM expression in breast carcinomas and its relationship to neoangiogenesis.

METHODS AND RESULTS

Fifty-two breast tumors from 51 patients, 38 of them with concomitant in situ component (CIS), were analyzed by immunohistochemistry for the expression of ATM. CD34 expression was used for the morphometric evaluation of vasculature. ATM was positive in 1 to 10% of normal epithelial cells. ATM expression was reduced in 55.8% of infiltrating carcinomas, non-reduced in 34.6%, and increased in 9.6%. Expression of ATM in CIS was similar to the infiltrating component in 71% of cases and reduced in 23.7% of them. High-grade ductal infiltrating carcinomas showed lower ATM expression than low-grade ones. Reduced ATM expression also correlated with increased microvascular area.

CONCLUSIONS

Reduced ATM expression in breast carcinomas correlated with tumor differentiation and increased microvascular parameters, supporting its role in neoangiogenesis and tumor progression in breast carcinogenesis.

Serial Topoisomerase II Expression in Primary Breast Cancer and Response to Neoadjuvant Anthracycline-Based Chemotherapy

OBJECTIVE

We analyzed the value of topoisomerase IIalpha (Topo II) in predicting the clinical response to anthracycline-based neoadjuvant chemotherapy in breast cancers and the potential changes in Topo II after chemotherapy. In parallel, HER2, which is commonly coexpressed with Topo II, and p53, a modulator of chemotherapy activity, were also analyzed.

METHODS

Forty-one patients with primary breast cancer and treated with neoadjuvant anthracycline-based chemotherapy (FAC or FEC) were included for the present study. Topo II, HER2 and p53 expression were measured by immunohistochemistry in pre and post chemotherapy (at the time of surgery), tumor specimens and the results were correlated with the clinical response.

RESULTS

Topo II was overexpressed in 16 of 41 (31%) tumors before treatment, and this overexpression was significantly associated with clinical response (p = 0.03). HER2 and p53 were unrelated to response. Notably, Topo II overexpression, but not HER2 or p53, was lost in specimens after chemotherapy (p = 0.01).

CONCLUSION

The observed link between Topo II and the clinical response to neoadjuvant anthracycline-based chemotherapy, together with its loss after chemotherapy, implies that Topo II deserves further testing in a prospective setting as a predictive marker.

Adenosquamous carcinoma of the head and neck: criteria for diagnosis in a study of 12 cases

AIMS

Adenosquamous carcinoma (ASC) of the head and neck is an unusual neoplasm in which a general consensus with regard to diagnostic criteria has not yet been reached. In this study we report the clinicopathological results of 12 ASCs, with special attention to their histological and immunohistochemical characteristics in order to define this neoplasm more precisely.

METHODS AND RESULTS

All the patients were male with a peak incidence in the sixth decade of life. The tumours were located most frequently in the larynx and oral cavity, followed by the nasal cavity and pharynx. ASCs had two distinct histological components. The most extensive one was an usual keratinizing squamous cell carcinoma, arising from the surface epithelium, where characteristically severe dysplasia or carcinoma in situ was found in all cases. The second component was an adenocarcinoma, usually displayed in the deepest areas of the tumour. Evidence of origin from salivary or seromucinous glands was not found. Immunohistochemical studies demonstrated in most cases positivity of glandular differentiated areas for carcinoembryonic antigen (CEA) (11/12), CK7 (9/12) and CAM5.2 (7/12), whereas the squamous cell component was unreactive or reacted only focally for these markers. High-molecular-weight cytokeratin 34BE12 was positive in both components and CK20 was always negative. All cases showed high expression of Ki67 antigen. Most of them had overexpression of p53 (8/12) and DNA aneuploidy (10/12). Fifty percent of patients with ASC died of disease after a mean period of 23 months (range 12-35 months).

CONCLUSIONS

ASC of the head and neck is an aggressive neoplasm that originates in the surface epithelium of the upper respiratory tract. Severe dysplasia or carcinoma in situ is usually found and its recognition helps to make the diagnosis. In addition to mucin stains, positive immunoreactivity for CEA, CK7 and CAM5.2 helps to identify the glandular component.

Plexiform ameloblastoma presenting as a sinonasal tumor

Ameloblastomas are the most frequent odontogenic tumours, accounting for 1% of all tumours of the maxilla and mandible. Sinonasal ameloblastomas are most common between the ages of 55 and 65, and mandibular ameloblastomas between 40 and 50. Incidence is higher in males than in females, and there are no differences between races. These locally aggressive tumours originate in the mandible in 80% of cases and in the maxilla in 15-20%. We report an unusual primary nasosinusal ameloblastoma presented in a 68-year-old male. The tumour was completely resected by (para)lateral rhinotomy and treated with postoperative radiotherapy. Histological analysis demonstrated a plexiform ameloblastoma. The patient remains well without disease after 50 months of postoperative follow-up.

Sinonasal tubulopapillary low-grade adenocarcinoma. Histopathological, immunohistochemical and ultrastructural features of poorly recognised entity

We present the clinicopathological, histological and immunohistochemical findings of six cases of primary tubulopapillary low-grade adenocarcinoma of the sinonasal tract with ultrastructural examination in one case. Due to its unique features, we believe that primary tubulopapillary low-grade adenocarcinoma of the sinonasal tract represents a tumour entity different from any tumours generally recognised in the sinonasal region. Our cases had an equal sex incidence, with an age range of 44-76 years. The tumour has a tendency to recur, but none of our six patients developed metastases. We feel that it is important to separate this tumour entity from other types of sinonasal adenocarcinomas that exhibit a papillary growth pattern, as they frequently pursue a much more aggressive clinical course than the tumours in this study.

[Sino-nasal endoscopic surgery in fungal sinusitis. Our experience]

Fungal sinusitis is a rare entity which has increased amongst immunocompromised individuals. Records of thirteen patients treated of fungal sinus disease between 1995 and 2001 were reviewed. Histopathological studies demonstrated infection due to Aspergillus in eight patients and due to Mucormycosis in five patients. The surgical debridement via endoscopic sinus surgery was the essential part of the management. The follow-up is 12-72 months (mean 29.08). The main clinical findings and a review of the literature are presented. We conclude that endoscopic sinus surgery is the treatment of choice for fungal sinusitis except in advanced cases of mucormycosis in which a combined approach is still necessary together with intravenous antifungal drugs (amphotericin B).

Mesonephric adenocarcinoma of the uterine corpus: CD10 expression as evidence of mesonephric differentiation

Mesonephric (wolffian) neoplasms of the female genital tract are infrequent and found in sites where embryonic remnants of wolffian origin are usually detected, such as the uterine cervix, broad ligament, mesosalpinx, and ovary. Their diagnosis is difficult because of the absence of specific immunohistochemical markers for mesonephric derivatives. We present the first report of adenocarcinoma of mesonephric type arising as a purely myometrial mass without endometrial or cervical involvement in the uterine corpus of a 33-year-old woman. The tumor showed a combination of patterns, with retiform areas, ductal foci, and small tubules with eosinophilic secretion, which merged with solid sheets of cells with a sarcomatoid appearance. Immunohistochemically, neoplastic cells were diffusely positive for cytokeratin 7, epithelial membrane antigen, and CD15 and focally positive for BerEP4 and vimentin. A hitherto unreported feature was the positivity for CD10 in neoplastic cells, which was also present in a large number of control tissues obtained from male mesonephric derivatives and female mesonephric remnants and tumors. Furthermore, CD10 was negative in controls from müllerian epithelia of the female genital tract and in their corresponding tumors. Therefore, the expression of CD10 by mesonephric remnants may be useful in establishing the diagnosis of tumors with mesonephric differentiation.

Renal expression of intercellular adhesion molecule-1 in immunoglobulin A nephropathy: tubulointerstitial injury and prognosis

In immunoglobulin A nephropathy (IgAN), the abnormal expression of intercellular adhesion molecule-1 (ICAM-1) on proximal tubule epithelium is associated with the glomerular and interstitial infiltration of leucocytes, but its clinical significance remains uncertain. We analysed the relationship between the ICAM-1 (CD54) expression in tubular epithelial cells and interstitial leucocytes, macrophages (CD14) and T lymphocytes (CD3) with the histologic features, proteinuria and serum creatinine at the time of renal biopsy and after 2.42 years in 45 patients with IgAN and after 1.8+/-1.5 years in 29 patients with non-glomerulonephritis (non-GN). In IgAN, ICAM-1+ tubule epithelium was 0.1+/-0.18 (x+/-SD), and this was associated with extracapillary proliferation (up to 20% of Bowman's space), glomerular sclerosis involving less than 50% of glomerular area, interstitial cellular infiltration, tubular atrophy and proteinuria level. ICAM-1+ interstitial leucocytes were correlated with glomerular sclerosis involving less than 50% of glomerular area, glomerular sclerosis involving more than 50% of glomerular area, tubular atrophy, interstitial fibrosis and serum creatinine level. In patients with an increase of 50% in serum creatinine, ICAM-1+, CD14+ and CD3+, interstitial leucocytes were significantly outnumbered than in patients with stable serum creatinine. In non-GN, ICAM-1+ tubule epithelium was 0.02+/-0.04 (U=344, P<0.05, vs IgAN), and this was inversely correlated with the percentage of the normal glomeruli and associated with glomerular sclerosis covering more than 50% of glomerular area, tubular atrophy and serum creatinine level. The association between tubular ICAM-1 and proteinuria and the association between interstitial ICAM-1+, CD14+ and CD3+, leucocytes and renal failure at presentation and the deterioration in IgAN in contrast with non-GN suggest that tubular and interstitial expression of ICAM-1 may be a marker of tubulointerstitial disturbance in IgAN.

Tissue macroarrays ("microchops") for gene expression analysis

We describe a simple system of tissue arraying with multiple tissue fragments obtained with a biopsy punch from selected areas of paraffin blocks. The new blocks thus constructed allow multiple tissue sections in which the uniform shape of the fragments coupled with a geometrical display and a significant amount of tissue per case allows a dependable, cost-effective way to screen tumors or other kinds of tissues with techniques such as immunohistochemistry. This system avoids the disadvantages of previous laborious methods of tissue arraying, such as expensive equipment and scarce tissue sampling, and it can be implemented in any institution with minimal cost and elaboration.

Expression of cathepsins B and S in the progression of prostate carcinoma

Cathepsins B and S (CatB, CatS) are lysosomal cysteine proteases which, among other functions, appear to play a role in cancer progression in different tumor models due to their matrix-degrading properties. To investigate their possible involvement in the development of prostate carcinoma, we immunohistochemically analyzed CatB and CatS in 38 primary human prostatic adenocarcinomas, as well as concomitant high-grade prostatic intra-epithelial neoplasia, nodular hyperplasia and normal tissue. CatB expression was observed in 28 (74%) and CatS in 32 (84%) carcinomas, being concomitant in 24 cases (63%). High-grade intra-epithelial neoplasia expressed CatB in 20/23 cases (87%), and a similar result was obtained for CatS, with expression of both coinciding in 18 cases (78%). In non-neoplastic tissue, strong expression of both proteases was observed in macrophages, inflamed glands and transitional metaplasia, whereas atrophic glands and basal cells of normal glands displayed intense CatB positivity. We conclude that CatB and CatS are often expressed together in neoplastic prostatic cells from pre-invasive to invasive and clinically detectable stages, suggesting a putative role in local invasion, though other functions cannot be ruled out.

Differential expression of cdc25 cell-cycle-activating phosphatases in human colorectal carcinoma

cdc25 is a family of cell-cycle phosphatases that activate the cyclin-dependent kinases. cdc25A and B, but not C, have oncogenic potential in vitro. In this study, we analyzed the possible implication of cdc25 genes in the progression of colorectal tumors. RNA and DNA were extracted from 34 paired tumor and normal colorectal tissues and examined by Northern blot, RT-PCR, and Southern blot, respectively. Protein expression was analyzed by Western blot in a subset of normal and tumor samples. The expression levels were correlated with the clinicopathologic characteristics and survival of the patients. cdc25B mRNA was overexpressed in 19 carcinomas (56%). A significant correlation was observed between high cdc25B mRNA levels and the relapse-free, overall, and cancer-related survival of the patients. The cdc25B2 splicing variant was detected in 27 carcinomas (79%) but only in 9 normal samples (26%) and was associated with the grade of the differentiation of the tumors. cdc25A mRNA was overexpressed in four tumors (12%) and cdc25C1 mRNA was overexpressed in nine tumors (26%). A new cdc25C2 splicing variant lacking exon 4 and 5 was identified in all of the tumors and in 56% of the normal samples. No amplifications or gene rearrangements of these genes were detected. In conclusion, these findings indicate that cdc25 isoforms and splicing variants are differentially regulated in colorectal carcinomas and may participate in the development of these tumors. Additionally, the correlation between cdc25B mRNA levels and the survival of the patients also suggest that the cdc25B isoform may be involved in the progression of the disease.

Placental malaria is associated with cell-mediated inflammatory responses with selective absence of natural killer cells

Immunosuppression, particularly of cell-mediated responses, has classically been thought to play a major role in the increased susceptibility to malaria observed in pregnant women. An immunohistochemical characterization of the inflammatory infiltrate in a group of 41 placentas from women living in a Plasmodium falciparum-hyperendemic area in Tanzania revealed a marked increase in the number of monocytes and macrophages and cytotoxic T cells in the intervillous space of placentas with active malaria infection, compared with noninfected placentas, placentas from women with past infection, and a control group of placentas from Spain. This increase was associated with the severity of the infection. High numbers of monocytes and macrophages were associated with low birth weight. We also detected a complete absence of NK cells in the intervillous space in all placentas. This apparently physiological absence of NK cells may contribute to hindering the clearance of the parasite. These results indicate that placental malaria does not appear to be associated with cell-mediated immunosuppression. The role of the absence of NK cells in increased susceptibility to malaria needs to be further elucidated.

Expression of cyclin D1 and p53 and its correlation with proliferative activity in the spectrum of esophageal carcinomas induced after duodenal content reflux and 2,6-dimethylnitrosomorpholine administration in rats

Alterations in expression of the p53 and cyclin D1 genes have been implicated in the development of esophageal carcinomas in both humans and animal models. We hypothesize that altered expression of cyclin D1 and p53 may be involved in the sequential development of esophageal carcinomas with glandular differentiation induced by the carcinogen, 2,6-dimethylnitrosomorpholine (DMNM) in rats with duodenal content reflux esophagitis. In the present study Sprague-Dawley rats were given DMNM 15 days after performing an esophago-jejunostomy in order to induce chronic duodenal content reflux esophagitis. Expression and localization of p53, cyclin D1 and Ki-67 were examined by immunohistochemical analyses. Twenty of 24 animals developed different types of esophageal carcinomas, including pure squamous carcinoma, adenosquamous carcinoma and pure adenocarcinoma. Undifferentiated basaloid areas were frequently observed in these tumors. Cyclin D1 overexpression was observed in hyperplastic lesions and increased through dysplasia and in undifferentiated areas of infiltrating carcinoma. Cyclin D1 expression coincided with increased Ki-67 expression and decreased along with cell differentiation. The p53 immunohistochemical pattern was parallel to that of cyclin D1, although the percentage of positive cells was usually smaller in all lesions and increased p53 expression started at the dysplastic stage. These findings suggest that overexpression of cyclin D1 may be an early event in DMNM-induced rat esophageal tumorigenesis, causing increased proliferation of esophageal stem cells. Abnormal p53 expression may then be required to promote the development of neoplastic transformation from dysplastic epithelium through invasive phenotype, being more evident in cancer cells with squamous differentiation.

Expression of cathepsins B and S in the progression of prostate carcinoma

Cathepsins B and S (CatB, CatS) are lysosomal cysteine proteases which, among other functions, appear to play a role in cancer progression in different tumor models due to their matrix-degrading properties. To investigate their possible involvement in the development of prostate carcinoma, we immunohistochemically analyzed CatB and CatS in 38 primary human prostatic adenocarcinomas, as well as concomitant high-grade prostatic intra-epithelial neoplasia, nodular hyperplasia and normal tissue. CatB expression was observed in 28 (74%) and CatS in 32 (84%) carcinomas, being concomitant in 24 cases (63%). High-grade intra-epithelial neoplasia expressed CatB in 20/23 cases (87%), and a similar result was obtained for CatS, with expression of both coinciding in 18 cases (78%). In non-neoplastic tissue, strong expression of both proteases was observed in macrophages, inflamed glands and transitional metaplasia, whereas atrophic glands and basal cells of normal glands displayed intense CatB positivity. We conclude that CatB and CatS are often expressed together in neoplastic prostatic cells from pre-invasive to invasive and clinically detectable stages, suggesting a putative role in local invasion, though other functions cannot be ruled out.

The Ljubljana classification: a practical strategy for the diagnosis of laryngeal precancerous lesions

There is no internationally accepted classification of epithelial hyperplastic laryngeal lesions (EHLL). The majority of current classifications follow criteria similar to those commonly used for cervical epithelial lesions. However, the different etiology of laryngeal cancer and its particular clinical and histologic features necessitate a grading system more appropriate to this region. The Ljubljana classification of EHLL was devised in 1971 to cater to this requirement. Detailed criteria for histologic grading in this classification were formulated by a working group on EHLL of the European Society of Pathology in 1999. The system recognizes four grades: simple and abnormal hyperplasia are benign categories; atypical hyperplasia ("risky" epithelium) is potentially malignant, and carcinoma in situ actually malignant. The main features by which the proposed grading system differs from other classifications are: 1. the distinction between benign and potentially malignant lesions; 2. the positive separation of carcinoma in situ from atypical hyperplasia; 3. the lack of prognostic significance for any surface keratin layer. The eventual outcome of EHLL patients so graded justifies the proposal for separating the lesions into a benign group, showing malignant transformation in only 0.9% of cases, from a potentially malignant group showing malignant transformation in 11% of cases. For diagnostically difficult cases, supplementary techniques such as those using morphometry, immunohistochemical and molecular biology are advised to improve the accuracy of diagnosis and predictions of their biological behavior.

[Single fibrous tumor of the parapharyngeal space]

A solitary fibrous tumor (SFT) of the parapharyngeal space presented with local symptoms (hearing loss, nasal obstruction, and paralysis of the soft palate and tongue). SFT, originally described as a mesothelial tumor of the pleura, now is recognized as a mesenchymal tumor that occurs in different locations. In the head and neck region, about 50 cases have been reported. This is the fifth published report of an SFT of the parapharyngeal space. The diagnosis was confirmed by immunohistochemical (positivity for vimentin, CD34, and CD99) and ultrastructural markers (fibroblastic characteristics).

INK4a/ARF locus alterations in human non-Hodgkin's lymphomas mainly occur in tumors with wild-type p53 gene

INK4a/ARF locus codes for two different proteins, p16(INK4a) and p14(ARF), involved in cell cycle regulation. p14(ARF) is considered an upstream regulator of p53 function. To determine the role of these genes in the pathogenesis of human non-Hodgkin's lymphomas we have analyzed exon 1beta, 1alpha, and 2 of the INK4a/ARF locus and p53 gene aberrations in 97 tumors previously characterized for p16(INK4a) alterations. p53 alterations were detected in four of 51 (8%) indolent lymphomas but in 15 of 46 (33%) aggressive tumors. Inactivation of p14(ARF) was always associated with p16(INK4a) alterations. Exon 1beta was concomitantly deleted with exon 1alpha and 2 in eight tumors. One additional lymphoblastic lymphoma showed deletion of exon 1alpha and 2 but retained exon 1beta. No mutations were detected in exon 1alpha and 1beta in any case. Two of the three mutations detected in exon 2 caused a nonsense mutation in the p16(INK4a) reading frame and a missense mutation in the ARF reading frame involving the nucleolar transport domain of the protein. The third mutation was a missense mutation in the p16(INK4a) reading frame, but it was outside the coding region of p14(ARF). Aggressive lymphomas with p14(ARF) inactivation and p53 wild type showed a significantly lower p53 protein expression than tumors with no alteration in any of these genes. In this series of tumors, inactivation of the INK4a/ARF locus mainly occurred in tumors with a wild-type p53 gene because only two lymphomas showed simultaneous aberrations in these genes. Tumors with concomitant alterations of p16(INK4a) and p14(ARF)/p53 genes seem to exhibit a worse clinical behavior than lymphomas with no alterations or isolated inactivation of any of these genes. These findings indicate that p14(ARF) genetic alterations occur in a subset of aggressive NHLs, but they are always associated with p16(INK4a) aberrations. Concomitant disruption of p16(INK4a) and p14(ARF)/p53 regulatory pathways may have a cooperative effect in the progression of these tumors.

Malignant pigmented clear cell epithelioid tumor of the kidney: clear cell ("sugar") tumor versus malignant melanoma

A 73-year-old woman presented with an hemorrhagic kidney tumor initially interpreted as a renal cell carcinoma (RCC). A retroperitoneal recurrence infiltrating the duodenal wall was made up of clear cells, some of which contained Fontana-Masson positive pigment, immunopositive for HMB-45, S-100 protein, actin, and vimentin. The same immunohistochemical profile was retrospectively reproduced in the kidney tumor, where melanosomes were also found ultrastructurally. Lipomatous differentiation was not observed. There was no history of malignant melanoma (MM), or stigmata of tuberous sclerosis. The patient died of disease 5 years after the initial diagnosis. This neoplasm can be considered as a malignant, pigmented, clear-cell epithelioid variant of angiomyolipoma, or "sugar" tumor of the kidney, with the peculiarity of having a previously unreported component of pigmented cells visible on light microscopy. This finding raises the possibility that the exceptional cases of MM reported in renal parenchyma may be pigmented variants of epithelioid angiomyolipoma rather than true MM.

Expression of p27/Kip1 is down-regulated in human prostate carcinoma progression

p27(Kip1) is a cyclin-dependent kinase inhibitor whose down-regulation has been observed in several tumour models, including breast, colorectal, and gastric carcinomas. The purpose of this study was to assess p27(Kip1) protein expression in normal and benign prostatic epithelia as well as the possible existence of abnormalities in prostate carcinoma progression. p27(Kip1) expression was immunohistochemically analysed in 51 normal tissue samples, 11 nodular hyperplasias (NH), 22 high-grade prostatic intraepithelial neoplasias (PIN), 56 localized prostate adenocarcinomas, and 19 metastases. Immunoblotting was performed in ten cases. Normal prostate epithelium and NH showed diffuse and intense p27(Kip1) nuclear expression in most cases. A significant p27(Kip1) down-regulation was observed in many carcinomas when compared with benign epithelium. Forty-seven cases (84 per cent) were low p27(Kip1) expressors (<50 per cent positive cells) and nine cases (16 per cent) were high p27(Kip1) expressors. p27(Kip1) down-regulation was also consistently seen in PIN. Fourteen out of 19 metastases (74 per cent) were low p27(Kip1) expressors. Six metastatic samples had their corresponding primary tumour analysed and three cases showed decreased expression in the metastasis. It is concluded that p27(Kip1) is constitutively expressed in normal and benign prostatic tissue. This expression is clearly down-regulated in neoplastic progression from the preinvasive lesions through invasive carcinoma and metastases and this therefore occurs in early stages of neoplastic transformation.

cdc25a and the splicing variant cdc25b2, but not cdc25B1, -B3 or -C, are over-expressed in aggressive human non-Hodgkin's lymphomas

cdc25 is a family of phosphatases that activate the cyclin-dependent kinases at different points of the cell cycle. cdc25A and -B, but not -C, have been shown to have oncogenic potential. Three different splicing variants of the cdc25B gene, cdc25B1, -B2 and -B3, have also been identified. Experimental studies suggest that cdc25B2 may be more active in vivo than cdc25B3 and -B1, but the relative expression of these splicing variants in human tumors is not known. In this study, we have analyzed the expression of cdc25A, -B1, -B2, -B3 and -C mRNA in 9 non-neoplastic lymphoid samples, 89 non-Hodgki&ngrave;s lymphomas and 9 hematological cancer cell lines by semi-quantitative RT-PCR. cdc25A, -B and -C protein expression was examined by Western blot. Normal peripheral blood lymphocytes and reactive tissues expressed cdc25B1 and -B3 mRNA and very low or undetectable levels of cdc25A, -B2 and -C. High levels of cdc25A and cdc25B2 were found in 35% and 39% of the tumors, respectively, and they were more frequently observed in aggressive than in indolent lymphomas. cdc25B1 and -B3 splice variants were detected in virtually all tumors, and no significant differences were found between high- and low-grade lymphomas. cdc25A and -B protein expression was also higher in aggressive than in indolent lymphomas. cdc25C expression was relatively low in virtually all cases. In conclusion, these findings suggest that cdc25A and -B2, but not cdc25B1, -B3 and -C, are over-expressed in a relatively large number of malignant lymphomas and may participate in the pathogenesis of aggressive variants.

Placental pathology in malaria: a histological, immunohistochemical, and quantitative study

To characterize the histological changes in malarial placentas and their relationship with parity and maternal and cord parasitemias, we conducted a histological study on 1,179 placentas from Ifakara, Tanzania, an area with intense and perennial malaria transmission. Immunohistochemical and quantitative studies for CD45, fibrin, and villous area were performed in 60 cases. Four hundred fifteen placentas (35.2%) showed parasites (active infections); in 303 of them, parasites co-existed with pigment covered by fibrin (chronic infections), and in 112 only parasites were detected (acute infections). Four hundred seventy-five cases (40.3%) showed hemozoin deposition without parasites (past infections). Of women with parasitized placentas, 46.3% did not show parasites in the peripheral blood. Basal membrane thickening (P = .002), fibrinoid necrosis (P = .004), and prominence of syncytial knots (P = .031) were associated with active malarial infection. No quantitative differences for perivillous fibrin deposition or villous area were found. The most significant association with active malarial infection was intervillous infiltration by mononuclear inflammatory cells (P < .001). Chronic infections were associated with the most severe changes, particularly intervillous mononuclear inflammation (OR, 28.7; 95% CI = 16.0 to 51.5, P< .001). Past infections showed only minimal differences with noninfected placentas. Primiparas showed chronic infections more frequently than multiparas (52% v 15%, P < .001). They also showed significantly higher placental parasitemias and intervillous inflammatory infiltrate. In conclusion, placental histology is more sensitive than peripheral blood examination in detecting malarial infection during pregnancy. Most malarial infections recover during pregnancy, leaving few residual changes in the placenta. Intervillous inflammation is the most frequent finding associated with malaria and is especially severe in primiparas, suggesting that mechanisms other than immunosuppression are responsible for the high susceptibility in this group.

Increased number of chromosomal imbalances and high-level DNA amplifications in mantle cell lymphoma are associated with blastoid variants

Mantle cell lymphomas (MCLs) are characterized by 11q13 chromosomal translocations and cyclin D1 overexpression. The secondary genetic and molecular events involved in the progression of these tumors are not well known. In this study, we have analyzed 45 MCLs (32 typical and 13 blastoid variants) by comparative genomic hybridization (CGH). To identify the possible genes included in the abnormal chromosome regions, selected cases were analyzed for P53, P16(INK4a), RB, C-MYC, N-MYC, BCL2, BCL6, CDK4, and BMI-1 gene alterations. The most frequent imbalances detected by CGH were gains of chromosomes 3q (49%), 7p (27%), 8q (22%), 12q (20%), 18q (18%), and 9q34 (16%) and losses of chromosomes 13 (44%), 6q (27%), 1p (24%), 11q14-q23 (22%), 10p14-p15 (18%), 17p (16%), and 9p (16%). High-level DNA amplifications were identified in 11 different regions of the genome, predominantly in 3q27-q29 (13%), 18q23 (9%), and Xq28 (7%). The CGH analysis allowed the identification of regional consensus areas in most of the frequently involved chromosomes. Chromosome gains (P =. 02) and losses (P =.01) and DNA amplifications (P =.015) were significantly higher in blastoid variants. The significant differences between blastoid and typical tumors were gains of 3q, 7p, and 12q, and losses of 17p. CGH losses of 17p correlated with P53 gene deletions and mutations. Similarly, gains of 12q and high-level DNA amplifications of 10p12-p13 were associated with CDK4 and BMI-1 gene amplifications, respectively. One of 2 cases with 8q24 amplification showed C-MYC amplification by Southern blot. Alterations in 2p, 3q, 13, and 18q were not associated with N-MYC, BCL6, RB, or BCL2 alterations, respectively, suggesting that other genes may be the targets of these genetic abnormalities in MCLs. Increased number of gains (0 v 1-4 v >4 gains per case) (P =.002), gains of 3q (P =.02), gains of 12q (P =.03), and losses of 9p (P =. 003) were significantly associated with a shorter survival of the patients. These results indicate that an increased number of chromosome imbalances are associated with blastoid variants of MCLs and may have prognostic significance.

Disregulation of p16MTS1/CDK4I protein and mRNA expression is associated with gene alterations in squamous-cell carcinoma of the larynx

To determine the relationship between p16MTS1/CDK4I expression, gene inactivation and 9p21 loss of heterozygosity (LOH) in the development of laryngeal carcinomas, we have examined p16MTS1/CDK4I protein and mRNA expression in a series of 7 normal and 36 tumoral tissues, and the presence of gene alterations and 9p21 LOH. Fifteen tumors (42%) showed low levels of pl6MTS1/CDK4I protein expression (similar to normal samples), 7 carcinomas (19%) expressed higher levels, and no protein expression was seen in 14 tumors (39%). No gene alterations were detected in 11 of the 15 tumors (73%) with protein levels similar to normal tissues. Most of the cases with absence of protein expression (86%) had gene alterations. Of the 7 tumors with protein over-expression, 4 showed frameshift or point mutations (2 cases each). mRNA analysis showed pl6MTS1/CDK4I -gene expression in 12 of 17 carcinomas examined. Gene alterations were detected in 9 of the 12 mRNA-positive tumors and in 2 of the 5 negative carcinomas. Concordant expression of p16alpha and p16beta transcripts was observed in all tumors. 9p21 LOH was detected in 23 carcinomas, 18 of which (78%) showed associated p16MTS1/CDK4I -gene alterations. These results indicate that disregulation of p16MTS1/CDK4I protein and mRNA expression is a frequent phenomenon in laryngeal carcinomas commonly associated with gene alterations and 9p21 LOH. The relative number of discrepancies between protein and mRNA expression and the presence of genetic alterations indicate that a comprehensive study of the gene including all these parameters may be necessary to assess the role of this gene in the pathogenesis of such tumors.

Ito cell tumor: immunohistochemical investigations of a rare lesion in the liver of mice

In 2 lifespan transgeneration experiments using a total of 4,682 CBA/J mice, we observed uncommon lipomatous lesions in the livers of 8 mice independent of the treatment. Macroscopically, the lesions were described as pale white areas (2) or nodules (6) during necropsy. The lesions ranged from 1 to 15 mm in diameter. Microscopically, the lesions consisted of nodular aggregations of round to spindle-shaped cells that partly caused distinct compression of the adjacent hepatic parenchyma. The tumor cells were smaller than hepatocytes and had dark oval nuclei. Many of the more spherical cells contained clear vacuoles of various sizes, which were shown to be lipid droplets by oil red O staining. In addition to Gomori's silver and Masson's trichrome staining, several immunohistochemical stains were used to characterize the origin of the proliferating cells. Tumor cells were labeled by vimentin, actin, desmin, and proliferating cell nuclear antigen. The 2 cell phenotypes showed similar staining characteristics. Increased amounts of laminin and tenascin, 2 extracellular matrix proteins of the liver, were detected within these neoplasms. Summarizing, we suggest that these tumors are of Ito cell origin.

High-grade carcinoma component in epithelial-myoepithelial carcinoma of salivary glands clinicopathological, immunohistochemical and flow-cytometric study of three cases

Three cases of epithelial-myoepithelial carcinoma (EMC) with coexisting areas of high grade carcinoma are reported. In two of the cases there was a previous recurrence, and in all three patients there had been a sudden increase in size before final surgery. The typical ductal and myoepithelial components of EMC showed the usual biphasic pattern and the expected immunophenotypes, with expression of wide spectrum cytokeratins, Cam 5.2 and EMA in the ductal part, and muscle-specific actin, smooth muscle actin, S-100 protein, vimentin and cytokeratins in the myoepithelial component. These areas also had a low mitotic count and low proliferation rate as measured by immunohistochemistry and by flow cytometry. Conversely, areas of high-grade tumour had the features of a large cell carcinoma, with focal mucin secretion in two cases. This high-grade component showed an epithelial immunophenotype in two cases, and was negative for all tested markers in the third one. The mitotic counts and the proliferation rates were much higher in these anaplastic areas. One of the patients died 3 months after treatment; another developed lymph node metastases 1 year later and was alive after 6 years of follow-up. The third patient was alive without evidence of disease 7 months after wide surgical resection of the tumour. The possibility of anaplastic transformation in EMC makes thorough sampling mandatory in this type of neoplasm.

Expression of p27/Kip1 is down-regulated in human prostate carcinoma progression

p27(Kip1) is a cyclin-dependent kinase inhibitor whose down-regulation has been observed in several tumour models, including breast, colorectal, and gastric carcinomas. The purpose of this study was to assess p27(Kip1) protein expression in normal and benign prostatic epithelia as well as the possible existence of abnormalities in prostate carcinoma progression. p27(Kip1) expression was immunohistochemically analysed in 51 normal tissue samples, 11 nodular hyperplasias (NH), 22 high-grade prostatic intraepithelial neoplasias (PIN), 56 localized prostate adenocarcinomas, and 19 metastases. Immunoblotting was performed in ten cases. Normal prostate epithelium and NH showed diffuse and intense p27(Kip1) nuclear expression in most cases. A significant p27(Kip1) down-regulation was observed in many carcinomas when compared with benign epithelium. Forty-seven cases (84 per cent) were low p27(Kip1) expressors (<50 per cent positive cells) and nine cases (16 per cent) were high p27(Kip1) expressors. p27(Kip1) down-regulation was also consistently seen in PIN. Fourteen out of 19 metastases (74 per cent) were low p27(Kip1) expressors. Six metastatic samples had their corresponding primary tumour analysed and three cases showed decreased expression in the metastasis. It is concluded that p27(Kip1) is constitutively expressed in normal and benign prostatic tissue. This expression is clearly down-regulated in neoplastic progression from the preinvasive lesions through invasive carcinoma and metastases and this therefore occurs in early stages of neoplastic transformation.

Criteria for grading in the Ljubljana classification of epithelial hyperplastic laryngeal lesions. A study by members of the Working Group on Epithelial Hyperplastic Laryngeal Lesions of the European Society of Pathology

AIMS

To validate histological criteria for the grading of epithelial hyperplastic laryngeal lesions (EHHL) (dysplastic laryngeal lesions), we used a system that had been devised and tested in Ljubljana, Slovenia over many years and was felt to be more appropriate to laryngeal pathology than is the commonly-used model of intraepithelial neoplasia in the cervix.

METHODS AND RESULTS

Vocal cord biopsies of 45 patients with a broad spectrum of EHLL were reviewed. Detailed histological criteria were formulated for each of the four grades of EHLL in the Ljubljana classification, comprising simple hyperplasia (benign spinous layer augmentation), abnormal hyperplasia (benign basal and parabasal layer augmentation), atypical hyperplasia (risky for malignancy) and carcinoma in situ (actually malignant, but without invasion).

CONCLUSIONS

Using these criteria a high degree of concordance of histological diagnoses of grading levels for the Ljubljana classification was achieved between the pathologists of the Working Group. The system was found to be more precise for routine diagnostic work than the others in vogue. The different grades of the Ljubljana classification correspond to significantly different levels yielded in each grade by the semiobjective methods of quantitative morphometry and immunohistochemistry.

Possible carcinogenic effects of X-rays in a transgenerational study with CBA mice

A lifetime experiment using 4279 CBA/J mice was carried out to investigate whether the pre-conceptual exposure of sperm cells to X-ray radiation or urethane would result in an increased cancer risk in the untreated progeny, and/or increased susceptibility to cancer following exposure to a promoting agent. The study consisted of four main groups, namely a control group (saline), a urethane group (1 mg/g body wt) and two X-ray radiation groups (1 Gy, 2 Gy). At 1, 3 and 9 weeks after treatment, the males of these four parental groups were mated with untreated virgin females. The offspring of each parental group was divided into two subgroups: one received s.c. urethane (0.1 mg/g body wt once) as a promoter, the other saline, at the age of 6 weeks. All animals were evaluated for the occurrence of tumours. K-ras oncogene and p53 tumour suppressor gene mutations were investigated in frozen lung tumour samples. The female offspring of male parents exposed to X-rays 1 week before their mating showed a trend towards a higher tumour incidence of the haematopoietic system than the F1 controls. In addition, a higher percentage of bronchioloalveolar adenocarcinomas in male offspring born to irradiated paternals mated 1 week after X-ray treatment points to a plausible increased sensitivity of post-meiotic germ cell stages towards transgenerational carcinogenic effects. On the other hand, no increased tumour incidence and malignancy were observed in the offspring born to irradiated paternals mated 3 and 9 weeks after X-ray treatment. Paternal urethane treatment 1, 3 and 9 weeks prior to conception did not result in significantly altered incidence or malignancy of tumours of the lung, liver and haematopoietic tissue in the offspring. K-ras mutations increased during tumour progression from bronchioloalveolar hyperplasia to adenoma. Codon 61 K-ras mutations were more frequent in lung tumours of urethane-promoted progeny from irradiated parents than from control parents. P53 mutations were absent from these lung alterations.

Quality control of three methods for lung tumorigenesis studies

Many variables influence experimental results obtained from laboratory animal studies. One of the variables is tissue sampling for the detection of lesions. The contribution of different levels of sampling to the variability in reported tumour rates was evaluated in a tumorigenesis study using 1872 CBA/J mice. The number of lung neoplasms was estimated by three methods and the results compared. These methods were: 1. counting the macroscopically visible nodules, 2. microscopical examination of macroscopically-detected nodules and one histological section of each lung lobe, cut at the level of the bronchi (common method) and 3. microscopical examination as in method number 2 and additional microscopic examination of step-sections (200 microm interval) of the remaining lung tissue beginning at the level of the bronchi. Analysis using only macroscopic examination (method 1) showed that 40% (747/1872) of the animals had single or multiple nodules (i.e. tumour suspicious areas) in the lungs. When combined with microscopic examination (method 2), primary lung tumours were diagnosed in only 586 animals (31%). Evaluation by gross examination alone therefore gave an apparent overestimation of lung tumours compared to microscopic evaluation of grossly visible nodules. This was found to be due to a significant number of mice having nodules formed by processes other than primary lung tumours (i.e. non-specific inflammation, alveolar histiocytosis, focal hyperplasia of the alveolar epithelium, lymphoma infiltration or tumour metastases). On the other hand, in the more thorough sectioning of the lungs (method 3), primary lung tumours were detected in 712/1872 animals (38%). Additionally, these three different methods influenced the results with regard to the tumour multiplicity in each tumour-bearing animal.

Cell cycle regulators and their abnormalities in breast cancer

One of the main properties of cancer cells is their increased and deregulated proliferative activity. It is now well known that abnormalities in many positive and negative modulators of the cell cycle are frequent in many cancer types, including breast carcinomas. Abnormalities such as defective function of the retinoblastoma gene and cyclin-dependent kinase inhibitors (for example, p16, p21, and p27), as well as upregulation of cyclins, are often seen in breast tumours. These abnormalities are sometimes coincidental, and newly described interplays between them suggest the existence of a complex regulatory web in the cell cycle.

Collagenase-3 expression is associated with advanced local invasion in human squamous cell carcinomas of the larynx

Collagenase-3 (MMP-13) is a matrix metalloproteinase recently identified on the basis of differential expression in normal breast tissues and in breast carcinoma. To date, collagenase-3 expression has been reported only in breast carcinomas and in articular cartilage of arthritic patients; the presence and possible implication of this enzyme in the progression of other malignant tumours are unknown. In this study collagenase-3 mRNA expression has been analysed by northern blot in a series of 35 matched squamous cell carcinomas of the larynx and the corresponding adjacent non-neoplastic tissues. In addition, mRNA expression of membrane type 1-matrix metalloproteinase (MT1-MMP) and gelatinase A, two matrix metalloproteinases which have the ability to activate collagenase-3 in vitro, was also examined in the same cases. No collagenase-3 expression was detected in any of the 35 normal mucosae, but collagenase-3 mRNA was observed in 20 of the 35 carcinomas (57 per cent). Western blot analysis revealed the presence of collagenase-3 protein in those carcinomas with high levels of mRNA expression, whereas no protein was detected in the carcinomas with negative mRNA expression, or in any of the normal tissues. The protein was localized predominantly in tumour epithelial cells. Collagenase-3 expression correlated significantly with better histological differentiation of the tumours (p = 0.026), as well as with advanced local invasion (p = 0.026). Collagenase-3 upregulation was also significantly associated with MT1-MMP and gelatinase A overexpression. These findings suggest that collagenase-3 expression may contribute to the progression of a significant subset of squamous cell carcinomas of the larynx and that its coordinate overexpression with MT1-MMP and gelatinase A may have a cooperative effect in the progression of the tumours.

Intraabdominal desmoplastic small round cell tumor with EWS/ERG fusion transcript

This report describes an intraabdominal small cell tumor in a 37-year-old woman, with clinical, topographic, and morphologic features highly suggestive of the desmoplastic small round cell tumor. Immunohistochemical analysis revealed a polyphenotypic profile consistent with this tumor--positivity for keratin, epithelial membrane antigen, neuron-specific enolase, vimentin, and desmin--but, in addition, a strong membranous immunoreactivity for CD99 (MIC2 protein). Reverse transcription polymerase chain reaction revealed a EWS/ERG fusion transcript characteristic of the Ewing's sarcoma/peripheral primitive neuroectodermal tumor group of tumors, rather than the EWS/WT1 chimeric transcript typical of the desmoplastic small round cell tumor. This is the third report of a hybrid tumor with features of the desmoplastic small round cell tumor and Ewing's sarcoma/peripheral primitive neuroectodermal tumor, and the first one with the EWS/ERG fusion gene. Our case shows the existence of some overlap between these two groups of tumors, which are considered to be histogenetically different, and the need for further studies of molecular characterization of small cell tumors, especially in those with atypical morphologic or immunohistochemical features.

Massive chronic intervillositis of the placenta associated with malaria infection

Massive chronic intervillositis (MCI) is an infrequently recognized placental lesion thought to be of immunologic origin that has been associated with poor fetal outcome. It is characterized by a prominent inflammatory infiltrate in the intervillous space, composed mainly of monocytes and macrophages that can simulate a maternal malignant disorder involving the placenta. The villi are characteristically spared. We report 74 cases of placental malarial infection with morphologic features of MCI. In all cases, the massive inflammatory infiltrate was limited to the intervillous space, which appeared largely obliterated. Increased fibrin deposition and prominent syncytial knots were frequent associated findings. Inflammatory cells were CD45 and CD68 positive, consistent with a monocyte-macrophage population. Some polymorphonuclear leukocytes and scattered T and B lymphocytes were also present. Villi were not inflamed. Malarial pigment was present in all cases, and parasitized maternal erythrocytes were evident in 73 of 74 patients. The histologic pattern of MCI was observed in 17.6% of placentas with malarial parasites. Malarial MCI affected predominantly primigravida women (77%) and was associated with a reduced birth weight, which in 39 (53%) of the infants was less than 2500 g, and a low gestational age. None of the infants with placentas with MCI died in the early neonatal period. Morphologic changes of MCI are seen in a significant percentage of placentas with malarial infection, especially in primigravida women, and are associated with a low birth weight. Malarial infection should therefore be considered in the differential diagnosis of massive intervillous infiltrates.

Evaluation of turnaround times as a component of quality assurance in surgical pathology

OBJECTIVE

As a part of a quality assurance program in anatomic pathology, a study was conducted to determine intralaboratory components of turnaround time according to specimen type, and to compare the present data with results obtained 2 years after implementing the program.

DESIGN

Assessment of intralaboratory turnaround times for surgical pathology reports in a sample of 501 biopsies and surgical specimens during 1992. Comparison between the basal data obtained in 1992 and the final determination in 1994 after the implementation of an improvement action.

SETTING

Surgical specimens and biopsies accessioned at the Department of Anatomic Pathology of a 913-bed acute-care teaching hospital in the city of Barcelona, Spain. STUDY SAMPLES AND PARTICIPANTS: The sample was selected from the total number of biopsies and surgical specimens accessioned on specific days by applying a table of random numbers. Data were collected from the request forms, final report copies, and laboratory registries of turnaround time-points by two resident physicians.

INTERVENTIONS

All relevant information concerning turnaround times was recorded following a standardized questionnaire developed specifically for the study.

MAIN OUTCOME MEASURES

The basal determination for turnaround time for pathologic diagnosis in 1992 was 5.7 days.

RESULTS

The mean turnaround time for the 501 specimens was 6.24 (SD = 3.16; range = 2-27 days). Turnaround times varied substantially according to specimen type. Endoscopic biopsy samples were completed by 5.19 days (SD = 2.18). Bone biopsies were finalized within a mean of 8.11 days of receipt (SD = 3.18). For the diagnosis of lymphoproliferative disorders, most lymph node specimens required special histochemical or immunohistochemical stains. The mean turnaround time for results reporting/results transmittal to the ordering physician varied between 1.14 and 1.66 days. The 1992 annual mean turnaround time for a total of 14,862 surgical pathology specimens was 5.7 days as compared with 4.2 days for a total of 17,931 surgical pathology specimens in 1994.

cdc25 cell cycle-activating phosphatases and c-myc expression in human non-Hodgkin's lymphomas

cdc25A, cdc25B, and cdc25C are a family of human phosphatases that activate the cyclin-dependent kinases at different points of the cell cycle. cdc25A and cdc25B have been shown to have oncogenic potential, and they have been identified as transcriptional targets of c-myc. To determine the role of cdc25 genes in the pathogenesis of human lymphomas and their possible correlation with c-myc deregulation, we have analyzed the expression of cdc25A, cdc25B, and cdc25C and c-myc genes in a series of 63 non-Hodgkin's lymphomas and 8 nonneoplastic lymphoid tissues. The mRNA levels of the three phosphatases in the nonneoplastic tissues were negative or negligible. cdc25B overexpression was detected in 35 tumors (56%). This overexpression was more frequently found in aggressive (81%) than in indolent lymphomas (36%; P < 0.01). cdc25B overexpression was also significantly associated with a higher proliferative activity of the tumors. No cdc25B gene amplification or rearrangements were detected by Southern blot analysis. A biallelic EcoRI polymorphism of cdc25B gene was identified with a similar distribution in patients with lymphoma and in a normal population. cdc25A was overexpressed in three aggressive lymphomas. No detectable cdc25C mRNA levels were seen in any of the tumors. c-myc was overexpressed in 43% of tumors, and it correlated significantly with the presence of cdc25B up-regulation. Twenty-six of 35 (74%) lymphomas with high levels of cdc25B mRNA also showed c-myc overexpression, whereas 27 of 28 (96%) tumors without detectable or with very low cdc25B expression also had undetectable c-myc levels (P < 0.0001). In addition, a significant linear correlation was found between the cdc25B and c-myc mRNA levels (r = 0.575, P < 0.001). These findings suggest that cdc25B overexpression in non-Hodkin's lymphoma may participate in the pathogenesis of aggressive variants, and it may cooperate with c-myc oncogene in the development of these tumors.

p16(INK4a) gene inactivation by deletions, mutations, and hypermethylation is associated with transformed and aggressive variants of non-Hodgkin's lymphomas

The molecular mechanisms underlying the pathogenesis of aggressive lymphomas and the histological transformation of indolent variants are not well known. To determine the role of p16(INK4a) gene alterations in the pathogenesis of non-Hodgkin's lymphomas (NHLs) and the histological progression of indolent variants, we have analyzed the expression, deletions, and mutations of this gene in a series of 112 NHLs. Hypermethylation of the gene was also examined in a subset of tumors with lack of protein expression but without mutations or deletions of the gene. p16(INK4a) gene alterations were detected in 3 out of 64 (5%) indolent lymphomas but in 16 out of 48 (33%) primary or transformed aggressive variants. In the low-grade tumors, p16(INK4a) alterations were detected in 1 (4%) chronic lymphocytic leukemia (hemizygous missense mutation), 1 (6%) follicular lymphoma (homozygous deletion), and 1 (5%) typical mantle cell lymphoma (homozygous deletion). The two later cases followed an aggressive clinical evolution. In the aggressive tumors, p16(INK4a) gene alterations were observed in 2 (29%) Richter's syndromes (2 homozygous deletions), 3 (33%) transformed follicular lymphomas (1 homozygous deletion and 2 nonsense mutations), 3 (43%) blastoid mantle cell lymphomas (2 homozygous and 1 hemizygous deletions), 5 (28%) de novo large-cell lymphomas (1 homozygous deletion and 4 hypermethylations), 2 lymphoblastic lymphomas (2 homozygous deletions), and 1 of 2 anaplastic large cell lymphomas (hypermethylation). Protein expression was lost in all tumors with p16(INK4a) alterations except in the typical chronic lymphocytic leukemia (CLL) with hemizygous point mutation. Sequential samples of the indolent and transformed phase of three cases showed the presence of p16(INK4a) deletions in the Richter's syndrome but not in the CLL component of two cases, whereas in a follicular lymphoma the deletion was present in both the follicular tumor and in the diffuse large-cell lymphoma. In conclusion, these findings indicate that p16(INK4a) gene alterations are a relatively infrequent phenomenon in NHLs. However, deletions, mutations, and hypermethylation of the gene with loss of protein expression are associated with aggressive tumors and they may also participate in the histological progression of indolent lymphomas.

Ki-ras gene mutations and absence of p53 gene mutations in spontaneous and urethane-induced early lung lesions in CBA/J mice

Ki-ras and p53 genes are involved in human lung carcinogenesis; however, the role of these genes in experimental lung tumors is not well known. In our study, the CBA/J mouse strain was used to investigate the presence of Ki-ras and p53 alterations in lung carcinogenesis of spontaneous tumors and tumors induced with high and low doses of urethane (ethyl carbamate). To study the presence of these alterations in the early stages of lung carcinogenesis and in very small lung tumors, restriction fragment length polymorphism and single-strand conformation polymorphism analyses were performed on polymerase chain reaction-amplified DNA from microdissected tumoral and normal lung samples. Ki-ras gene mutations in codons 12 and 61 were detected in all types of lung lesions, even in small and preneoplastic lesions, and their incidence increased with progression from lung hyperplasias (18%) to adenomas (75%) and to carcinomas (80%). Urethane exposure, in both high and low doses, increased the incidence of Ki-ras mutations in lung tumors, especially in adenomas. The presence of Ki-ras gene mutations in very small urethane-induced lung tumors and the absence of hyperplasias among the treated-group lesions may indicate that urethane accelerates tumoral progression. No p53 mutations were detected in exons 5-8 in any of the epithelium-derived lung tumors. Only one p53 mutation in exon 5 was found in a spontaneous lymphoma. Therefore, p53 mutations do not seem to cooperate with Ki-ras gene mutations or represent an alternative molecular pathway in murine carcinogenesis.

Epithelial cell hyperproliferation after biliopancreatic reflux into the esophagus of rats

BACKGROUND

Chronic reflux of duodenal contents into the esophagus of rats produces severe esophagitis and exerts a co-carcinogenic effect on the proliferating cells by enhancing the formation of nitrosamine-induced esophageal carcinomas. We investigated the effect of the different components of the duodenal reflux on the epithelial cell proliferation of the lower esophagus.

METHODS

Sprague-Dawley rats underwent three surgical reflux models (biliopancreatic, pancreatic, and biliary) and a sham operation. Animals were sacrificed at 72 hours, 6 weeks, and 9 weeks after the operation. Histology and cell proliferation, determined by ornithine decarboxylase activity, polyamine (putrescine, spermidine, spermine) levels, and proliferating cell nuclear antigen labeling index of the basal and suprabasal layers, were studied in the distal esophagus.

RESULTS

Both biliopancreatic and pancreatic reflux induced severe esophagitis starting on week 6. Suprabasal proliferating cell nuclear antigen labeling index significantly increased throughout the 9 weeks of the study in the biliopancreatic and pancreatic reflux groups, although this increase was earlier in the former group. Ornithine decarboxylase activity and polyamine levels were significantly increased in the biliopancreatic and pancreatic groups on week 6, decreasing on week 9.

CONCLUSIONS

Increased esophageal cell proliferation after both biliopancreatic and pancreatic reflux into the lower esophagus may therefore be one mechanism by which duodenal-content reflux stimulates esophageal carcinogenesis in experimental animals.

p21WAF1/Cip1 is associated with cyclin D1CCND1 expression and tubular differentiation but is independent of p53 overexpression in human breast carcinoma

p21WAF1/Cip1 is an inhibitor of cdk/cyclin complexes, and thus regulates the cell cycle. p21 is also related to cell differentiation and is regulated by wild-type p53, although p53-independent regulatory pathways have been proposed. In order to analyse p21 expression as well as its relationship with p53 in human breast cancer, an immunohistochemical analysis was undertaken of 77 breast carcinomas, 16 of them with an in situ component; 30 adjacent normal tissue samples; and five non-neoplastic specimens. Forty-four infiltrating carcinomas (57 per cent) were p21-positive. Expression of p21 was also observed in pre-invasive lesions, whereas normal ducts were negative or focally and weakly positive. p21 expression was associated with high histological grade (II + III) (P = 0.017) and poor tubule formation (P = 0.002), and was significantly less frequent in lobular carcinomas (P = 0.0001). p21 positivity also correlated with increased proliferation, but this seemed to be dependent on the histological grade. Twenty carcinomas (26 per cent) showed p53 overexpression, but this was not associated with p21 negativity, suggesting the existence of p53-independent mechanisms for p21 regulation in vivo. Cyclin D1CCND1 expression was analysed in the same series and an association between p21 and cyclin D1 expression was found, since 23 of 26 cyclin D1-positive carcinomas were p21-positive (P < 0.001 ...). In conclusion, p21 is frequently overexpressed in breast carcinomas and this occurs in the early stages of neoplastic progression. This overexpression seems to be independent of p53 status and might be involved in cyclin D1 modulation.

Cancer dissemination during laparoscopic surgery: tubes, gas, and cells

Port-site metastasis has been an unexpected finding after laparoscopic surgery in gastrointestinal cancer patients. No clear explanation exists for this phenomenom. The aims of this study were to evaluate the dissemination pattern in an experimental model of hepatocarcinoma in the rat and summarize current knowledge about the risks and the results of experimental studies on cancer dissemination during laparoscopic surgery. NDA-induced hepatocarcinoma was obtained in Sprague-Dawley rats. Tumors were manipulated during laparoscopy (group 1, n = 11) or laparotomy (group 2, n = 12). A Medline review of all experimental studies about the risk of cancer dissemination during laparoscopic surgery was undertaken. Both models were associated with implants in parietal wounds [1/11 in group 1 (9%) vs. 1/12 in group 2 (8%), p = NS]. Analysis of the current literature confirms that laparoscopy is associated with abdominal cell mobilization, and cells can be recovered in trocars, filtered exhaust gas, and instruments. Postoperative immunosuppression, the biologic aggressiveness of the tumor, and the gas used for laparoscopy also influence tumoral growth. Port-site metastases are secondary to multiple factors, including the technical skill of the surgeon, the biologic properties of the tumors, and local environmental aspects. Undoubtedly, laparoscopy can help disseminate aggressive tumors and should be reserved for diagnostic and staging procedures or for treatment of low-grade malignant tumors. Therapeutic resection, especially of colon cancer, should be restricted to prospective and randomized trials until there are enough hard data to rule out the clinical importance of this potentially severe complication.

Differential expression of galectin 3 and galectin 1 in colorectal cancer progression

BACKGROUND & AIMS

Galectins are beta-galactoside-binding proteins possibly involved in tumor progression. The aim of this study was to determine the pattern of galectin 3 and galectin 1 expression and involvement in colorectal cancer progression.

METHODS

Galectin 3 expression was examined immunohistochemically in 39 samples of normal mucosae, 25 adenomas, 87 carcinomas, and 39 lymph node metastases. Galectin 1 was analyzed in 25 samples of mucosae, 15 adenomas, 25 carcinomas, and 11 metastases. Western blot analysis was also performed.

RESULTS

All normal mucosae showed strong nuclear galectin 3 expression, which was down-regulated in the neoplastic progression, because only 60% of adenomas, 48% of carcinomas, and 44% of metastases were strongly positive (P < 0.0001). Cytoplasmic expression was down-regulated in adenomas (16%) but increased again in carcinomas (64%) (P < 0.0001). Galectin 1 expression was mainly detected in stromal cells and correlated with tumor progression from normal mucosae to adenomas and carcinomas (P < 0.0001).

CONCLUSIONS

Galectin 3 expression is down-regulated in the initial stages of neoplastic progression, whereas a dissociated cytoplasmic expression increases in later phases of tumor progression. Galectin 1 in colorectal mucosa is predominantly a stromal product whose overexpression is associated with the neoplastic progression of colorectal cancer.

p21WAF1/Cip1 expression is associated with cell differentiation but not with p53 mutations in squamous cell carcinomas of the larynx

p21WAF1/Cip1 is a recently identified gene involved in cell cycle regulation through cyclin-CDK-complex inhibition. The expression of this gene in several cell lines seems to be induced by wild-type, but not mutant, p53. p21WAF1/Cip1 expression has been studied at both mRNA and protein levels in a series of 49 normal mucosae and squamous cell carcinomas of the larynx. A significant association was found between mRNA and protein expression in tumours (P < 0.0001). p21WAF1/Cip1 expression was strongly associated with squamous cell differentiation of carcinomas, because six of seven (86 per cent) undifferentiated carcinomas (grade 4) showed very low levels of p21WAF1/Cip1 expression, whereas 41 out of 42 (98 per cent) carcinomas with squamous cell differentiation (grades 1-3) had normal or high levels of p21WAF1/Cip1 expression (P < 0.0001). In addition, p21WAF1/Cip1 expression was topologically related to the squamous differentiation of tumour cells with a distribution similar to that seen in normal squamous epithelium. No correlation was found between p21WAF1/Cip1 expression and the global S-phase of the carcinomas. p53 mutations (exons 5-9) were found in ten carcinomas with p21WAF1/Cip1 expression, but no p53 mutations were detected in three p21WAF1/Cip1-negative tumours. In conclusion, p21WAF1/Cip1 expression is frequently upregulated in squamous cell carcinomas of the larynx and is associated with tumour cell differentiation. p21WAF1/Cip1 expression in these tumours is independent of p53 gene mutations.