Pulmonary lymphangioleiomyomatosis: a case report with immunohistochemical details and DNA analysis

The Epidemiology and Clinical Features of Lymphangioleiomyomatosis (LAM): A Descriptive Study of 33 Case Reports

Lymphangioleiomyomatosis (LAM) is a rare, slow-growing metastasizing neoplasm in which smooth muscle-like cells infiltrate the lung parenchyma and cause cystic lung damage. The common early symptoms include shortness of breath, pneumothorax, and chest pain. Lymphangioleiomyomatosis mainly involves the lungs, kidneys, and lymph nodes. This study reviews the characteristics of lymphangioleiomyomatosis to identify any possible changes in the prevalence of symptoms of the disease. We conducted a literature review of case reports on lymphangioleiomyomatosis from PubMed and Google Scholar. Variables of interest were age, gender, symptoms, vitals, immunostaining, and radiological findings. Data were transferred to an Excel spreadsheet (Microsoft Corporation, Redmond, WA), and mean, median, standard deviation, frequencies, and proportions were calculated using R version 1.1.456 (RStudio: Integrated Development for R. RStudio, PBC, Boston, MA). Lymphangioleiomyomatosis is a rare case and so not much of the literature could be found online. Thirty-three case reports were included in this study, and females accounted for 78.78% of the presentations. The average age was 38 years, SD 14.41 years. Shortness of breath was the most frequent symptom (60.6%), followed by pneumothorax (57.57%), chest pain (42.42%), cough (24.24%), and pleural effusion (1.25%).

Therapeutic Strategies for Treatment of Pulmonary Lymphangioleiomyomatosis (LAM)

INTRODUCTION

Pulmonary lymphangioleiomyomatosis (LAM) is a rare progressive lung disease affecting almost exclusively women. Neoplastic growth of atypical smooth muscle-like cells in the lung induces destruction of lung parenchyma leading to the formation of lung cysts, rupture of which results in spontaneous pneumothorax. LAM occurs sporadically or in association with inherited hamartoma syndrome tuberous sclerosis complex (TSC). Progression of LAM often results in loss of pulmonary function and death. Increasing understanding of neoplastic LAM cell growth is driving the development of therapeutic approaches targeting the disease progression.

AREAS COVERED

This review provides background to understand the rationale for current treatments used in patients with LAM, to critically appraise the evidence for these treatments, and to discuss future treatment approaches. The literature review includes publications from PubMed and clinicaltrials.gov/.

EXPERT OPINION

Targeting mTOR activation with rapamycin analogs sirolimus and everolimus are awaiting approval by the FDA for treatment of LAM. A number of other treatment options have been investigated and are currently tested in clinical trials to target LAM cell survival and metastasis. Key remaining and poorly understood areas for development and validation of therapeutic targeting in LAM are destruction of lungs, pathological lymphangiogenesis, and hormonal regulation. Future will reveal whether they could be targeted therapeutically.

In pulmonary lymphangioleiomyomatosis expression of progesterone receptor is frequently higher than that of estrogen receptor

Lymphangioleiomyomatosis (LAM) of the lung is a rare low-grade malignancy affecting primarily women of childbearing age. LAM is characterized by the proliferation of SMA and HMB-45 positive spindle-shaped and epithelioid cells throughout the lung in the form of discrete lesions causing cystic destruction and ultimately respiratory insufficiency. LAM occurs sporadically or in patients with tuberous sclerosis complex (TSC) and is etiologically linked to mutations in the TSC1 and TSC2 genes. Although LAM cells are known to express estrogen and progesterone receptors (ER and PR, respectively), their respective expression level was never determined. Therefore, here we measured the immunohistochemical expression of ERs and PRs in a large series of pulmonary LAM cases using the Aperio Spectrum Analysis Platform. Our case series comprised open lung biopsy specimens from 20 LAM patients and lungs explanted during the course of lung transplant from 24 patients. All cases were positive for ER and PR. PR expression was statistically significantly higher than ER in 80 % of the biopsies while ER predominated only in one case. Specimens from explanted cases of LAM had relatively fewer PR-positive nuclei. As a result, PR expression was significantly higher than ER in 38 % of the cases, whereas ER predominated in 33 %. Overall, PR expression predominated in 57 % of cases and ER in 21 %. These data indicate that PR frequently prevails over ER in pulmonary LAM. LAM is unusual in its high PR/ER ratio; other female neoplasms show a definite prevalence of ER. Our findings therefore warrant further study of PR function in LAM.

Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare idiopathic disease predominately affecting women. The disease is characterized by peribronchial, perivascular, and perilymphatic proliferation of smooth muscle like cells resulting in vascular and airway obstruction and cyst formation. The natural history of pulmonary LAM is unknown, and it displays remarkable diversity in its clinical course. More than 400 citations are currently listed in the literature for LAM. This article reviews and updates the rapidly expanding knowledge about LAM.