A Rare Case of Renal Sarcoma Mimicking Metastatic Osteosarcoma.

Pediatric renal sarcomas are exceedingly rare entities that present diagnostic challenges. We report a remarkable case of a 14-month-old female with an 8 cm right renal mass, accompanied by disseminated bone metastases, posing intricate clinical and histopathological dilemmas. Initial suspicion leaned towards clear cell sarcoma of the kidney (CCSK), however, subsequent histological examination post-chemotherapy revealed high-grade osteosarcoma and further differential considerations arose, including primary renal osteosarcoma and osseous osteosarcoma with secondary renal involvement. Despite inconclusive histology, treatment proceeded with the UH1 chemotherapy protocol for CCSK, incorporating high-dose Methotrexate for potential osteosarcoma, and the patient demonstrated a favorable response to therapy.

Gemcitabine-Induced Myonecrosis Following Hypofractionated Radiation.

Palliative radiation is often used to abate pain and prevent bone fractures in patients with metastatic cancer. Hypofractionation, meaning delivery of larger doses of radiation in each treatment session (fraction), has become the standard of care in most cases. It not only reduces the burden on the medical system and facilitates the relief of symptoms but also enables the maintenance of the continuity of systemic therapy. Radiation recall phenomenon (RRP) is an acute inflammatory reaction in previously irradiated tissues that is provoked by chemotherapeutic drug administration. The incidence, severity, and prognosis of RRP following hypofractionated radiation therapy have not been studied. The symptoms of RRP depend on the radiation field, with the greatest concern associated with mucosal and dermal damage, though other symptoms have also been reported. Here, we describe a case of a 41-year-old woman with metastatic breast cancer (hormone receptor-positive, HER2/neu negative), who received palliative radiation to four other fields along the course of her disease, before her presentation with isolated myonecrosis of the thigh muscles. This RRP occurred four months following the last of two fractions of 8 Gy radiation to this region, given three months apart, and after six courses of cisplatin + gemcitabine. The symptoms improved with cessation of gemcitabine and prolonged administration of non-steroidal anti-inflammatory medications.

α-methylacyl-CoA racemase (AMACR) expression in chordomas differentiates them from chondrosarcomas.

AIMS: Chordomas and chondrosarcomas are malignant mesenchymal tumours with overlapping morphological and immunohistochemical (IHC) characteristics. Our aim was to evaluate the IHC expression of α-methylacyl-CoA racemase (AMACR/P504S), ß-catenin and E-cadherin in chordomas relative to chondrosarcomas and assess the utility of these markers for differential diagnosis. METHODS: Archival sections of 18 chordomas, 19 chondrosarcomas and 10 mature cartilage samples were immunostained and scored for AMACR, ß-catenin and E-cadherin and the relative differential capacity of each marker was calculated. In addition, AMACR mRNA level was assessed in 5 chordomas by RT-PCR and evaluated by comparative CT method. RESULTS: AMACR and ß-catenin stained 88.9% and 94.1% of the chordomas respectively, 21.1% and 10.5% of the chondrosarcomas correspondingly and none of the mature cartilage samples. E-cadherin stained positively 82.4% of the chordomas, 36.8% of the chondrosarcomas and 42.9% of the mature cartilage cases. Both AMACR and ß-catenin showed statistically significant difference between chordomas and chondrosarcomas (p < 0.001 for both), unlike E-cadherin. AMACR was detected at the mRNA level. CONCLUSIONS: AMACR is expressed in most of the chordomas but only in a minority of chondrosarcomas. AMACR may serve as IHC marker of chordoma with differentiating ability comparable to that of ß-catenin.

Histopathological spectrum of bone lesions associated with dental implant failure: osteomyelitis and beyond.

Early or late post-implant placement complications are usually localized infectious/inflammatory processes and treated accordingly. If the healing process does not take place within a reasonable timeframe, the possibility of a pathologic process beyond localized infection/inflammation should be suspected. We describe a radiological/histopathological spectrum of bony lesions ranging from inflammatory to malignant lesions surrounding failed dental implants. Five cases of mandibular dental implant failure that clinically, radiologically and histopathologically appeared to be inflammatory processes are presented. The failure of the dental implants was immediate in two cases and late in the remaining three. The radiological features were essentially similar for all five, and they included radiolucent or mixed radiolucent-radiopaque lesions with poorly defined borders. Three lesions were limited to the area of the failed implant, while the other two extended to a large part of the mandible. The histopathological findings ranged from acute osteomyelitis and chronic osteomyelitis with features of a fibro-osseous-like lesion and occasional rimming of atypical osteoblasts to osteogenic sarcoma that was admixed with a component of osteomyelitis (diagnosis of the latter was achieved only after a series of biopsies). In-depth investigative procedures are imperative in order to establish an accurate diagnosis whenever the histopathological diagnosis is inconsistent with persisting clinical signs and symptoms in bone lesions associated with failed dental implants.

Biomechanical properties of bone treated by magnetic resonance-guided focused ultrasound - an in vivo porcine model study.

The magnetic resonance-guided focused ultrasound (MRgFUS) system uses MR imaging for real-time aiming of thermal ablation of bone and soft tissue tumors. Past clinical studies showed no increase in fracture rate after MRgFUS treatment. The purpose of this study was to determine the effect of MRgFUS treatment on mechanical properties of bone and correlate the effect to histological findings of treated bone. Four fully grown mini-pigs were treated by MRgFUS. Six consecutive right normal ribs were treated in each animal, and the left corresponding ribs served as controls. The animals were sacrificed at pre-set intervals (0, 2, 6 and 12weeks after treatment), and the treated and control bones were extracted. Mechanical properties of each bone were examined using three points bending studies for comparing treated bones to the corresponding controls. Histologic properties using Masson and hematoxylin-eosin stains were also compared. The ratio between treated and control biomechanical properties showed reduction in bone biomechanical properties at 6weeks post-MRgFUS treatment. The mean±SD yield load ratio and maximum ratios were 0.69±0.11 and 0.71±0.13, respectively (both p=0.031). These findings showed some recovery trend at 12weeks after treatment. Histological analysis showed a reduction in mean osteon size at 2weeks after treatment (0.58×10(-3)±0.1×10(-3)mm and 0.16×10(-3)±0.017×10(-3)mm) in control vs. treated bones, respectively (p=0.005). Treatment with the MRgFUS system resulted in a ~30% reduction in mechanical strength at 6weeks post-treatment. The reduction showed a reversible trend, with a 25%-20% decrease in strength at 12weeks post-treatment.

[Clinical-pathologic conference (cpc) - pulmonary insufficiency in Myasthenia Gravis patient].

A 64 year old Myasthenia Gravis patient was admitted with pulmonary insufficiency. The autopsy revealed diffuse Strongyloides stercoralis infection.

Sonographic features of intravascular papillary endothelial hyperplasia (Masson's tumor) in the forearm.

Intravascular papillary endothelial hyperplasia, also known as Masson's tumor, is a benign, vascular lesion in which there is papillary proliferation of endothelial cells. The lesion presents as a palpable soft-tissue mass, often located within normal or dilated vascular spaces, and may be mistaken for a sarcomatous tumor on imaging. We present the case of an intravascular papillary endothelial hyperplasia in the forearm, with a remarkable appearance on color Doppler sonography, and suggest that this entity will be encountered more frequently by sonologists in the future.

The diagnostic role of claudins in serous effusions.

We analyzed the diagnostic role of claudins in effusion cytology in 325 effusions, including 218 ovarian, 49 breast, 15 cervical or endometrial, 10 gastrointestinal, and 8 lung adenocarcinomas and 25 malignant mesotheliomas (MMs). Specimens were analyzed for claudin-1 and claudin-3 expression using immunohistochemical analysis. Ovarian and breast adenocarcinoma were further analyzed for claudin-7 expression. Claudin-1 expression was most frequent in ovarian and cervical or endometrial adenocarcinoma compared with other adenocarcinomas and MMs (P < .001). Claudin-3 expression was comparable in adenocarcinomas of different origin but was absent in MMs (P < .001). Reactive mesothelial cells rarely expressed claudins. Claudin-7 expression was higher in ovarian than in breast adenocarcinoma (P < .001). Our data suggest that expression of claudin-3 or claudin-7 is specific for adenocarcinoma and rules out the diagnosis of cells as mesothelial and that absence of claudin-1 expression excludes ovarian carcinoma as the possible origin of metastatic adenocarcinoma. Claudins may, therefore, be of diagnostic value in effusion cytology.

Scanning electron microscopy of thyroid cells under fully hydrated conditions--a novel technique for a seasoned procedure: a brief observation.

Technical information for handling fine-needle aspiration samples from thyroid lesions for WETSEM electron microscopy is presented. The use of wet SEM technology maintains cytological features of the thyroid cells, in the atmospheric electronic microscope chamber without the need for solidification. Images are presented from normal and pathological thyroid specimens showing subcellular elements unavailable to the cytopathologist by light microscopy. Of 24 samples, 18 were adequate for clinical evaluation. In 16 of these 18 specimens, we could find features compatible with the final histological or cytological diagnosis (post-hoc). In two cases, the cell features were too unique to be interpretable. Because this procedure is relatively simple, there is potential for the use of this technology as an adjunct to light microscopy in clinical and research settings.

Detection of hepatocyte growth factor/scatter factor receptor (c-Met) in axillary drainage after operations for breast cancer using reverse transcriptase-polymerase chain reaction.

BACKGROUND: The diverse biological effects of hepatocyte growth factor/scatter factor (HGF/SF) are mediated by c-Met, which is preferentially expressed on epithelial cells. Met signaling has a role in normal cellular activities, and may be associated with the development and progression of malignant processes. In this study we examined whether Met can be detected in the axillary drainage from patients who underwent conservative operations for breast cancer, and its prognostic significance. METHODS: Thirty-one consecutive patients with invasive ductal carcinoma of the breast suitable for breast-conserving treatment were studied. The output of the drain that had been placed in the axilla during the operation was collected, and the presence of Met and beta-actin were assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) assays. The data were compared with the pathological features of the tumor and the axillary lymph nodes, and with the estrogen receptor and progesterone receptor status. RESULTS: RT-PCR of the axillary lymphatic drainage was positive for Met in 23 (74.2%) of the patients. Positive assays were correlated with increasing tumor size and grade, with capillary and lymphatic invasion, and with lymph node metastasis (P < 0.02, for all comparisons). All 12 patients with axillary lymph node metastases had positive assays for Met, compared with 57.9% of patients without lymph node metastases. All five patients with tumor involvement in the margins of the resection had positive assays for Met in their lymphatic fluid, compared with 18 of 26 positive assays (69.2%) for patients without involved margins (P < 0.04). Finally, Met showed negative correlations with positivity for estrogen receptor and progesterone receptor (P < 0.02). CONCLUSION: Met can be detected in the axillary fluids of patients with breast cancer and its expression in the axillary drainage may have potential as a prognostic factor. This finding might be relevant to therapeutic considerations, because a positive assay for Met in histologically node-negative patients might point to the need to search for node microinvasion or involvement of the excision margins with tumor.

Immunohistochemistry Evaluation of the Effect in Vivo of Tumor Necrosis Factor (TNF)-alpha on Blood Vessel Density in Murine Fibrosarcoma.

PURPOSE: Angiogenesis is essential for tumor growth and metastases, thus bestowing obvious importance upon methodologies which could enable its inhibition. MATERIALS: C57BL/6 female mice bearing a subcutaneous (s.c.) MCA205 fibrosarcoma were used. METHODS: Ten mice were divided equally into two groups. One group was injected intraperitoneally (i.p.) with 10 mug tumor necrosis factor-alpha (TNF-alpha and the other (controls) with Hanks balanced salt solution (HBSS). Tumor growth was monitored at least twice weekly. The number of endothelial cells in the blood microvessels was assessed by immunohistostaining on paraffin-embedded tumor tissue sections using vascular endothelial growth factor (VEGF) and Factor 8 antibodies. Expression of the p53 gene was similarly assessed by immunohistostaining. RESULTS: Injection of 10 mug TNF-alpha into the tumor-bearing mice reduced the number of endothelial cells in the blood microvessels by 46% on day 3 post-injection which was accompanied by an increase (by 37%) in the expression of p53 in these cells. It also inhibited tumor growth compared to the HBSS-injected group starting at 17 days post-cytokine injection. DISCUSSION: The antitumor in vivo effect exerted by TNF-alpha on established murine sarcoma s.c. tumors may be due to an earlier effect of the cytokine on the tumor's blood microvessels, probably through an apoptotic mechanism involving the p53 gene.

Lack of ErbB-2 oncogene product overexpression in soft tissue sarcomas.

The c-erbB-2 gene and its products (also designated HER-2 and c-neu) encode for a 185-kd transmembrane glycoprotein with intracellular tyrosine kinase activity. c-erbB-2 belongs to the epidermal growth factor receptor family, of which there are four known members, and has molecular homology to the epidermal growth factor receptor. It seems that this family is critical in control of growth, differentiation, and mobility of many normal and transformed epithelial cell types. We have looked for overexpression of c-erbB-2 gene product in paraffin-embedded material from 230 cases of soft tissue sarcoma, in order to establish a possible new prognostic marker and a potentially new treatment option. In all the cases, irrespective of the sarcoma histological type, the immunostaining for erbB-2 was negative. Applications of erbB-2 for prognostication as well as the option of receptor targeting by trastuzumab monoclonal antibodies were aborted.