David Kim

Bio: David Kim is an academic researcher from LSU Health Sciences Center Shreveport. The author has contributed to research in topics: Cancer & Organ transplantation. The author has an hindex of 3, co-authored 5 publications receiving 23 citations.

Porcine Urinary Bladder Extracellular Matrix for the Salvage of Fibula Free Flap Skin Paddle: Technical Note and Description of a Case:

Abstract: This report establishes a novel application of a commercially available porcine urinary bladder extracellular matrix, MatriStem (ACell, Inc., Columbia, MD), in the salvage of partial loss of the skin paddle of a fibula osteoseptocutaneous free flap that was utilized for mandibular reconstruction.

Management of solid tumours in organ-transplant recipients.

Abstract: Malignancy is a well-recognised complication of transplantation and can occur de novo, as a recurrence of a pre-existing malignancy, or from transmission of malignancy from the donor. Common de-novo malignancies are those of the skin and the lymphoreticular system. Various solid-organ cancers have also been reported in transplant recipients and each poses a unique management challenge in view of the unusual setting. We review solid-organ cancers in transplant recipients and their management, including surveillance and prevention.

Local ablative treatments of oligometastases from head and neck carcinomas.

Abstract: Background Median survival for recurrent/metastatic (unknown poly/oligometastatic status) head and neck cancer patients (HNSCC) is ten months with best systemic treatment. Metastatic ablation shows promising results in selected patients with several tumor types. We aimed to assess the role of surgery and stereotactic ablative body radiotherapy (SABR) with respect to survival in HNSCC. Materials and methods Published data on metastatic HNSCC treated ablatively were analyzed. Results Five-year survival rates after pulmonary/liver metastasectomy exceed 20% in selected patients. Two-year survival after lung SABRT of metastasectomy yields 35%. Interesting data on survival and tolerance are reported in other metastatic sites. Conclusion Surgery yields the best level of evidence. However, non-invasive SABR is efficient and well-tolerated in lung/liver, bone and other metastatic locations. Systemic treatment may be given sequentially with ablative treatments, or omitted in well-identified situations. Proper patient selection for local ablative treatment and optimal therapeutic sequence should be assessed in randomized trials.

P2Y6 Receptor-Mediated Microglial Phagocytosis in Radiation-Induced Brain Injury.

Abstract: Microglia are the resident immune cells and the professional phagocytic cells of the CNS, showing a multitude of cellular responses after activation. However, how microglial phagocytosis changes and whether it is involved in radiation-induced brain injury remain unknown. In the current study, we found that microglia were activated and microglial phagocytosis was increased by radiation exposure both in cultured microglia in vitro and in mice in vivo. Radiation increased the protein expression of the purinergic receptor P2Y6 receptor (P2Y6R) located on microglia. The selective P2Y6 receptor antagonist MRS2578 suppressed microglial phagocytosis after radiation exposure. Inhibition of microglial phagocytosis increased inhibitory factor Nogo-A and exacerbated radiation-induced neuronal apoptosis and demyelination. We also found that the levels of protein expression for phosphorylated Ras-related C3 botulinum toxin substrate 1 (Rac1) and myosin light chain kinase (MLCK) were elevated, indicating that radiation exposure activated Rac1 and MLCK. The Rac1 inhibitor NSC23766 suppressed expression of MLCK, indicating that the Rac1-MLCK pathway was involved in microglial phagocytosis. Taken together, these findings suggest that the P2Y6 receptor plays a critical role in mediating microglial phagocytosis in radiation-induced brain injury, which might be a potential strategy for therapeutic intervention to alleviate radiation-induced brain injury.

Approach to oligometastatic disease in head and neck cancer, on behalf of the GORTEC.

Abstract: Median survival for recurrent/metastatic head and neck squamous cell cancer (HNSCC) patients is about 10 months after first-line best systemic treatment. We aimed to assess current approaches of oligometastatic HNSCC patients by the analysis of current concept and published data (1995-2017) in this population. Five-year survival rates are over 20% in selected patients who undergo metastasis-directed therapy by either surgery or stereotactic irradiation. Human papillomavirus(+) HNSCC patients have more disseminated metastases but respond more favorably and also benefit from ablative treatments. Treatments of oligometastases are expanding rapidly. Unmet needs include revised imaging follow-up strategies to detect metastases earlier, identification of predictive noninvasive biomarkers for treatment guidance, assessment and corrections of biases in current studies and randomized clinical trials.