The changing face of a rare disease: lymphangioleiomyomatosis

Clinical, tomographic and functional comparison of sporadic and tuberous sclerosis complex-associated forms of lymphangioleiomyomatosis: a retrospective cohort study

Background

Lymphangioleiomyomatosis (LAM) is a rare disease that can occur sporadically (S-LAM) or associated with the tuberous sclerosis complex (TSC-LAM). The natural history of LAM is not completely understood, including whether there is a difference between the clinical courses of the two forms. This study aimed to compare the clinical, functional and tomographic features between S-LAM and TSC-LAM, and evaluate the annual rates of change in lung function.

Methods

This retrospective cohort study included patients with LAM followed up between 1994 and 2019. Clinical, functional and imaging variables were evaluated, and the lung cysts were automatically quantified. Quality of life and predictors of lung function impairment were accessed, and the annual rate of lung function decline was compared between S-LAM and TSC-LAM.

Results

Of the 107 patients included, 77 had S-LAM and 30 had TSC-LAM. Although patients with TSC-LAM had a higher prevalence of renal angiomyolipomas and neurological and dermatological manifestations, pulmonary function tests were similar. Patients with S-LAM had a greater rate of forced expiratory volume in 1 s decline and a higher extent of cysts. Pneumothorax, desaturation in the 6-minute walking test and a higher extent of lung cysts were predictors of functional impairment. A greater impact on vitality and emotional health was observed in the TSC-LAM.

Conclusion

Greater functional decline and a higher cystic extension were found in patients with S-LAM. Our study provides a broad clinical, functional and tomographic characterisation of patients with LAM, adding valuable information to the existing evidence to better understand the two forms of the disease.

A remote monitoring-enabled home exercise prescription for patients with interstitial lung disease at risk for exercise-induced desaturation

RATIONALE

Alternatives to center-based pulmonary rehabilitation are needed to improve patient access to this important therapy. A critical challenge to overcome is how to maximize safety of unsupervised exercise for at-risk patients. We investigated if a novel remote monitoring-enabled mobile health (mHealth) program is safe, feasible, and effective for patients who experience exercise-induced hemoglobin desaturation.

METHODS

An interstitial lung disease (ILD) commonly associated with pronounced exercise desaturation was investigated - the rare, female-predominant ILD lymphangioleiomyomatosis (LAM). Over a 12-week program, hemoglobin saturation (SpO2) was continuously recorded during all home exercise sessions. Intervention effects were assessed with 6-min walk test (6MWT), maximal cardiopulmonary exercise test (CPET), lower extremity computerized dynamometry, pulmonary function tests, and health-related quality of life (QoL) surveys. Safety was assessed by blood biomarkers of systemic inflammation and cardiac wall stress, and incidence of adverse events.

RESULTS

Fifteen LAM patients enrolled and 14 completed the intervention, with high adherence to aerobic (87 ± 15%) and strength (87 ± 12%) training components. An innovative characterization of exercise training SpO2 revealed that while mild-to-moderate desaturation was common during home workouts, participants were able to self-adjust exercise intensity and supplemental oxygen levels to maintain recommended exercise parameters. Significant improvements included 6MWT distance (+36 ± 34 m, p = 0.003), CPET time (p = 0.04), muscular endurance (p = 0.008), QoL (p = 0.009 to 0.03), and fatigue (p = 0.001 to 0.03). Patient acceptability and satisfaction indicators were high, blood biomarkers remained stable (p > 0.05), and no study-related adverse events occurred.

CONCLUSION

A remote monitoring-enabled home exercise program is a safe, feasible, and effective approach even for patients who experience exercise desaturation.

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%).

Pulmonary Langerhans cell histiocystosis (PLCH) and lymphangioleiomyomatosis (LAM) have circulating cells with loss of heterozygosity of the TSC2 gene

BACKGROUND

Lymphangioleiomyomatosis (LAM) and pulmonary Langerhans Cell Histiocytosis (PLCH) are cystic lung diseases in which a neoplastic cell is believed to be responsible for disease pathogenesis. The neoplastic LAM cell has mutations in the Tuberous Sclerosis Complex (TSC) genes, TSC1 or TSC2, whereas the neoplastic PLCH cell may have mutations in several genes, e.g., BRAF, NRAS, MAP2K1. These mutations are not specific for PLCH and they have been described in multiple cancers. TSC1 or TSC2 mutations and loss of heterozygosity (LOH) have also been described in cancers.

RESEARCH QUESTION

Is TSC2 LOH specific to LAM or is it also found in PLCH too?

STUDY DESIGN

We recruited LAM patients (53) and Healthy Volunteers (22) and compared the presence of cells with TSC2 LOH with PLCH patients (12). Blood and urine samples were collected for analysis.

METHODS

Fluorescence-activated cell sorting (FACS) was used to identify subpopulations of cells from blood and urine samples. We isolated CD45-CD235a-, CD45-CD235a+, CD45+CD235a- cells from blood following density gradient separation. Cells were screened for TSC2 LOH at 5 microsatellites markers (i.e., kg8, D16S3395, D16S3024, D16S521, D16S291). We obtained four cell subpopulations from urine (i.e., CD44v6+CD9+; CD44v6+CD9-; CD44v6-CD9+; CD44v6-CD9).

RESULTS

Using FACS, cells were isolated from blood and urine from PLCH patients that showed TSC2 LOH. Healthy volunteers did not have cells with TSC2 LOH. As a control, cells isolated from blood and urine from LAM patients gave results similar to those reported previously. These data show that TSC2 LOH is found in patients with cystic lung diseases with potential neoplastic characteristics, as well as in patients with cancer.

INTERPRETATION

The presence of TSC2 LOH in circulating cells is not specific for LAM. The data suggest that chromosomal abnormalities affecting the TSC2 gene are found in other diseases associated with cells having cancer-like neoplastic cells.

Evidence for shared genetic risk factors between lymphangioleiomyomatosis and pulmonary function

Introduction

Lymphangioleiomyomatosis (LAM) is a rare low-grade metastasising disease characterised by cystic lung destruction. The genetic basis of LAM remains incompletely determined, and the disease cell-of-origin is uncertain. We analysed the possibility of a shared genetic basis between LAM and cancer, and LAM and pulmonary function.

Methods

The results of genome-wide association studies of LAM, 17 cancer types and spirometry measures (forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio and peak expiratory flow (PEF)) were analysed for genetic correlations, shared genetic variants and causality. Genomic and transcriptomic data were examined, and immunodetection assays were performed to evaluate pleiotropic genes.

Results

There were no significant overall genetic correlations between LAM and cancer, but LAM correlated negatively with FVC and PEF, and a trend in the same direction was observed for FEV1. 22 shared genetic variants were uncovered between LAM and pulmonary function, while seven shared variants were identified between LAM and cancer. The LAM-pulmonary function shared genetics identified four pleiotropic genes previously recognised in LAM single-cell transcriptomes: ADAM12, BNC2, NR2F2 and SP5. We had previously associated NR2F2 variants with LAM, and we identified its functional partner NR3C1 as another pleotropic factor. NR3C1 expression was confirmed in LAM lung lesions. Another candidate pleiotropic factor, CNTN2, was found more abundant in plasma of LAM patients than that of healthy women.

Conclusions

This study suggests the existence of a common genetic aetiology between LAM and pulmonary function.

Improving Survival in Lymphangioleio-myomatosis: A 16-Year Observational Study in a Large Cohort of Patients

BACKGROUND

Over the last 2 decades, great progress has been made in the understanding of the clinical aspects and pathogenesis of lymphangioleiomyomatosis (LAM), leading to publication of guidelines and approval of an effective therapy.

OBJECTIVES

Aim of our study was to describe how the management and the natural history of this rare disease have changed after the publication of the ERS and American Thoracic Society/Japanese Respiratory Society guidelines and the introduction of sirolimus.

METHODS

We examined 162 LAM patients followed at our center between 2001 and 2017, reporting clinical characteristics and diagnostic approach. Response to sirolimus in patients undergoing long-term treatment and mortality risk, estimated in terms of cumulative incidence taking into account organ transplantation as a competing cause of the event, were evaluated. The difference in the cumulative incidence between the patients admitted to the observation before 2011 and after 2011, year of the publication of the MILES trial for the efficacy of sirolimus, has also been estimated.

RESULTS

Sixty-one patients had a histological diagnosis (22 from 2010 onward). 101 patients received a radiological diagnosis according to the guidelines criteria. Pulmonary function tests remained stable over a 3-year treatment period in patients who received sirolimus for over 12 months. The cumulative incidence of mortality after 10 years in the whole population was 25.5%. The cumulative incidence of mortality after 5 years was significantly lower in patients who entered the study since 2011 (after publication of the MILES trial) than in patients who entered the study before.

CONCLUSIONS

We provide the data supporting the long-term efficacy of sirolimus therapy in a large cohort of patients with functional impairment and other manifestations of the disease. Our results also suggest that the advent of sirolimus and the publication of international guidelines changed the natural history of the disease lowering the mortality and reducing the need of invasive diagnostic techniques.

Ultra-Small Lung Cysts Impair Diffusion Without Obstructing Air Flow in Lymphangioleiomyomatosis

Background

Lymphangioleiomyomatosis (LAM) is a rare lung disease found primarily in women of childbearing age, characterized by the formation of air-filled cysts, which may be associated with reductions in lung function. An experimental, regional ultra-high resolution CT scan identified an additional volume of cysts relative to standard chest CT imaging, which consisted primarily of ultra-small cysts.

Research Question

What is the impact of these ultra-small cysts on the pulmonary function of patients with LAM?

Study Design and Methods

A group of 103 patients with LAM received pulmonary function tests and a CT examination in the same visit. Cyst score, the percentage lung volume occupied by cysts, was measured by using commercial software approved by the US Food and Drug Administration. The association between cyst scores and pulmonary function tests of diffusing capacity of the lungs for carbon monoxide (Dlco) (% predicted), FEV₁ (% predicted), and FEV₁/FVC (% predicted) was assessed with statistical analysis adjusted for demographic variables. The distributions of average cyst size and ultra-small cyst fraction among the patients were evaluated.

Results

The additional cyst volume identified by the experimental, higher resolution scan consisted of cysts of 2.2 ± 0.8 mm diameter on average and are thus labeled the “ultra-small cyst fraction.” It accounted for 27.9 ± 19.0% of the total cyst volume among the patients. The resulting adjusted, whole-lung cyst scores better explained the variance of Dlco (P < .001 adjusted for multiple comparisons) but not FEV₁ and FEV₁/FVC (P = 1.00). The ultra-small cyst fraction contributed to the reduction in Dlco (P < .001) but not to FEV₁ and FEV₁/FVC (P = .760 and .575, respectively). The ultra-small cyst fraction and average cyst size were correlated with cyst burden, FEV₁, and FEV₁/FVC but less with Dlco.

Interpretation

The ultra-small cysts primarily contributed to the reduction in Dlco, with minimal effects on FEV₁ and FEV₁/FVC. Patients with lower cyst burden and better FEV₁ and FEV₁/FVC tended to have smaller average cyst size and higher ultra-small cyst fraction.

Clinical Trial Registration

ClinicalTrials.gov; No.: NCT00001465; URL: www.clinicaltrials.gov

Initial presentation of lymphangioleiomyomatosis in third trimester of pregnancy

Lymphangioleiomyomatosis (LAM) is a progressive cystic lung disease which mostly affects premenopausal women and could be exacerbated by pregnancy. Therefore, it is thought that oestrogen plays an important role in LAM pathogenesis. Here, a case of LAM is described in which the first presentation of symptoms occurred during the third trimester of pregnancy. Symptoms included acute onset dyspnoea and chest pain at gestational age of 39 weeks and 2 days. A CT was performed which showed multiple thin-walled cysts and a small pneumothorax. Serum levels of vascular endothelial growth factor-D (VEGF-D) was 1200 pg/mL. The typical cystic lung changes on chest CT in combination with elevated VEGF-D is diagnostic for LAM. Given the risk of respiratory complications, the decision was made to deliver the baby at a gestational age of 39 weeks and 6 days by a planned caesarean section. Both mother and child were discharged home in good condition.

Risk factors for right ventricular dysfunction in patients with lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare disease characterized by diffuse cystic lesions of the lung. The present study was designed to evaluate the right ventricular (RV) function in LAM patients via single-beat real-time three-dimensional echocardiography (RT-3DE) and to investigate the factors affecting RV function in LAM patients. According to tricuspid regurgitation velocity (TRV), forty-five female LAM patients [(44.07 ± 10.22) years old] were divided into TRV ≤ 2.8 m/s group (n = 29) and TRV > 2.8 m/s group (n = 16). Relative echocardiography parameters were assessed by conventional transthoracic echocardiography, Doppler tissue imaging (DTI) and RT-3DE, respectively. Pulmonary function tests and the six-minute walk tests (SMWT) were also performed for LAM patients. We found that most of RV functional parameters in LAM patients were worse than that in control patients, although left ventricular dysfunction was not significantly observed. Correlation analysis showed that 3D echocardiographic RV ejection fraction (RVEF) was negatively correlated with pulmonary vascular resistance (PVR), TRV, and the decrease of oxygen saturation (SpO₂) post SMWT, and positively correlated with Forced expiratory volume in the first second/forced vital capacity, carbon monoxide diffusion predicted value, SMWT distance, and resting SpO₂ in LAM patients. Multivariate stepwise linear regression analysis showed that PVR and SpO2 before SMWT were independent influence factors of RVEF in LAM patients. In this study, we found that RV dysfunction was presented in LAM patients, although left ventricular dysfunction was not significantly obvious. The main influence factors of RVEF were PVR and hypoxia. RT-3DE is a low-cost and noninvasive way to evaluate RV function in LAM patients.

Investigating cystic lung disease: a respiratory detective approach

The cystic lung diseases are rare orphan lung disorders that most physicians will see infrequently in their everyday practice. Diagnostic and treatment options have improved over recent decades, with opportunities for slowing rate of progression and improving outcome for patients. This review provides a summary of the clinical approach to these lung disorders, including how to differentiate between different imaging patterns, clinical features, differential diagnosis and characteristics of the commonest presenting disorders.

Cystic lung diseases are uncommon disorders with a wide differential diagnosis. Treatment has improved over the last decade and respiratory physicians should feel encouraged to investigate such cases thoroughly to reach a final diagnosis.https://bit.ly/2W6Is9D

Sex-Based Differences in Interstitial Lung Disease

Interstitial lung diseases comprise a family of progressive pulmonary disorders that are often idiopathic or associated with various systemic diseases and that is characterized by bilateral lung involvement with inflammation and tissue remodeling or fibrosis. The impact of sex, including the anatomic and physiologic traits that one is born with, on the development and progression of interstitial lung diseases is not entirely clear. Variances between men and women are driven by differences in male and female biology and sex hormones, among other differences, but their role remains uncertain. In this review, we summarize sex-related differences in the epidemiology and progression of certain interstitial lung diseases with a focus on the connective tissue related interstitial lung diseases, idiopathic pulmonary fibrosis, and sarcoidosis. We also discuss cellular and pre-clinical studies that might shed light on the potential mechanisms responsible for these differences in the hope of unveiling potential targets for intervention and stimulating research in this needed field of investigation.

Clinical CT underestimation of the percentage volume occupied by cysts in patients with lymphangioleiomyomatosis

PURPOSE

To evaluate the accuracy of cyst score measurements by standard high-resolution helical volume chest CT (HRCT) in patients with lymphangioleiomyomatosis (LAM), using a short z-length ultra-high resolution re-scan (UH re-scan) as the reference. In cystic lung diseases, cyst score is derived from CT scans and defined as the percentage of the total lung parenchymal volume occupied by cysts, a biomarker which measures the severity of the disease.

METHODS

In a prospective study of 73 LAM patients, each patient received the standard HRCT chest scan and a short z-length UH re-scan. Cyst scores were acquired from both scans using a standard FDA-approved scoring software on the CT scanner.

RESULTS

The limited UH re-scan resolved small cysts that were not resolved in the HRCT. The HRCT-derived cyst scores were on average 59.6% of the reference values from the UH re-scan (p = 4.7e-25). The amount of under-estimation by HRCT varied from patient to patient, with an inter-quartile range of 29.8% and standard deviation of 20.7%. The overall trend was more pronounced underestimation for patients with lower cyst scores. For patients whose reference cyst scores were below 15 (n = 29), the HRCT cyst scores were 46.9 ± 21.6% of reference values (p = 7.4e-12), while for the rest of the patients (n = 44) the HRCT cyst scores were 68.0 ± 15.3% of reference values (p = 1.2E-19). Reconstructing the HRCT images to the resolution of the UH re-scan further widened the spread of the discrepancy between HRCT and reference values due to increased image noise, and did not provide accurate cyst scores.

CONCLUSION

Cyst scores derived from standard high-resolution helical volume chest CT significantly underestimates the percentage lung volume occupied by cysts. This inaccuracy needs to be taken into consideration when cyst score is used as part of the CT assessment of the patient's condition.

Role of thoracic imaging in the management of lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare diffuse lung cystic disease (DLCD) that occurs sporadically or in association with Tuberous Sclerosis Complex (TSC). The diagnostic pathway is tracked on the identification of the disease hallmarks on chest High-Resolution Computed Tomography (HRCT). Aim of this review is to discuss the thoracic HRCT pathognomonic features, essential to rule out other DLCD. It also examines the new evidences emerging from Computed Tomography (CT) quantitative studies that, by demonstrating a specific cysts distribution and a pathological aspect of the parenchyma near the cysts, could improve our understanding of this rare disorder and supply pulmonologists with a new tool for a more appropriate long-term management. Finally, the contribution of other image techniques as low dose chest CT, Magnetic Resonance Imaging (MRI) and Ultrasound (US) is discussed.

Long-term efficacy and safety of sirolimus therapy in patients with lymphangioleiomyomatosis

BACKGROUND

Sirolimus has been confirmed to be effective for lymphangioleiomyomatosis (LAM), a rare multisystem neoplastic disease in women. The long-term effects of sirolimus treatment for LAM, however, are largely unknown. We aimed to analyze the long-term efficacy and safety of sirolimus therapy for LAM with 4-year follow-up.

METHODS

In total, 142 sporadic LAM patients who took sirolimus for 1-4 years were retrospectively enrolled for this analysis. The variables used for analysis included pulmonary function tests, arterial blood gas analysis, 6-min walking distance (6MWD), St. George's Respiratory Questionnaires (SGRQ) and serum vascular endothelial growth factor-D (VEGF-D) levels before and after the initiation of sirolimus therapy. The rates of change (slope) in those variables were calculated, and adverse events were also analyzed.

RESULTS

In total, 122, 83, 60 and 32 patients out of 142 were followed for 1, 2, 3 and 4 years respectively. Sirolimus treatment improved the change rate in forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC) compared with the data before treatment (FEV₁, - 10 ± 15 vs. - 178 ± 36 ml/y, P <  0.001 and FVC, 54 ± 22 vs.-72 ± 68 ml/y, P < 0.05). In comparison to the baseline measurements, significant improvements were observed in FEV₁ at the first year; FVC at 1-2 years; arterial oxygen levels, 6MWD, and SGRQ at 1-3 years; and VEGF-D at 1-4 years. Overall, all variables stabilized or improved during the 4 years of observation. Adverse events related to sirolimus were mild.

CONCLUSION

Sirolimus therapy is effective at improving or stabilizing pulmonary function, oxygen levels, exercise capacity, and quality of life in patients with LAM for up to 4 years. VEGF-D is maintained at a lower level for 4 years after treatment. Adverse events related to sirolimus were mild.

Safe and effective use of nivolumab for treating lung adenocarcinoma associated with sporadic lymphangioleiomyomatosis: a rare case report

BACKGROUND

Sporadic lymphangioleiomyomatosis (LAM) is a rare form of diffuse parenchymal lung disease. PD-1 blocking antibodies constitute an essential treatment option for advanced non-small-cell lung cancer (NSCLC). The effect of immune checkpoint inhibitors in lymphangioleiomyomatosis patients with non-small cell lung cancer is unknown: concomitant symptomatic interstitial lung disease or the use of immunosuppressors was a key exclusion criterion in the original studies of immune checkpoint inhibitors, especially regarding the risk of interstitial lung disease exacerbation.

CASE PRESENTATION

A 48-year-old female, active smoker (36 pack-years), diagnosed with sporadic LAM since 2004 suffered from metastatic adenocarcinoma of the lung. Third-line therapy with nivolumab was started in 2015, with a major partial response. Due to pulmonary function alterations, sirolimus was also reinitiated in 2017 in conjunction with nivolumab, without any undesirable effects and a major partial response continuing up to May 2018.

CONCLUSIONS

This case highlights the safe and effective use of nivolumab for managing metastatic lung adenocarcinoma that occurred in a patient with sporadic LAM. In the current case, immunotherapy proved highly successful in managing the NSCLC tumor that occurred upon LAM follow-up, with both a significantly prolonged partial response and acceptable safety profile.

Interstitial Lung Disease and Pulmonary Fibrosis: A Practical Approach for General Medicine Physicians with Focus on the Medical History

Interstitial lung disease (ILD) and pulmonary fibrosis comprise a wide array of inflammatory and fibrotic lung diseases which are often confusing to general medicine and pulmonary physicians alike. In addition to the myriad of clinical and radiologic nomenclature used in ILD, histopathologic descriptors may be particularly confusing, and are often extrapolated to radiologic imaging patterns which may further add to the confusion. We propose that rather than focusing on precise histologic findings, focus should be on identifying an accurate etiology of ILD through a comprehensive and detailed medical history. Histopathologic patterns from lung biopsy should not be dismissed, but are often nonspecific, and overall treatment strategy and prognosis are likely to be determined more by the specific etiology of ILD rather than any particular histologic pattern. In this review, we outline a practical approach to common ILDs, highlight important aspects in obtaining an exposure history, clarify terminology and nomenclature, and discuss six common subgroups of ILD likely to be encountered by general medicine physicians in the inpatient or outpatient setting: Smoking-related, hypersensitivity pneumonitis, connective tissue disease-related, occupation-related, medication-induced, and idiopathic pulmonary fibrosis. Accurate diagnosis of these forms of ILD does require supplementing the medical history with results of the physical examination, autoimmune serologic testing, and chest radiographic imaging, but the importance of a comprehensive environmental, avocational, occupational, and medication-use history cannot be overstated and is likely the single most important factor responsible for achieving the best possible outcomes for patients.

Efficacy and safety of low-dose Sirolimus in Lymphangioleiomyomatosis

BACKGROUND

Lymphangioleiomyomatosis is a rare disease caused by unregulated activation of mammalian target of rapamycin (mTOR) signalling pathway. Sirolimus showed efficacy in a phase 3 trial of patients with lymphangioleiomyomatosis, but the optimal dose remains unclear.

METHODS

We investigated the efficacy and safety of low-dose compared with conventional-dose sirolimus. Clinical data of 39 patients with lymphangioleiomyomatosis (mean age, 34.8 years; median treatment period, 29.6 months) who received sirolimus were retrospectively reviewed. Low-dose sirolimus was defined as any dose that maintained mean blood trough levels lower than those maintained with conventional doses (5-15 ng/mL).

RESULTS

Fifty-one percent of patients received low-dose therapy. The rate of decline in lung function decreased after treatment in the whole group (forced expiratory volume in 1 s [FEV₁], - 0.12 ± 0.47 [before] vs. 0.24 ± 0.48% predicted/month [after], p = 0.027; diffusing capacity for carbon monoxide [DLco], - 0.33 ± 0.61 vs. 0.03 ± 0.26% predicted/month, p = 0.006) compared with before treatment. In the low-dose group, the rate of decline in FEV₁ (- 0.08 ± 0.38 [before] vs. 0.19 ± 0.51% predicted/month [after], p = 0.264) and DLco (-0.13 ± 0.62 vs. 0.02 ± 0.28% predicted/month, p = 0.679) showed a numeric trend towards improvement after treatment; however, the conventional-dose group showed significant improvement in FEV₁ (- 0.26 ± 0.54 [before] vs. 0.22 ± 0.38 [after] % predicted/month, p = 0.024) and DLco (- 0.55 ± 0.58 vs. 0.04 ± 0.25% predicted/month, p = 0.002) after treatment. Adverse events (AEs) occurred in 89.7% of patients and the most common AEs was hypercholesterolaemia (43.6%), followed by stomatitis (35.9%). The occurrences of AE were similar between the low- and conventional-dose groups (85.0% vs. 94.7%, p = 0.605).

CONCLUSIONS

Low-dose sirolimus may stabilise lung function decline in lymphangioleiomyomatosis patients, but its efficacy appears to be inferior to that of conventional-dose sirolimus.

A new drug combination significantly reduces kidney tumor progression in kidney mouse model

Tuberous sclerosis complex (TSC) disease is associated with tumors in many organs, particularly angiomyolipoma (AML) in the kidneys. Loss or inactivation of TSC1/2 results in high levels of HIF-α activity and VEGF expression. mTOR inhibitor (rapamycin) and the AMPK activator 5-aminoimidazole-4-carboxamide (AICA)-riboside (AICAR) are currently used separately to treat cancer patients. Here, we investigated the effect of a novel combination of rapamycin and AICAR on tumor progression. Our data show that treatment of AML human cells with drug combinations resulted in 5-7-fold increase in cell apoptosis compared to each drug alone. In addition, drug combinations resulted in 4-5-fold decrease in cell proliferation compared to each drug alone. We found that drug combinations abolished Akt and HIF activity in AML cells. The drug combinations resulted in decrease in cell invasion and cell immigration by 70% and 84%, respectively in AML cells. The combined drugs also significantly decreased the VEGF expression compare to each drug alone in AML cells. Drug combinations effectively abolished binding of HIF-2α to the putative Akt site in the nuclear extracts isolated from AML cells. Treatment TSC mice with drug combinations resulted in 75% decrease in tumor number and 88% decrease in tumor volume compared to control TSC mice. This is first evidence that drug combinations are effective in reducing size and number of kidney tumors without any toxic effect on kidney. These data will provide evidence for initiating a new clinical trial for treatment of TSC patients.

Pseudoneutropenia in lymphangioleiomyomatosis (LAM) patients receiving sirolimus: evaluation in a 100 patient cohort

Diurnal variation in white blood cells (WBC), particularly neutrophils, is well-described [1]. WBC levels are lower in the morning and increase through the day [1, 2]. Drugs with immunosuppressive effects, such as sirolimus, may further lower WBC counts. This phenomenon has been observed in clozapine and related atypical antipsychotic medications, drugs with known immunosuppressive effects [3, 4]. For patients receiving these drugs, blood counts measured in the early morning may lead to a false impression of low WBC/neutrophil counts (“pseudoleukopenia/pseudoneutropenia”) [4–8] that may result in discontinuation or a reduction in dose and suboptimal treatment. Of importance, isolated morning neutropenia is not known to increase the risk of infection [6, 9].

In lymphangioleiomyomatosis patients receiving sirolimus treatment, transient leukopenia in the morning may be due to circadian rhythm, with leukocyte counts recovering later in the day, indicating that a decrease in drug dose may not be warrantedhttp://ow.ly/jPFz30iysgV

Sirolimus Therapy for Patients With Lymphangioleiomyomatosis Leads to Loss of Chylous Ascites and Circulating LAM Cells

A young woman received a diagnosis of abdominal, sporadic lymphangioleiomyomatosis (LAM) and multiple abdominal lymphangioleiomyomas and was referred for recurrent chylous ascites responding only to a fat-free diet. On admission, pulmonary function test (PFT) results showed a moderate reduction in the transfer factor for carbon monoxide with normal exercise performance. The serum vascular endothelial growth factor D (VEGF-D) level was 2,209 pg/mL. DNA sequences, amplified at loci kg8, D16S3395, D16S3024, D16S521, and D16S291 on chromosome 16p13.3, showed a loss of heterozygosity (LOH) only for kg8. Fat-free total parenteral nutrition in association with sirolimus (2 mg po daily) was initiated. Serum sirolimus levels were maintained at concentrations between 5 and 15 ng/mL. After 1 month, reintroduction of a low-fat oral feeding was achieved without recurrence of ascites. PFT results were stable. Interestingly, clinical improvement was associated with a reduction in the VEGF-D serum level (1,558 pg/mL). LOH at the kg8 biomarker in blood LAM cells was no longer detected.

Thoracic involvement in generalised lymphatic anomaly (or lymphangiomatosis)

Generalised lymphatic anomaly (GLA), also known as lymphangiomatosis, is a rare disease caused by congenital abnormalities of lymphatic development. It usually presents in childhood but can also be diagnosed in adults. GLA encompasses a wide spectrum of clinical manifestations ranging from single-organ involvement to generalised disease. Given the rarity of the disease, most of the information regarding it comes from case reports. To date, no clinical trials concerning treatment are available. This review focuses on thoracic GLA and summarises possible diagnostic and therapeutic approaches.

Possible diagnostic and therapeutic approaches to generalised lymphatic anomaly (lymphangiomatosis)http://ow.ly/4n4pgU

Diagnosis and treatment of cystic lung disease

Cystic lung disease (CLD) is a group of lung disorders characterized by the presence of multiple cysts, defined as air-filled lucencies or low-attenuating areas, bordered by a thin wall (usually < 2 mm). The recognition of CLDs has increased with the widespread use of computed tomography. This article addresses the mechanisms of cyst formation and the diagnostic approaches to CLDs. A number of assessment methods that can be used to confirm CLDs are discussed, including high-resolution computed tomography, pathologic approaches, and genetic/ serologic markers, together with treatment modalities, including new therapeutic drugs currently being evaluated. The CLDs covered by this review are lymphangioleiomyomatosis, pulmonary Langerhans cell histiocytosis, Birt-Hogg-Dube syndrome, lymphocytic interstitial pneumonia/follicular bronchiolitis, and amyloidosis.

Lung ultrasound has limited diagnostic value in rare cystic lung diseases: a cross-sectional study

Background: Lung ultrasound (LUS) used to identify interstitial syndrome (IS) and pleural thickening related to diffuse parenchymal lung disease (DPLD) has shown significant correlations with ground glass opacity (GGO) on high-resolution computed tomography (HRCT). However, the applicability of LUS in patients with DPLD subtypes as rare cystic lung diseases has not previously been investigated. This study aimed to observe if distinctive LUS findings could be found in patients with lymphangioleiomyomatosis (LAM), pulmonary Langerhans cell histiocytosis (PLCH), and Birt-Hogg-Dubé syndrome (BHDS). Methods: This single centre case-based cross-sectional study of patients diagnosed with LAM, PCLH and BHDS was conducted at a Danish DPLD specialist centre. Patients underwent clinical examination including LUS. LUS findings were compared to findings scored according to a modified Belmaati score on HRCT and reviewed in consensus between two pulmonologists and one radiologist. Results: Twelve patients with HRCT proven cystic lung disease were included, six with LAM, three with PLCH, two with BHDS, and one with uncharacteristic cystic lung disease. The mean age was 48.7 years (SD ± 15.8). In general all had normal LUS findings. IS could not be found in any patients despite GGO presentation on HRCT among 75% of the patients with a Belmaati in the highest category of 0.76-1.00. Pleural thickening on LUS was present in three patients, but with inconsistent findings. Conclusion: This study indicates that LUS has limited value as a diagnostic tool in patients with LAM, PLCH, and BHDS as normal LUS findings did not rule out severe cystic lung disease.

Lung disease recalling paraseptal emphysema in a patient with Goltz syndrome

Background

Goltz syndrome is a rare, genetic disorder mainly occurring in female patients.

Case presentation

The case presented here is, to the best of our knowledge, the first description of the occurrence of lung parenchymal alterations in a young female patient affected by Goltz syndrome. Although pulmonary involvement is not known in patients affected by X-linked Goltz syndrome, the case here described is related to the even rarer autosomal form of the disease, as in this case. It is thus conceivable that in such different genetic setting the involvement of lung parenchyma may be unveiled through atypical emphysematous lesions.

Conclusion

This report suggested - for the first time time - a rationale for a lung function and imaging screening in patients affected by Goltz syndrome at least in its autosomal form.

Is mTOR Inhibitor Good Enough for Treatment All Tumors in TSC Patients?

Tuberous sclerosis complex (TSC) is an autosomal dominant and multi-system genetic disorder in humans. TSC affects around 25,000 to 40,000 individuals in the United States and about 1 to 2 million individuals worldwide, with an estimated prevalence of one in 6,000 newborns. TSC occurs in all races and ethnic groups, and in both genders. TSC is caused by defects or mutations in two genes, TSC1 and TSC2. Loss of TSC1/TSC2 leads to dysregulation of mTOR, resulting in aberrant cell differentiation and development, and abnormal enlargement of cells. TSC is characterized by the development of benign and/or malignant tumors in several organs including renal/liver angiomyolipomas, facial angiofibroma, lymphangiomyomatosis, cardiac rhabdomyomas, retinal astrocytic, renal cell carcinoma, and brain subependymal giant cell astrocytomas (SEGA). In addition, TSC disease causes disabling neurologic disorders, including epilepsy, mental retardation and autism. Particularly problematic are the development of renal angiomyolipomas, which tend to be larger, bilateral, multifocal and present at a younger age compared with sporadic forms. In addition, SEGA block the flow of fluid within the brain, causing a buildup of fluid and pressure that leads to blurred vision and seizures. In the current review, we describe the pathology of TSC disease in key organs and summarize the use of mTOR inhibitors to treat tumors in TSC patients.