Application of Delayed Surgical Managements in Patients with Stensen's Duct Injury.

The study aimed to retrospectively evaluate surgical treatment outcomes after delayed parotid gland and duct injuries. Nine patients subjected to parotid gland and duct injuries with 1- to 3-month treatment delay were retrospectively evaluated with special reference of etiology, past medical history, and injury location. Conservative treatment, microsurgical anastomosis, and diversion of salivary flow or ligation were chosen for delayed parotid gland and duct injuries concerning to their site of injury, time of repair and procedures. Assistant treatment as pressure dressing was adopted thereafter. All patients experienced an uneventful recovery at the time of finalizing the study. Two patients received Stensen's duct ligation, 5 received microsurgical anastomosis and 2 accepted salivary flow diversion for 5 patients with sialoceles and 4 patients with fistulas, and no re-occurrence was found. Facial paralysis occurred after surgery in 4 patients, and 3 of them recovered after the nerve nutrition treatment. Our study suggested that appropriate surgical treatment is efficient for the re-establishment of the tissue function and facial aesthetic for delayed injury of the parotid and its duct.

Communication between lymphatic and venous systems in mice.

The lymphatic system in mice consists of lymphatic vessels and 22 types of lymph nodes. Metastatic tumor cells in the lymphatic system spread to distant organs through the venous system. However, the communication routes between the lymphatic and venous systems have not been fully elucidated. Here, we identify the communication routes between the lymphatic and venous systems in the axillary and subiliac regions of MXH10/Mo-lpr/lpr inbred mice, which develop systemic swelling of lymph nodes up to 10mm in diameter, allowing investigation of the topography of the lymph nodes and lymphatic vessels. Using a gross anatomy dissection approach, the efferent lymphatic vessels of the proper axillary lymph node were shown to communicate with the subclavian vein. Furthermore, we found that the thoracoepigastric vein, which connects the subclavian vein and inferior vena cava, runs adjacent to the subiliac and proper axillary lymph nodes, and receives venous blood from these lymph nodes routed through small branches. The direction of blood flow in the thoracoepigastric vein occurred in two directions in the intermediate region between the proper axillary lymph node and subiliac lymph node; one to the subclavian vein, the other to the inferior vena cava. This paper reveals the anatomy of the communication between the lymphatic and venous systems in the axillary and subiliac regions of the mouse, and provides new insights relevant to the investigation of the mechanisms of lymph node metastasis and cancer immunology, and the development of diagnostic and treatment methods for lymph node metastasis, including drug delivery systems.

Activation of latent metastases in the lung after resection of a metastatic lymph node in a lymph node metastasis mouse model.

Iatrogenic induction of regional and distant cancer metastases is a risk associated with clinical resection of tumor-positive sentinel lymph nodes. However, there have been no studies of this risk in a mouse model of cancer metastasis. Here, we report that resection of a tumor-bearing subiliac lymph node (SiLN) enhanced lung metastasis in a mouse model of lymph node metastasis. Bioluminescence imaging revealed that metastatic tumor cells in the secondary lymph node continued to grow after resection of the SiLN, and that the probability of metastasis to the lungs was increased when the interval between SiLN inoculation and resection was reduced. Futhermore, histological analysis demonstrated that latents in the lung were stimulated to grow after resection of the SiLN. Fluorescence imaging indicated that the route of tumor cell dissemination from SiLN to the lung was the venous system located over the SiLN. We speculate that our mouse model will be useful for studying the mechanisms of tumor cell latency, with a view to improving the detection and treatment of latent metastases.

Lymphatic mapping of mice with systemic lymphoproliferative disorder: usefulness as an inter-lymph node metastasis model of cancer.

Preclinical models of lymph node (LN) metastasis are fundamental to the study and design of new techniques for the diagnosis and treatment of LN metastasis. However, the identification of LNs and lymphatic vessels (LVs) in mice is challenging with conventional imaging modalities, since the LN diameter in normal mice is 1-2 mm. Here, we describe MXH10/Mo-lpr/lpr (MXH10/Mo/lpr) inbred mice, which develop systemic swelling of LNs up to 10 mm in diameter, allowing investigation of the topography of LNs and LVs. Using a gross anatomy dissection approach, we identified 22 different LNs situated in the head and neck, limbs, thoracic and abdominal regions. Furthermore, four peripheral inter-LN vessels were found: from the subiliac LN (SiLN) to the proper axillary LN (PALN); from the parotid LN to the caudal deep cervical LN; and from the popliteal LN to both the sciatic LN and the SiLN. Metastasis to the PALN via LVs was induced by inoculating FM3A/Luc mouse mammary carcinoma cells into the SiLN. Our results demonstrate that the MXH10/Mo/lpr mouse strain is an excellent model in which to investigate lymphatic drainage and inter-LN metastasis of cancer. This paper unveils the anatomy of murine lymphatics to give new insights into the investigation of inter-LN metastasis of cancer, especially the mechanisms involved in the trafficking of cancer cells through inter-LN vessels. The results provide data that may prove very useful in the quest to develop better lymph drainage-based drug delivery systems.