Tratamiento de la linfangioleiomiomatosis con sirolimus

Official American Thoracic Society/Japanese Respiratory Society Clinical Practice Guidelines: Lymphangioleiomyomatosis Diagnosis and Management

BACKGROUND

Lymphangioleiomyomatosis (LAM) is a rare cystic lung disease that primarily affects women. The purpose of these guidelines is to provide recommendations for the diagnosis and treatment of LAM.

METHODS

Systematic reviews were performed to summarize evidence pertinent to our questions. The evidence was summarized and discussed by a multidisciplinary panel. Evidence-based recommendations were then formulated, written, and graded using the Grading of Recommendations, Assessment, Development, and Evaluation approach.

RESULTS

After considering the panel's confidence in the estimated effects, the balance of desirable (i.e., benefits) and undesirable (i.e., harms and burdens) consequences of treatment, patient values and preferences, cost, and feasibility, recommendations were formulated for or against specific interventions. These included recommendations for sirolimus treatment and vascular endothelial growth factor D testing and recommendations against doxycycline and hormonal therapy.

CONCLUSIONS

Evidence-based recommendations for the diagnosis and treatment of patients with LAM are provided. Frequent reassessment and updating will be needed.

Intracrine steroid production and mammalian target of rapamycin pathways in pulmonary lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare, potentially fatal disease primarily affecting young women. Estrogens enhance cell proliferation and progression of the tumor. Clinical trials using molecularly targeted agents such as endocrine manipulation and mammalian target of rapamycin (mTOR) inhibitors are in progress, but the status of these molecules, including aromatase and mTOR, has not been explored in LAM tissue. We first examined immunoreactivity for sex steroid receptors (estrogen receptor [ER] α, ERβ, progesterone receptor, androgen receptor), sex steroid-synthesizing enzymes (aromatase, steroid sulfatase, 17β-hydroxysteroid dehydrogenase 1, 5α-reductases), apoptotic suppression factor (Bcl-2), and factors involved in the mTOR signaling pathway in 30 pulmonary LAM tissues. Immunoreactivity for ERα, ERβ, progesterone receptor, aromatase, and Bcl-2 was significantly more abundant in epithelioid cells, whereas the status of androgen receptor, 5α-reductases, and phospho-mTOR signaling was not different in epithelioid and spindle-shaped LAM cells. We further examined the correlation among H scores of these markers using hierarchical clustering analysis. The results indicated that LAM tumors can be further classified into "aromatase" and "mTOR" groups on the basis of the patterns of immunoreactivity, and the 2 types could benefit from different modes of therapy.

The neural crest lineage as a driver of disease heterogeneity in Tuberous Sclerosis Complex and Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare neoplastic disease, best characterized by the formation of proliferative nodules that express smooth muscle and melanocytic antigens within the lung parenchyma, leading to progressive destruction of lung tissue and function. The pathological basis of LAM is associated with Tuberous Sclerosis Complex (TSC), a multi-system disorder marked by low-grade tumors in the brain, kidneys, heart, eyes, lung and skin, arising from inherited or spontaneous germ-line mutations in either of the TSC1 or TSC2 genes. LAM can develop either in a patient with TSC (TSC-LAM) or spontaneously (S-LAM), and it is clear that the majority of LAM lesions of both forms are characterized by an inactivating mutation in either TSC1 or TSC2, as in TSC. Despite this genetic commonality, there is considerable heterogeneity in the tumor spectrum of TSC and LAM patients, the basis for which is currently unknown. There is extensive clinical evidence to suggest that the cell of origin for LAM, as well as many of the TSC-associated tumors, is a neural crest cell, a highly migratory cell type with extensive multi-lineage potential. Here we explore the hypothesis that the types of tumors that develop and the tissues that are affected in TSC and LAM are dictated by the developmental timing of TSC gene mutations, which determines the identities of the affected cell types and the size of downstream populations that acquire a mutation. We further discuss the evidence to support a neural crest origin for LAM and TSC tumors, and propose approaches for generating humanized models of TSC and LAM that will allow cell of origin theories to be experimentally tested. Identifying the cell of origin and developing appropriate humanized models is necessary to truly understand LAM and TSC pathology and to establish effective and long-lasting therapeutic approaches for these patients.

Genetics of rare mesenchymal tumors: implications for targeted treatment in DFSP, ASPS, CCS, GCTB and PEComa

Soft tissue and bone sarcomas comprise a heterogeneous group of mesenchymal tumors that include roughly 130 distinct diagnostic entities. Many of them are exceptionally rare, with only few cases diagnosed worldwide each year. Development of novel targeted treatment in this group of tumors is of special importance since many sarcoma subtypes are resistant to conventional chemotherapy and the effective therapeutic options are limited. In this review we aim to discuss the molecular implications for targeted therapy in selected rare soft tissue and bone sarcoma subtypes, including dermatofibrosarcoma protuberans (DFSP), alveolar soft part sarcoma (ASPS), clear cell sarcoma (CCS), giant cell tumor of bone (GCTB) and perivascular epithelioid cell neoplasms (PEComas). This article is part of a Directed Issue entitled: Rare cancers.

Topical rapamycin (sirolimus) for facial angiofibromas

Rapamycin (sirolimus) is a fungal fermentation product that inhibits the proper functioning of a serine/threonine protein kinase in mammalian cells eponymously named mammalian target of rapamycin, or mTOR. Rapamycin is a novel class of anticancer and immunosuppressant drugs targeting the proteins at molecular level. Rapamycin (sirolimus) is routinely incorporated in drug-eluting stents used for cardiac angioplasty. In recent years, rapamycin was found to be efficacious in managing the symptom complex of tuberous sclerosis, i.e. renal angiomyolipoma, giant cell astrocytoma and pulmonary lymphangiomyomatosis. Various investigators have also proved that topically applied rapamycin causes regression of facial angiofibromas, giving better cosmetic results.

Lymphangioleiomyomatosis: current and future

Lymphangioleiomyomatosis is a rare slowly progressive lung disease that affects almost exclusively young women of reproductive age. It occurs sporadically or in association with Tuberous Sclerosis Complex. LAM is characterized by cystic remodeling of the lung parenchyma, due to proliferation of abnormal smooth muscle-like LAM cells and presence of extra pulmonary manifestations such as lymphadenopathy, angiomyolipomas and abdominal lymphangioleiomyomas. The most common clinical manifestations are progressive dyspnea on exertion, pneumothorax and chylous effusions. Currently there is no curative treatment for the disease, but the ongoing study of the genetic and molecular pathways implicated in the pathogenesis of the disease could lead to targeted therapy.

Optimizing treatments for lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM), a multisystem disease predominantly affecting premenopausal women, is associated with cystic lung destruction and lymphatic and kidney tumors. LAM results from the proliferation of a neoplastic cell that has mutations in the tuberous sclerosis complex 1 or 2 genes, leading to activation of a critical regulatory protein, mammalian target of rapamycin. In this report, we discuss the molecular mechanisms regulating LAM cell growth and report the results of therapeutic trials employing new targeted agents. At present, inhibitors of mammalian target of rapamycin such as sirolimus appear to be the most promising therapeutic agents, although drug toxicity and development of resistance are potential problems. As the pathogenesis of LAM is being further recognized, other therapeutic agents such as matrix metalloproteinase inhibitors, statins, interferon, VEGF inhibitors, chloroquine analogs and cyclin-dependent kinase inhibitors, along with sirolimus or a combination of several of these agents, may offer the best hope for effective therapy.