Neurosarcomatous amelanotic transformation of malignant melanoma presenting as malignant periopheral nerve sheath tumor: Rare case report.

RATIONALE: Malignant melanoma (MM) is notorious for its remarkable morphological variation and aberrant histopathological patterns. In addition, Malignant Periopheral Nerve Sheath Tumor (MPNST) is an uncommon but aggressive soft tissue sarcoma. Because of the common embryological origin of melanocytes and Schwann cells in the neural crest, discriminating between a particular type of MM and MPNST can be difficult, particularly when they are amelanotic. Our goal is to increase awareness among clinicians of the rare variations of MM and the importance of medical history in improving the accuracy of the final clinical diagnosis. PATIENT CONCERNS: A 68-year-old man was admitted to the hospital due to pain in his right ankle, which had persisted for 8 months, along with swelling for 4 months. Medical history revealed delayed healing of right plantar for 5 years after a traumatic injury. DIAGNOSES: The ankle mass was initially diagnosed as MPNST through biopsy. After reviewing the patient's medical history and receiving the final pathological report following amputation, we have revised the diagnosis to metastatic amelanotic desmoplastic melanoma in the ankle part and lentigo maligna melanoma in the plantar part. This is due to both lesions displaying positive markers or mutated genes in immunohistology and Gene Mutation Detection, indicating homology between the 2 tumors. INTERVENTIONS: Due to the malignant characteristics of the tumor and the patient's wishes, amputation of the right lower leg was carried out. OUTCOMES: Subsequently, the patient was treated with interferon-γ and immunosuppressant PD-1 inhibitor, and survived for 1 year after amputation. LESSONS: Clinical data, immunohistochemisty biomarkers and genes detection results can serve as valuable evidence for pathologists and clinicians in identifying the disease process. Collaborative efforts between clinicians and scientists are crucial in order to identify specific markers that can effectively differentiate between the 2 tumors, thereby enhancing the conclusiveness of the diagnosis.

Effects of different processing parameters of mobile DR on image quality of bedside chest radiography / 中国医学影像技术

Objective To explore the effects of different processing parameters of mobile digital radiography (DR) on image quality of bedside chest radiography.Methods Post processing parameter on 150 cases bedside DR chest image like multi frequency laplasse transform (MLT),image processing (IP) were modified,and the optimization scheme of post-processing parameters were analyzed and summarized.The paired sample t test was used to compare the difference of the imaging quality score and optical density between the default parameter group and the post processing parameter optimization group through measure the optical density of lung related area.Results Brightness,contrast and the low density in dynamic range were the main factors affecting the quality of bedside chest radiography.After modifying and optimizing the post-processing parameters,the density value of the second intercostal area was 1.68±0.04,the density value of the hilum was 0.77±0.46,the density value of pulmonary peripheral (near chest wall 1 cm and overlap with a single rib) was 0.62± 0.06,the density value of cardiac shadow was 0.44 ± 0.04,the density value of subphrenic was 0.37 ± 0.04,the lung markings was clearly showed in the lateral field of lung and was visible in the spine and heart shadow area which meet the diagnostic requirement.The density value of those parts before modify were lower than the modify value which was more closer to the reference density value,and the difference had statistically significant.The image quality score of the postprocessing parameter optimization group was 3.53 ± 0.14,which was higher than 3.02 ± 0.23 of the default parameter group,and the difference had statistically significant.Conclusion The appropriate post-processing parameters is the key to guarantee the reasonable density of lung areas image quality and the optimization post-processing parameter can improve the image quality of bedside chest radiography by the mobile DR.