Lymphoscintigraphy for the assessment of autologous stem cell implantation in chronic lymphedema

The relationship between the drainage function of inguinal lymph nodes and unilateral pelvic cancer-related lymphedema: A retrospective analysis

The aim of this study was to investigate the relationship between iliolumbar lymph nodes (LNs), inguinal LNs, and unilateral pelvic cancer-related lymphedema by retrospective analysis of lymphoscintigraphy data.Ninety-six patients (3 men and 93 women; mean age, 53.3 ± 11.3 years) with pelvic cancer-related lymphedema were enrolled in this retrospective study. Lymphoscintigraphy was performed at 1 hour and 4 to 6 hours after injection. The visualization of inguinal LNs and iliolumbar LNs were recorded.According to statistical analysis, the display of inguinal LNs in lymphoscintigraphy has a significant negative correlation with ipsilateral lower limb lymphedema (P < .01, r = -0.561). However, there is no correlation between the show of iliolumbar LNs and ipsilateral lower extremity lymphedema (P = .056, r = -0.138). When lymphoscintigraphy was performed at 1 hour after injection, there were 13 out of 96 patients without inguinal LNs revealed on imaging, but at 4 to 6 hours after injection, inguinal LNs were seen in lymphoscintigraphy.The drainage function of inguinal LNs has a significant negative correlation with ipsilateral pelvic cancer-related lymphedema. Treatment dedicated to restoring the drainage function of LNs in the inguinal region may effectively relieve lymphedema. The image acquisition at 4 to 6 hours after injection is necessary for significant additional information.

Therapeutic Potential of Mesenchymal Stem Cells for Postmastectomy Lymphedema: A Literature Review

Upper limb lymphedema is one of the most common complications after breast cancer surgery and radiotherapy. Despite various physical therapy and surgical options available, the impaired lymph fluid drainage may be progressive due to lymphatic vascular insufficiency making treatment more difficulty. Stem cell therapy provides a promising alternative in the treatment of various chronic diseases. The wide applicability of cell therapy has been reviewed throughout literature. This review provides an overview of recent progress in the therapeutic effect of adult stem cells for primary and secondary lymphedema after breast surgery in preclinical studies and clinical cases. We start with a brief introduction about the pathophysiological mechanisms of postmastectomy lymphedema. Regarding existing treatments, we systematically summarize the benefits and limitations of recent progress. Because of their multidirectional differentiation potential and growth factor secretion, stem cell therapy shows promising results in the management of light to severe lymphedema. Increasing evidences have demonstrated a noticeable reduction in postmastectomy lymphedema and increased lymph-angiogenesis after specific stem cell therapy. Current data suggests that stem cell therapy in lymphedema treatment provides reversal of pathological reorganization associated with lymphedema progression. Finally, we propose potential strategies for overcoming the challenges in the development of multipotent progenitor cells for the treatment and prevention of lymphedema in clinical practice.

Adipose-derived stem cell therapy shows promising results for secondary lymphedema

Lymphedema is mainly identified by progressive soft tissue swelling in impaired lymphatic system. Secondary lymphedema attributed to cancer therapy, parasite infection, and trauma remains a serious global disease. Patients with lymphedema suffer swelling, pain, and fatigue, with the dysfunction of the deformed extremities reducing the quality of life and increasing the risk of infection and lymphangiosarcoma. Adipose-derived stem cells (ADSCs) possess prominent regenerative potential to differentiate into multilineage cells, and produce various lymphangiogenic factors, making ADSC therapy a promising approach for lymphedema. The development of lymphedema consists of local inflammation, the fibrosis of lymphatic vessels, and the deposition of adipose fat. Existing animal models do not mimic the chronic inflammation environment, therefore suitable models are required in further studies. Some signal pathways and molecular mechanisms in physiological and pathological lymphagiogenesis remain unclear. In previous animal and human trials, ADSC therapy reduced edema in varying degrees. A larger number of trials with larger samples and longer follow-up periods are required to verify the efficiency and feasibility of ADSC therapy. ADSCs are of easy availability and immune exemption, making them a candidate for lymphedema treatment. Whether ADSCs enhance malignant characteristics or trigger the malignant change deserves further exploration and study before ADSC therapy can be made widely available.

Adipose-Derived Stem Cells Promote Intussusceptive Lymphangiogenesis by Restricting Dermal Fibrosis in Irradiated Tissue of Mice

Currently, there is no definitive treatment for lymphatic disorders. Adipose-derived stem cells (ADSCs) have been reported to promote lymphatic regeneration in lymphedema models, but the mechanisms underlying the therapeutic effects remain unclear. Here, we tested the therapeutic effects of ADSC transplantation on lymphedema using a secondary lymphedema mouse model. The model was established in C57BL/6J mice by x-irradiation and surgical removal of the lymphatic system in situ. The number of lymphatic vessels with anti-lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) immunoreactivity increased significantly in mice subjected to transplantation of 7.5 × 10⁵ ADSCs. X-irradiation suppressed lymphatic vessel dilation, which ADSC transplantation could mitigate. Proliferative cell nuclear antigen staining showed increased lymphatic endothelial cell (LEC) and extracellular matrix proliferation. Picrosirius red staining revealed normal collagen fiber orientation in the dermal tissue after ADSC transplantation. These therapeutic effects were not related to vascular endothelial growth factor (VEGF)-C expression. Scanning electron microscopy revealed structures similar to the intraluminal pillar during intussusceptive angiogenesis on the inside of dilated lymphatic vessels. We predicted that intussusceptive lymphangiogenesis occurred in lymphedema. Our findings indicate that ADSC transplantation contributes to lymphedema reduction by promoting LEC proliferation, improving fibrosis and dilation capacity of lymphatic vessels, and increasing the number of lymphatic vessels via intussusceptive lymphangiogenesis.

Review of preclinical and clinical studies of using cell-based therapy for secondary lymphedema

Secondary lymphedema is associated with impaired lymph fluid drainage and remains incurable. Alternatively, cell-based therapy may pave the way for lymphedema treatment. We found 11 animal and seven human studies had been conducted from 2008 to 2018. Most studies showed great potential for this treatment modality. Emerging studies have focused on novel techniques, such as coupling cell therapy with lymph node transfer, or adding growth factors to cell therapy.

Adipose-derived regenerative cells and fat grafting for treating breast cancer-related lymphedema: Lymphoscintigraphic evaluation with 1 year of follow-up

BACKGROUND

Breast cancer-related lymphedema (BCRL) is a feared late complication. Treatment options are lacking at present. Recent studies have suggested that mesenchymal stromal cells can alleviate lymphedema. Herein, we report the results from the first human pilot study with adipose-derived regenerative cells (ADRCs) for treating BCRL with 1 year of follow-up.

MATERIAL AND METHODS

We included 10 patients with BCRL. ADRCs were injected directly into the axillary region together with a scar-releasing fat grafting procedure. Primary endpoint was change in arm volume. Secondary endpoints were change in patient-reported outcomes, changes in lymph flow, and safety.

RESULTS

During follow-up, no significant change in volume was noted. Patient-reported outcomes improved significantly with time. Five patients reduced their use of conservative management. Quantitative lymphoscintigraphy did not improve on the lymphedema-affected arms. ADRCs were well tolerated, and only minor transient adverse events related to liposuction were noted.

CONCLUSIONS

In this pilot study, a single injection of ADRCs improved lymphedema based on patient-reported outcome measures, and there were no serious adverse events during the follow-up period. Lymphoscintigraphic evaluation showed no improvement after ADRC treatment. There was no change in excess arm volume. Results of this trial need to be confirmed in randomized clinical trials.

Potential Applications of Using 68Ga-Evans Blue PET/CT in the Evaluation of Lymphatic Disorder: Preliminary Observations

PURPOSE

Potentials of 68Ga-NEB as a PET tracer in the evaluation of a variety of lymphatic drainage disorders were analyzed.

METHODS

68Ga-NEB was injected subcutaneously, and the PET/CT images were acquired in 13 patients with different suspected lymphatic drainage abnormality. The 68Ga-NEB PET/CT findings were compared with Tc-SC lymphoscintigraphy.

RESULTS

68Ga-NEB activity could be clearly observed in the lymphatic route on the PET/CT images from all the patients. In 5 (38.5%) of 13 patients tested, 68Ga-NEB PET/CT provided more information than the Tc-SC lymphoscintigraphy.

CONCLUSIONS

68Ga-NEB PET/CT can be used as an alternative of Tc-SC lymphoscintigraphy in the evaluation of lymphatic disorders, which enables fast results and might be more accurate than the conventional Tc-SC lymphoscintigraphy.