Parosteal osteosarcoma with low grade chondrosarcoma and liposarcoma components. A rare histologic variant. Case report and literature review.

INTRODUCTION: conventional parosteal osteosarcoma is an uncommon malignant bone tumor, comprising 4% of all osteosarcomas. Although rare, parosteal osteosarcoma is the most common type of osteosarcoma of the bone surface. We present the clinical, histological and imaging characteristics of a rare histologic variant of a parosteal osteosarcoma, review the literature and emphasize the importance of radio-pathological correlation as well as the interpretation of a representative biopsy in order to obtain the correct diagnosis. CASE REPORT: a 36-year old woman began her condition one year prior to admission to the hospital with increased volume in the left knee and pain. Image studies showed a juxtacortical heterogeneous tumor localized on the posterior surface of the distal femoral metaphysis. An incisional biopsy was performed, with the diagnosis of a Parosteal Osteosarcoma and a wide surgical resection was undertaken. According to the findings of the surgical specimen, the diagnosis of a Parosteal Osteosarcoma with low grade chondrosarcoma and liposarcoma components was made. The knowledge of this rare parosteal osteosarcoma variant can lead the orthopedic oncologists to avoid overlooking the adipose component and provide adequate surgical margins. CONCLUSION: we present the clinical, histological and imaging characteristics of a Parosteal Osteosarcoma with low grade liposarcoma and chondrosarcoma components.

INTRODUCCIÓN: el osteosarcoma parosteal convencional es un tumor óseo maligno poco común, que comprende el 4% de todos los osteosarcomas. Aunque es poco común, el osteosarcoma parosteal es el tipo más común de osteosarcoma de la superficie ósea. Presentamos las características clínicas, histológicas y de imagen de una variante histológica rara de un osteosarcoma parosteal, revisamos la literatura y enfatizamos la importancia de la correlación radio-patológica, así como la interpretación de una biopsia representativa para obtener el diagnóstico correcto. REPORTE DE CASO: mujer de 36 años inició su cuadro un año antes de su ingreso al hospital con aumento de volumen en rodilla izquierda y dolor. Los estudios de imagen mostraron una tumoración heterogénea yuxtacortical localizada en la superficie posterior de la metáfisis femoral distal. Se realizó biopsia incisional, con diagnóstico de osteosarcoma parosteal y se realizó resección quirúrgica amplia. De acuerdo con los hallazgos de la pieza quirúrgica se realizó el diagnóstico de osteosarcoma parosteal con componentes de condrosarcoma y liposarcoma de bajo grado. El conocimiento de esta rara variante de osteosarcoma parosteal puede llevar a los ortopedistas oncólogos a considerar otros componentes y proporcionar márgenes quirúrgicos adecuados. CONCLUSIÓN: presentamos las características clínicas, histológicas y de imagen de un osteosarcoma parosteal con componentes de liposarcoma y condrosarcoma de bajo grado.

Ligamentum flavum in lumbar spinal stenosis, disc herniation and degenerative spondylolisthesis. An histopathological description / Ligamento amarillo en estenosis lumbar espinal, hernia de disco y espondilolistesis degenerativa. Una descripción histopatológica

Abstract: Introduction: Changes in ligamentum flavum (LF) related to degeneration are secondary to either the aging process or mechanical instability. Previous studies have indicated that LF with aging shows elastic fiber loss and increased collagen content, loss of elasticity may cause LF to fold into the spinal canal, which may further narrow of the canal. Material and methods: A total of 67 patients operated with the surgical indications of lumbar spinal stenosis (LSS), lumbar disc herniation (LDH) and lumbar degenerative spondylolisthesis (LDS) were included. LF samples were obtained from patients who had LSS (39), LDH (22) and LDS (6). Specimens were examined with regard to chondroid metaplasia, calcification, fragmentation of collagen fibers, cystic degeneration, fibrillar appearence, and hypercellularity. Results: The most frequent histopathological changes were hyalinization and fragmentation of collagen fibers occur in 34%, neovascularization in 40.3% and irregular arrangement of elastic fibers is the most prevalent change with 56.7% of the total samples. There is a difference in the presence of certain changes in the LF according to the diagnosis, being statistically significant for fragmentation of collagen fibers (p = 0.045), cystic degeneration (p = 0.001), fibrillar appearance (p = 0.007) and hypercellularity (p = 0.005) all of these, being more prevalent in LDS group. LHD group presented fragmentation of collagen fibers in 45.5% (p = 0.045) and fibrillar appearance in 4.5% (p = 0.009). Conclusions: There is not evidence of cellular hyperthophy in the histhopatological analyses, thickening of the LF can be seen by bulking of LF followed by collapse of motion segment.

Resumen: Introducción: Los cambios en el ligamento flavum (LF) relacionados con la degeneración son secundarios al proceso de envejecimiento o a la inestabilidad mecánica. Estudios anteriores han indicado que LF con envejecimiento muestra pérdida de fibras elásticas y aumento del contenido de colágeno, la pérdida de elasticidad puede hacer que el LF se pliegue en el canal espinal, disminuyendo su espacio. Material y métodos: Se incluyeron 67 pacientes operados de estenosis lumbar espinal (LSS), hernia de disco lumbar (LDH) y espondilolistesis degenerativa (LDS). Se obtuvieron muestras de LF de pacientes que tenían LSS (39), LDH (22) y LDS (6). Se examinaron especímenes con respecto a metaplasia condroide, calcificación, fragmentación de fibras de colágeno, degeneración quística, apariencia fibrilar e hipercelularidad. Resultados: Los cambios histopatológicos más frecuentes fueron la hialinización y la fragmentación de las fibras de colágeno (34%), neovascularización en 40.3%, y la disposición irregular de las fibras elásticas es el cambio más frecuente con 56.7% del total de muestras. Existe una diferencia en la presencia de cambios en el LF, de acuerdo con el diagnóstico, siendo estadísticamente significativo para la fragmentación de las fibras de colágeno (p = 0.045), la degeneración quística (p = 0.001), la apariencia fibrilar (p = 0.007) y la hipercelularidad (p = 0.005) todos ellos, siendo más frecuentes en el grupo LDS. El grupo LHD presentó fragmentación de las fibras de colágeno en 45.5% (p = 0.045) y la apariencia fibrilar en 4.5% (p = 0.009). Conclusiones: No hay evidencia de hipertrofia celular en los análisis histopatológicos, el engrosamiento del LF se puede ver por abultamiento del mismo, seguido de colapso del segmento de movimiento.

Ligamentum flavum in lumbar spinal stenosis, disc herniation and degenerative spondylolisthesis. An histopathological description.

INTRODUCCIÓN: Los cambios en el ligamento flavum (LF) relacionados con la degeneración son secundarios al proceso de envejecimiento o a la inestabilidad mecánica. Estudios anteriores han indicado que LF con envejecimiento muestra pérdida de fibras elásticas y aumento del contenido de colágeno, la pérdida de elasticidad puede hacer que el LF se pliegue en el canal espinal, disminuyendo su espacio. MATERIAL Y MÉTODOS: Se incluyeron 67 pacientes operados de estenosis lumbar espinal (LSS), hernia de disco lumbar (LDH) y espondilolistesis degenerativa (LDS). Se obtuvieron muestras de LF de pacientes que tenían LSS (39), LDH (22) y LDS (6). Se examinaron especímenes con respecto a metaplasia condroide, calcificación, fragmentación de fibras de colágeno, degeneración quística, apariencia fibrilar e hipercelularidad. RESULTADOS: Los cambios histopatológicos más frecuentes fueron la hialinización y la fragmentación de las fibras de colágeno (34%), neovascularización en 40.3%, y la disposición irregular de las fibras elásticas es el cambio más frecuente con 56.7% del total de muestras. Existe una diferencia en la presencia de cambios en el LF, de acuerdo con el diagnóstico, siendo estadísticamente significativo para la fragmentación de las fibras de colágeno (p = 0.045), la degeneración quística (p = 0.001), la apariencia fibrilar (p = 0.007) y la hipercelularidad (p = 0.005) todos ellos, siendo más frecuentes en el grupo LDS. El grupo LHD presentó fragmentación de las fibras de colágeno en 45.5% (p = 0.045) y la apariencia fibrilar en 4.5% (p = 0.009). CONCLUSIONES: No hay evidencia de hipertrofia celular en los análisis histopatológicos, el engrosamiento del LF se puede ver por abultamiento del mismo, seguido de colapso del segmento de movimiento.

INTRODUCTION: Changes in ligamentum flavum (LF) related to degeneration are secondary to either the aging process or mechanical instability. Previous studies have indicated that LF with aging shows elastic fiber loss and increased collagen content, loss of elasticity may cause LF to fold into the spinal canal, which may further narrow of the canal. MATERIAL AND METHODS: A total of 67 patients operated with the surgical indications of lumbar spinal stenosis (LSS), lumbar disc herniation (LDH) and lumbar degenerative spondylolisthesis (LDS) were included. LF samples were obtained from patients who had LSS (39), LDH (22) and LDS (6). Specimens were examined with regard to chondroid metaplasia, calcification, fragmentation of collagen fibers, cystic degeneration, fibrillar appearence, and hypercellularity. RESULTS: The most frequent histopathological changes were hyalinization and fragmentation of collagen fibers occur in 34%, neovascularization in 40.3% and irregular arrangement of elastic fibers is the most prevalent change with 56.7% of the total samples. There is a difference in the presence of certain changes in the LF according to the diagnosis, being statistically significant for fragmentation of collagen fibers (p = 0.045), cystic degeneration (p = 0.001), fibrillar appearance (p = 0.007) and hypercellularity (p = 0.005) all of these, being more prevalent in LDS group. LHD group presented fragmentation of collagen fibers in 45.5% (p = 0.045) and fibrillar appearance in 4.5% (p = 0.009). CONCLUSIONS: There is not evidence of cellular hyperthophy in the histhopatological analyses, thickening of the LF can be seen by bulking of LF followed by collapse of motion segment.

Osteogenic potential of murine periosteum for critical-size cranial defects.

Tissue engineering of bone has combined bespoke scaffolds and osteoinductive factors to maintain functional osteoprogenitor cells, and the periosteum has been confirmed as a satisfactory source of osteoblasts. Suitable matrices have been identified that support cell proliferation and differentiation, including demineralised bone matrix (both compatible and osteoinductive) and acellular human dermis. We have evaluated the osteogenic potential of an osteogenic unit, developed by combining periosteum, demineralised bone matrix, and acellular human dermis, in rodents with critical-size cranial defects. Briefly, remnants from the superior maxillary periosteum were used to harvest cells, which were characterised by flow cytometry and reverse retrotranscriptase-polymerase chain reaction (RT-PCR). Cells were cultured into the osteogenic unit and assessed for viability before being implanted into 3 rodents, These were compared with the control group (n=3) after three months. Histological analyses were made after staining with haematoxylin and eosin and Von Kossa, and immunostaining, and confirmed viable cells that stained for CD90, CD73, CD166, runt-related transcription factor, osteopontin, and collagen type I in the experimental group, while in the control group there was only connective tissue on the edges of the bone in the injury zone. We conclude that osteogenic unit constructs have the osteogenic and regenerative potential for use in engineering bone tissue.

Ochronotic arthropathy as a paradigm of metabolically induced degenerative joint disease. A case-based review.

Alkaptonuria is a rare, hereditary metabolic disorder in which a deficiency in the homogentisate 1,2-dioxygenase enzyme results in an accumulation of homogentisic acid. Deposition of excess homogentisic acid in different intra- and extra-articular structures with high content of connective tissue causes brownish-black pigmentation and weakening, ultimately resulting in tissue degeneration and finally osteoarthritis. Ochronotic arthropathy is considered a rapidly progressive, disabling condition in which weight-bearing joints and the thoracolumbar spine are predominantly affected. Patients often require multiple joint replacements, such as in the case of the patient presented here. At present, there is no definitive cure for ochronosis, and management is predominantly symptomatic.

Artritis seudoséptica presenta sinovitis por cuerpo extraño en un paciente con gota / Pseudoseptic arthritis with foreign body synovitis in a patient with gout

La monoartritis es un reto diagnóstico para el clínico, ya que es extensa la lista de patologías asociadas. En pacientes con diagnóstico establecido de enfermedad articular inflamatoria, se acepta que la monoartritis corresponde a la exacerbación de la enfermedad de base; sin embargo, ignorar el abordaje sistematizado de las monoartritis puede generar omisiones e implicaciones diagnósticas erróneas. En este reporte se analiza el abordaje de un caso de artritis seudoséptica, simulando un ataque agudo de artritis por urato monosódico recurrente en un paciente con retención de cuerpo extraño intraarticular.

Monoarthritis is a diagnostic challenge for the clinician, as the list of associated conditions is quite long. It is accepted that in patients with a diagnosis of inflammatory joint disease monoarthritis represents exacerbation of the underlying disease. However, ignoring the systematized approach to monoarthritides may lead to omissions and mistaken diagnostic implications. This report describes the approach to a case of pseudoseptic arthritis that mimicked an acute episode of recurrent arthritis due to monosodium urate in a patient with retention of an intraarticular foreign body.

[Pseudoseptic arthritis with foreign body synovitis in a patient with gout]. / Artritis seudoséptica presenta sinovitis por cuerpo extraño en un paciente con gota.

Monoarthritis is a diagnostic challenge for the clinician, as the list of associated conditions is quite long. It is accepted that in patients with a diagnosis of inflammatory joint disease monoarthritis represents exacerbation of the underlying disease. However, ignoring the systematized approach to monoarthritides may lead to omissions and mistaken diagnostic implications. This report describes the approach to a case of pseudoseptic arthritis that mimicked an acute episode of recurrent arthritis due to monosodium urate in a patient with retention of an intraarticular foreign body.

[Pelvic chondroblastoma in an adolescent. New treatment approach]. / Condroblastoma en la pelvis de un adolescente. Nuevo enfoque de tratamiento.

Surgical management of tumors located in the spine and the pelvis involves greater difficulty. Moreover, these tumors are usually very large and vascularized. Preoperative embolization of the internal iliac artery is a relatively safe procedure that may reduce the risk of bleeding and local recurrence in the case of benign tumors. Chondroblastoma is a tumor that is rarely located in the pelvis; its more frequent location is the triradiate cartilage. We describe a case of a chondroblastoma with a relapsing aneurysmal cystic component in the acetabulum of an adolescent patient. Treatment consisted of embolization of the internal iliac artery, fluid hyperthermia, hydrogen peroxide and bone marrow application. The patient was found to be asymptomatic at the 5-year postoperative follow-up. The technetium (99mTc) sestamibi scan was negative for tumor activity and found no lung metastases.

Ulcerative colitis in husband and wife. First report in Mexico.

The prevalence of inflammatory bowel disease in Mexico is low. The occurrence in familial cases has been attributed to genetic influences. We described the first report of inflammatory bowel diseases in one pairs of husband-wife in Mexico. According with characteristics of this case, we can speculate that the environmental and infectious etiology might play some role in the development of IBD.

Endocannabinoid receptor CB2 in nonalcoholic fatty liver disease.

BACKGROUND AND AIM: Fatty infiltration and fibrosis are major issues in chronic liver disease. Recent reports suggest a role for the endocannabinoid system in these processes. AIM: To characterize localization and expression of CB2 in normal liver and nonalcoholic fatty liver. METHODS: We studied 64 liver biopsies: eight were considered normal; 56 had a diagnosis of nonalcoholic fatty liver disease (NAFLD); 32 with nonalcoholic steatosis and 24 nonalcoholic steatohepatitis (NASH). CB2 immunolocalization was studied in 38 samples in paraffin blocks using immunohistochemistry, and a computerized semiquantitative analysis was carried out. CB2 mRNA expression was assessed through RT-PCR in 26 frozen liver samples and the ratio CB2/beta-actin was used to evaluate differences between groups. Statistical analysis was performed with central tendency measures and the Mann-Whitney U-test. We considered as significant differences those with a P-value <0.05. RESULTS: Neither parenchymal nor nonparenchymal cells in normal liver tissue react towards anti-CB2 antibodies. All the samples from patients with steatosis and nonalcoholic steatohepatitis showed hepatocellular immunoreactivity. Cholangiocytes were positive only in the NAFLD group. Normal liver tissue showed a normalized CB2/beta-actin ratio of 0.001+/-0.01, steatosis 6.52+/-17.3 (P=0.05 vs normal) and NASH 6.49+/-12.2 (P=0.06 vs normal and P=0.6 vs steatosis). CONCLUSION: CB2 receptors are expressed by hepatocytes in nonalcoholic fatty liver disease but not in normal liver.

Artifactual signet-ring-like cells in endoscopic biopsy of gastric lymphoma.

OBJECTIVE: To describe the morphologic characteristics of neoplastic lymphocytes with shrinkage artifact of cytoplasm secondary to formalin fixation and/or necrosis, which simulate carcinoma signet-ring cells in endoscopic biopsy. DESIGN: Sixty-eight endoscopic biopsies with gastric lymphoma were studied retrospectively. We selected those biopsies in which artifactual signet-ring-like cells were the main histologic feature and were confused with adenocarcinoma. Mucin stains were performed on all specimens. To support their B-cell phenotype, immunohistochemical study with leukocyte common antigen (CD45), pan B-cell marker L26, keratin, and carcinoembryonic antigens were performed. The diagnosis of gastric lymphoma was confirmed in gastrectomy specimens. SETTING: The distinction between poorly differentiated adenocarcinoma and gastric lymphoma in endoscopic biopsies is sometimes difficult owing to the morphologic similarities that these neoplasias can share and the small amount of tissue obtained by this technique. An additional factor that may contribute to this confusion is the presence of artifactual lymphocytes resembling signet-ring cells. RESULTS: Three (4%) of the 68 biopsies showed artifactual lymphocytes in most or all the tissue fragments that resembled carcinoma signet-ring cells. These biopsies showed massive substitution of gastric glands by lymphomatous infiltrate. Crush artifact of neoplastic lymphocytes was observed in many fields. Necrosis, inflammation, and epithelial erosion were prominent findings. Mucin stains were negative, and immunohistochemical studies were positive for leukocyte common antigen and B-cell marker L26 in two of the three cases. CONCLUSIONS: We conclude that if a poorly differentiated neoplasm consistent with signet ring adenocarcinoma is found in an endoscopic biopsy with artifactual changes, the diagnosis of gastric lymphoma must be excluded using histochemical and immunohistochemical studies.

Hepatitis C: a disease with a wide morphological spectrum?

We describe the pathological findings of 50 biopsies of Mexican (Mestizo, or mixed race, usually Indian and white heritage) patients with hepatitis C infection confirmed by a second generation test. Although half of the patients were asymptomatic, the histological examination revealed advanced stages of disease. Chronic active hepatitis was found in 26 cases, cirrhosis in 23, and acute hepatitis in one case. Common histological changes included steatosis, lymphoid aggregates, and apoptotic bodies, whereas indisputable bile duct damage was observed in only four cases. Comparison with other series in which different types of populations were analyzed revealed a wide morphological spectrum with respect to some histological changes and the type of hepatitis reported. The apparently contradictory results found in the literature indicate the need to apply universal histological criteria in biopsies of patients with hepatitis C.

[Clear-cell eccrine carcinoma of the plantar region. Follow-up of a case using histochemistry, immunohistochemistry, and flow cytometry]. / Carcinoma ecrino de células claras en región plantar. Seguimiento de un caso por histoquímica, immunohistoquímica y citometría de flujo.

Clear cell eccrine carcinomas of the skin are rare and have been reported with several names. Of the 47 cases found in the literature, only one had the lesion in the sole. The present case is a 38 year old woman with an 18 year history of a 3.2 cm lesion in the lateral portion of the sole in the right foot. The patient developed inguinal metastases four and five months after the plantar resection, and suffered a local recurrence on two occasions. The histopathologic analysis of the sole lesion showed a neoplasm with more than 80% of clear cells, and less clear cells in the metastatic and recurrent lesions. Clear cells showed diffuse positivity to PAS with diastase lability. PAS reactivity was related to the presence of clear cells. Focal reactivity of mucin and colloidal iron in sebaceous-like cells and tubular structures was seen. Also, we found diffuse cytoplasmic and membrane surface positivity of epithelial membrane antigen in the clear cells, and focal in poroid and sebaceous cells and in tubular structures. The carcinoembryonic antigen showed a focal positivity in poroid and sebaceous cells and in tubular structures. We also identified focal positivity of S-100 protein in the sebaceous-like cells. Cytophotometric measurement of the nuclear DNA showed euploid cells in the primary and metastatic lesions. We conclude that clear cell eccrine carcinomas comprise a heterogeneous group of lesions with variable biological behavior, but with morphological, histochemical and immunohistochemical markers useful in their diagnosis.