The need for effective radiosentitizing agents: experience in patients with complete pathological response

Chemoradiation therapy is now considered the preferred initial treatment strategy for distal rectal cancer because of the observation of better local disease control and significant tumor downstaging. Downstaging has become an important clinical outcome as patients with complete pathological response are associated with improved survival. Even though radiation alone may result in low local recurrence rates, the use of additional radiosensitizing agents may provide an increase in local disease control in addition to improved tumor regression rates. Several compounds have been investigated in the setting of neoadjuvant multimodality treatment of rectal cancer with variable rates of treatment-related toxicity and complete pathological response. The balance between complete pathological response and toxicity should aid in the management decision for the use of radiosensitizing agents in the neoadjuvant setting for the treatment of rectal cancer. Anti-Cancer Drugs 22: 308-310 (C) 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Estrogen receptor-positive breast carcinomas in younger women are different from those of older women: A pathological and immunohistochemical study

The higher frequency of triple-negative and HER-2-positive tumors detected in younger patients has been suggested as an explanation for the more aggressive tumor types observed in this age group. However, estrogen receptor (ER)-positive tumors are the most frequent subtype of breast carcinomas identified, even in younger patients. In this retrospective study, the morphological and immunohistochemical profiles of ER-positive breast carcinomas from women 35 yrs and younger that were diagnosed between 1997 and 2007 were evaluated. From these cases, 213 were selected based on the availability of pathology reports and paraffin blocks. For comparison, 117 consecutive cases of breast carcinomas diagnosed in patients >60 yrs from 2006 were included. Paraffin-embedded tumors were stained for expression of ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2). Ki-67 antigen, epidermal growth factor receptor (EGFR), cytokeratin 5/6, p53, vimentin, CD117, and p63 using tissue microarrays. ER-positive carcinomas were diagnosed in 120 (56.1%) samples of the younger patient group and in 92 (78.6%) samples of the older patient group. Of these ER-positive carcinomas, 48 (40%) from the younger patient group presented the subtype luminal A, compared with 53 (57.6%) from the older patient group (p=0.01). Tumors from the younger patient group were also associated with increased vascular involvement, co-expression of HER-2, and decreased expression of CD117. These results highlight differences in expression markers and the pathology of ER-positive tumors detected in younger women, with a notable characteristic being co-expression of HER-2. (C) 2010 Elsevier Ltd. All rights reserved.

Clinico-pathological discrepancies in the diagnoses of solid malignancies

Autopsy is a valuable tool in evaluating diagnostic accuracy. Solid malignancies may have a protracted presentation, and diagnosis frequently requires imaging and deep-sited biopsies; clinical and postmortem diagnosis discrepancies may occur in a high rate in these diseases. Here, we analyzed the occurrence of clinico-pathological discrepancies in the diagnoses of solid malignancies in a Brazilian academic hospital. We reviewed charts and autopsy reports of the patients that died from 2001 to 2003 with at least one solid neoplasm. Patients were classified in concordant and discordant cases regarding cancer diagnosis. Discordant cases were categorized in undiagnosed cases (no suspicion of cancer) and in misdiagnosed cases (clinical suspicion of cancer but incompletely diagnosed). Among the 264 patients with a single non-incidental solid neoplasm, the clinico-pathological discrepancy rate was 37.1%. Liver (22.5%), lung (19.4%), and pancreatic cancer (15.3%) were the most frequent malignancies in the discordant group. Misdiagnosis category comprised 68% of the discordant cases, i.e., there was no correct knowledge about the tumor primary site and/or the histological type during life. Our data show that a high rate of discrepancies occurs in solid malignancies. Autopsies may provide the basis for a better understanding of diagnostic deficiencies in different circumstances. (C) 2008 Elsevier GmbH. All rights reserved.

Immunolocalization and pathological alterations following Strongyloides venezuelensis infection in the lungs and the intestine of MHC class I or II deficient mice

The present study, investigated the mechanisms involved in the immune responses of Major Histocompatibility Complex class I or class II knockout mice, following Strongyloides venezuelensis infection. Wild-type C57BL/6 (WT), MHC II(-/-) and MHC I(-/-) mice were individually inoculated with 3000 larvae (U) of S. venezuelensis and sacrificed on days 1, 3, 5, 8, 13 and 21 post-infection (p.i.). Samples of blood, lungs and small intestines were collected. The tissue samples were stained with hematoxylineosin for the pathological analysis. The presence of the parasite was demonstrated by immunoperoxidase analysis. MHC II(-/-) mice presented a significantly higher number of adult worms recovered from the small intestine on day 5 p.i. and presented elevated numbers of eggs in the feces. The infection by S. venezuelensis was completely eliminated 13 days after infection in WT as well as in MHC I(-/-) mice. In MHC II(-/-) mice, eggs and adult worms were still found on day 21 p.i., however, there was a significant reduction in their numbers. In the lung, the parasite was observed in MHC I(-/-) on day 1 p.i. and in MHC II(-/-) mice on days 1 and 5 p.i. In the small intestine of WT mice, a larger number of parasites were observed on day 8 p.i. and their absence was observed after day 13 p.i. Through immunohistochemistry analysis, the parasite was detected in the duodenum of WT on days 5 and 8 p.i., and in knockout mice on days 5, 8 and 13 p.i.; as well as in posterior portions of the small intestine in MHC I(-/-) and MHC II(-/-) on day 13 p.i., a finding which was not observed in WT mice. We concluded that immunohistochemistry analysis contributed to a more adequate understanding of the parasite localization in immunodeficient hosts and that the findings aid in the interpretation of immunopathogenesis in Strongyloides infection. (C) 2008 Elsevier B.V. All rights reserved.

Absence of pathological scarring in the donor site of the scalp in burns: An analysis of 295 cases

Aim: This study aims to describe the incidence of complications on scalp from which a thin split-skin graft was harvested (0.005-0.007 in.) of the donor site in children and adult burn victims. Methods: We reviewed the medical records of 295 burn patients admitted in the Burn Unit of the Clinical Hospital of the Faculty of Medicine of Ribeirao Preto, from January 1998 to December 2007, whose scalps were used as donor site for grafts. Skin-graft thickness varied from 0.005 in. to 0.007 in. The occurrence of pathological healing was evaluated clinically and the time of epithelisation by the main surgeon and a plastic surgeon or a staff nurse. Results: Of the 295 patients whose scalps were used as donor site, 274 were followed from 6 months to 10 years after the procedure (median 18.2 months). Twenty-one patients were lost to follow-up in the first 6 months. No hypertrophic scarring or keloids on the donor site was observed. Five patients (1.82%) presented with folliculitis and two of them were evaluated with small areas of alopecia (0.7%), treated with resection of these areas and primary suture. The average time of epithelisation of the donor site was 7 days. Conclusion: The harvest of thinner split graft from the scalp is a safe procedure. (C) 2009 Elsevier Ltd and ISBI. All rights reserved.

Giardia duodenalis: Pathological alterations in gerbils, Meriones unguiculatus, infected with different dosages of trophozoites

To examine the infection kinetics and development of alterations in the small intestine of gerbils (Meriones unguiculatus), 72 gerbils were divided into six groups (A to F), with A serving as control and the others inoculated with increasing doses of trophozoites from Giardia duodenalis human isolate. The infection kinetics and the development of histopathological alterations were monitored by optical scanning electron microscopy (SEM). A 12-day prepatent period was observed, with intermittent elimination up to day 35 after inoculation. Statistically significant differences were found between the mean number of trophozoites recovered, per group, on the days of sacrifice, and a positive correlation between the moculum dosage and the number of trophozoites recovered. Morphometrically, the villus:crypt ratio showed a drop in all the groups when compared with the control group. SEM revealed an increase in mucus production in the inoculated animals and the presence of trophozoite clusters at the top and base of the villi. The dosage of trophozoite inoculum does not interfere in the ability for infection to occur or in the development of histopathological alterations generated by intestinal colonization. (c) 2007 Elsevier Inc. All rights reserved.

NO EVIDENCE OF PATHOLOGICAL AUTOIMMUNITY FOLLOWING MYCOBACTERIUM LEPRAE HEAT-SHOCK PROTEIN 65-DNA VACCINATION IN MICE

Heat-shock proteins (HSPs) are currently one of the most promising targets for the development of immunotherapy against tumours and autoimmune disorders. This protein family has the capacity to activate or modulate the function of different immune system cells. They induce the activation of monocytes, macrophages and dendritic cells, and contribute to cross-priming, an important mechanism of presentation of exogenous antigen in the context of MHC class I molecules, These various immunological properties of HSP have encouraged their use in several clinical trials. Nevertheless, an important issue regarding these proteins is whether the high homology among HSPs across different species may trigger the breakdown of immune tolerance and induce autoimmune diseases. We have developed a DNA vaccine codifying the Mycobacterium leprae Hsp65 (DNAhsp65), which showed to be highly immunogenic and protective against experimental tuberculosis. Here, we address the question of whether DNAhsp65 immunization could induce pathological autoimmunity in mice. Our results show that DNAhsp65 vaccination induced antibodies that can recognize the human Hsp60 but did not induce harmful effects in 16 different organs analysed by histopathology up to 210 days after vaccination. We also showed that anti-DNA antibodies were not elicited after DNA vaccination. The results are important for the development of both HSP and DNA-based immunomodulatory agents.

Experimental infection with Rangelia vitalii in dogs: Acute phase, parasitemia, biological cycle, clinical-pathological aspects and treatment

Recently we conducted the molecular characterization of Rangelia vitalii, a protozoan with high pathogenicity for young dogs in southern Brazil. To date, the descriptions of the disease have been restricted to natural infection cases. Therefore, this study aimed to evaluate the parasitemia, biological cycles and clinical-pathological findings in dogs experimentally infected with R. vitalii in the acute phase of disease, and also aimed to test a therapeutic protocol based on the diminazene aceturate. For this study, we used 12 young dogs (females), separated into two groups. Group A was composed of healthy dogs, not-infected (n = 5), and Group B consisted of animals infected with R. vitalii (n = 7). After infection, the animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite 5 days post-infection (PI). Parasitemia increased progressively in these animals and had the highest peak of circulating parasites between 9 and 11 days PI. Subsequently, the parasitemia reduced and the protozoan was seen inside the leukocytes in days 17, 19 and 21 PI. The most prominent clinical signs observed at the 20 day PI of experiment were lethargy, fever and anorexia. We observed a decrease of hematocrit of infected animals compared with not-infected dogs, featuring a moderate anemia. Pathological evaluation of one dog in Group B at day 21 PI revealed splenomegaly, hepatomegaly, lymphadenopathy, and hemorrhages at necropsy. Histological examination showed only follicular hyperplasia in the spleen and lymph nodes, and the etiologic agent in the vascular endothelium. At 21 days PI, it was performed the treatment of dogs in Group B (n = 6) with a single dose of diminazene aceturate, which showed a curative efficacy of 100% in cleaning R. vitalii from blood of infected dogs. (C) 2011 Elsevier Inc. All rights reserved.

Finite element studies of the mechanical behaviour of the diaphragm in normal and pathological cases

The diaphragm is a muscular membrane separating the abdominal and thoracic cavities, and its motion is directly linked to respiration. In this study, using data from a 59-year-old female cadaver obtained from the Visible Human Project, the diaphragm is reconstructed and, from the corresponding solid object, a shell finite element mesh is generated and used in several analyses performed with the ABAQUS 6.7 software. These analyses consider the direction of the muscle fibres and the incompressibility of the tissue. The constitutive model for the isotropic strain energy as well as the passive and active strain energy stored in the fibres is adapted from Humphrey's model for cardiac muscles. Furthermore, numerical results for the diaphragmatic floor under pressure and active contraction in normal and pathological cases are presented.

Clinical and Pathological Findings in Women with Fabry Disease

Introduction. Fabry disease is a rare metabolic disorder caused by the genetic deficiency of the lysosomal hydrolase alpha-galactosidase A, located on chromosome X. Females with the defective gene are more than carriers and can develop a wide range of symptoms. Nevertheless, disease symptoms generally occur later and are less severe in women than in men. The enzyme deficiency manifests as a glycosphingolipidosis with progressive accumulation of glycosphingolipids and deposit of inclusion bodies in lysosomes giving a myelinlike appearance. Patients and Methods. Records of renal biopsies performed on adults from 1st January 2008 to 31st August 2011, were retrospectively examined at the Renal Pathology Laboratory. We retrieved biopsies diagnosed with Fabry disease and reviewed clinical and laboratory data and pathology findings. Results. Four female patients with a mean age of 49.3±4.5 (44-55) years were identified. The mean proteinuria was 0.75±0.3 g/24h (0.4-1.2) and estimated glomerular filtration rate (CKD EPI equation) was 71±15.7 ml/min/1.73m2 (48-83). Three patients experienced extra-renal organ involvement (cerebrovascular, cardiac, dermatologic, ophthalmologic and thyroid) with distinct severity degrees. Leukocyte α-GAL A activity was below normal range in the four cases but plasma and urinary enzymatic activity was normal. Light microscopy showed predominant vacuolisation of the podocyte cytoplasm and darkly staining granular inclusions on paraffin and plastic-embedded semi-thin sections. Electron microscopy showed in three patients the characteristic myelin-like inclusions in the podocyte cytoplasm and also focal podocyte foot process effacement. In one case the inclusions were also present in parietal glomerular cells, endothelial cells of peritubular capillary and arterioles. Conclusion. Clinical signs and symptoms are varied and can be severe among heterozygous females with Fabry disease. Intracellular accumulation of glycosphingolipids is a characteristic histologic finding of Fabry nephropathy. Since this disease is a potentially treatable condition, its early identification is imperative. We should consider it in the differential diagnosis of any patient presenting with proteinuria and/or chronic kidney disease, especially if there is a family history of kidney disease.

EXPERIMENTAL INFECTION WITH Toxocara cati IN PIGS: MIGRATORY PATTERN AND PATHOLOGICAL RESPONSE IN EARLY PHASE

Experimental inoculations of approximately 100,000 infective Toxocara cati larval eggs were done in twelve pigs. The T. cati eggs used for inoculation were collected from cat's feces. Another group of three pigs served as an uninfected control. Groups of infected pigs were euthanized at seven, 14, 21, and 28 days post-inoculation (dpi). Tissue samples were taken for digestion and histopathology changes in early phase. The number of larvae recovered from the lungs peaked at seven and 14 dpi and were also present at 21, and 28 dpi. Larvae of T. cati were present in the lymph nodes of the small and large intestine at seven, 14, and 28 dpi and at seven, 14, 21, and 28 dpi respectively. In other studied tissues, no larvae or less than one larva per gram was detected. The pathological response observed in the liver and lungs at seven and 14 dpi, showed white spots on the liver surface and areas of consolidation were observed in the lungs. The lungs showed an inflammatory reaction with larvae in center at 28 dpi. In the liver we observed periportal and perilobular hepatitis. The lymph nodes of the intestines displayed eosinophil lymphadenitis with reactive centers containing parasitic forms in some of them. The granulomatous reaction was not observed in any tissues. The role of the other examined tissues had less significance. The relevance of this parasite as an etiological agent that leads to disease in paratenic hosts is evident.

Neuroendocrine Tumours of the Female Genital Tract: a Case-Based Imaging Review with Pathological Correlation

BACKGROUND: Both primary and secondary gynaecological neuroendocrine (NE) tumours are uncommon, and the literature is scarce concerning their imaging features. METHODS: This article reviews the epidemiological, clinical and imaging features with pathological correlation of gynaecological NE tumours. RESULTS: The clinical features of gynaecological NE tumours are non-specific and depend on the organ of origin and on the extension and aggressiveness of the disease. The imaging approach to these tumours is similar to that for other histological types and the Revised International Federation of Gynecology and Obstetrics (FIGO) Staging System also applies to NE tumours. Neuroendocrine tumours were recently divided into two groups: poorly differentiated neuroendocrine carcinomas (NECs) and well-differentiated neuroendocrine tumours (NETs). NECs include small cell carcinoma and large cell neuroendocrine carcinoma, while NETs account for typical and atypical carcinoids. Cervical small cell carcinoma and ovarian carcinoid are the most common gynaecological NE tumours. The former typically behaves aggressively; the latter usually behaves in a benign fashion and tends to be confined to the organ. CONCLUSION: While dealing with ovarian carcinoids, extra-ovarian extension, bilaterality and multinodularity raise the suspicion of metastatic disease. NE tumours of the endometrium and other gynaecological locations are very rare. TEACHING POINTS: • Primary or secondary neurondocrine (NE) tumours of the female genital tract are rare. • Cervical small cell carcinoma and ovarian carcinoids are the most common gynaecological NE tumours. • Cervical small cell carcinomas usually behave aggressively. • Ovarian carcinoids tend to behave in a benign fashion. • The imaging approach to gynaecological NE tumours and other histological types is similar.