A cartilage-forming tumor of the mandibular angle: a case report.

BACKGROUND: Mandible can be the site of benign or malignant lesions of different origins, including odontogenic and non-odontogenic lesions. Cartilage-forming tumors have been rarely reported at this site. Chondrosarcoma is a rare malignant cartilage-producing neoplasm that is extremely rare in the mandible. The rarity of cartilage-forming tumor occurrence in the mandible can make diagnosis difficult for pathologists, as they do not expect this type of tumor at this anatomical site. Here we report a case of chondrosarcoma of mandibular angle. CASE PRESENTATION: A 70-year-old Moroccan male patient consulted a dentist for wisdom tooth pain. Wisdom tooth extraction was conducted. After 6 months, the patient reported the recurrence of pain associated with swelling in the mandibular area and paresthesia along the path of the mandibular nerve. A panoramic radiograph demonstrated a mixed radiolucent-opaque lesion involving the mandibular angle. Computed tomography showed a large osteolytic spontaneously hypointense and multilobulated lesion. A biopsy was done. Histopathological examination revealed sheets and irregular lobules of atypical cells presenting cartilaginous differentiation. Tumor cells showed severe nuclear atypia and were located within a hyaline cartilage matrix. Some foci of necrosis were noted. Osteoid deposits were not found. The patient was diagnosed with grade III chondrosarcoma and underwent a right segmental mandibulectomy with submandibular lymph node dissection. Macroscopically, the tumor was localized in the mandibular angle with extension in the mandibular body. Histopathology confirmed the previous diagnosis of grade III chondrosarcoma and did not show any lymph node metastasis. CONCLUSIONS: Owing to many histological similarities, grade III chondrosarcoma must be distinguished from chondroblastic osteosarcoma and metastatic lesions. In addition, chondroblastic osteosarcoma of the jawbones has a worse prognosis than chondrosarcoma, making the distinction between these two malignant tumors the most important concern of the pathologist when dealing with a cartilage-forming tumor at this site. Surgery with wide excision margins remains the best therapeutic approach, while the role of radiotherapy is controversial. The management of mandibular chondrosarcoma requires a multidisciplinary approach involving maxillofacial surgeons, radiologists, pathologists, and oncologists.

What Open-Lung Biopsy Teaches Us about ARDS in COVID-19 Patients: Mechanisms, Pathology, and Therapeutic Implications.

Difficulties have risen while managing Acute Respiratory Distress Syndrome (ARDS) caused by COVID-19, although it meets the Berlin definition. Severe hypoxemia with near-normal compliance was noted along with coagulopathy. Understanding the precise pathophysiology of this atypical ARDS will assist researchers and physicians in improving their therapeutic approach. Previous work is limited to postmortem studies, while our report addresses patients under protective lung mechanical ventilation. An open-lung minithoracotomy was performed in 3 patients who developed ARDS related to COVID-19 and were admitted to the intensive care unit to carry out a pathological and microbiological analysis on lung tissue biopsy. Diffused alveolar damage with hyaline membranes was found, as well as plurifocal fibrin microthrombi and vascular congestion in all patients' specimens. Microbiological cultures were negative, whereas qualitative Reversed Transcriptase Polymerase Chain Reaction (RT-PCR) detected SARS-CoV-2 in the pulmonary parenchyma and pleural fluid in two patients. COVID-19 causes progressive ARDS with onset of severe hypoxemia, underlying a dual mechanism: shunt effect through diffused alveolar damage and dead space effect through thrombotic injuries in microvascular beds. It seems reasonable to manage this ventilation-perfusion ratio mismatch using a high dose of anticoagulant combined with glucocorticoids.

[Brain tumors in children: about 136 cases]. / Tumeurs cérébrales de l'enfant: à propos de 136 cas.

Brain tumors are the most diagnosed solid tumors in children under the age of 15 years worldwide. However, the epidemiological and anatomopathological profile of these tumors has been poorly described in African and, particularly, in Moroccan literature. This study highlights the epidemiological and anatomopathological peculiarities of primary brain tumors in children living in the region of Marrakech (south Morocco). We conducted a retrospective study in the Division of Anatomic Pathology at the Mohammed VI University Hospital, Marrakech from 2004 to 2016. One hundred and thirty-six patients were diagnosed with primary brain tumor, a mean of 11.33 cases per year. The average age of patients was 8.28 years. Sex-ratio (M/F) was 1.6 with a slight male predominance. Infratentorial tumors were found in 61,53% of cases while supratentorial tumors were found in 38.47% of cases. Infratentorial tumors mainly occurred in the cerebellar hemisphere (61.4%). Eighteen histological types were diagnosed. Astrocytoma and medulloblastoma accounted for 46,32% (29.41% and 16.91%, respectively). In our context, the majority of brain tumors in children was predominant in both age groups: 5-9 years and 10-15 years. The epidemiological data of these tumors from south Morocco are mostly consistent with those already published in North Country's literature and in other non-african countries' literature.

Posterior cerebral fossa medulloepithelioma: report of a case.

BACKGROUND: Medulloepithelioma is a rare primitive neuroectodermal tumor of the central nervous system, usually developing in childhood. Due to its rarity, the optimal management is still unknown. The prognosis is poor, especially when resection is incomplete. Adjuvant radiochemotherapy is often indicated. CASE PRESENTATION: We report a rare case of infratentorial medulloepithelioma in a 3 year old girl. She presented symptoms of increased intracranial pressure. On examination, she had coordination problems, ptosis and exotropia of the right eye. Magnetic resonance imaging demonstrated a large cerebellar vermix tumor. Immuno-histochemistry revealed a diffuse positivity for Vimentin and focal positivity for the epithelial membrane antigen, but Glial Fibrillary Acidic Protein and Synaptophysin were negative, the MIB-1 antibody was very high. She received postoperative craniospinal irradiation and died 7 months later. CONCLUSION: We describe the features (epidemiological, clinical, histological, immunohistochemical and therapeutic outcomes) of our case and confront it to literature data.