Longitudinal follow-up study of 11 patients with pulmonary lymphangioleiomyomatosis: diverse clinical courses of LAM allow some patients to be treated without anti-hormone therapy

Lymphangioleiomyomatosis Diagnosis and Management: High-Resolution Chest Computed Tomography, Transbronchial Lung Biopsy, and Pleural Disease Management. An Official American Thoracic Society/Japanese Respiratory Society Clinical Practice Guideline

BACKGROUND

Recommendations regarding key aspects related to the diagnosis and pharmacological treatment of lymphangioleiomyomatosis (LAM) were recently published. We now provide additional recommendations regarding four specific questions related to the diagnosis of LAM and management of pneumothoraces in patients with LAM.

METHODS

Systematic reviews were performed and then discussed by a multidisciplinary panel. For each intervention, the panel considered its confidence in the estimated effects, the balance of desirable (i.e., benefits) and undesirable (i.e., harms and burdens) consequences, patient values and preferences, cost, and feasibility. Evidence-based recommendations were then formulated, written, and graded using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach.

RESULTS

For women who have cystic changes on high-resolution computed tomography of the chest characteristic of LAM, but who have no additional confirmatory features of LAM (i.e., clinical, radiologic, or serologic), the guideline panel made conditional recommendations against making a clinical diagnosis of LAM on the basis of the high-resolution computed tomography findings alone and for considering transbronchial lung biopsy as a diagnostic tool. The guideline panel also made conditional recommendations for offering pleurodesis after an initial pneumothorax rather than postponing the procedure until the first recurrence and against pleurodesis being used as a reason to exclude patients from lung transplantation.

CONCLUSIONS

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

Reductions in pulmonary function detected in patients with lymphangioleiomyomatosis: An analysis of the Japanese National Research Project on Intractable Diseases database

BACKGROUND

In lymphangioleiomyomatosis (LAM), predicting lung disease progression is essential for treatment planning. However, no previous Japanese studies have attempted to predict the reductions in pulmonary function that occur in LAM patients.

METHODS

The data for 89 LAM patients who had undergone ≥3 spirometry tests and whose data had been registered in the Japanese National Research Project on Intractable Diseases database between October 2009 and March 2014 were analyzed after excluding patients who had undergone (1) a lung transplant; (2) mTOR inhibitor treatment; or (3) thoracic drainage, pleurodesis, surgery, or thoracic duct ligation during the study period. The rates of change (slope) in pulmonary parameters were calculated, and their associations with clinical background factors were investigated.

RESULTS

Among the whole study population, the median (quartiles) slope of forced expiratory volume in one second (FEV1) was -46.7 (-95.2; -15.0)mL per year. Episodes of conservatively treated pneumothorax during the study period were found to be associated with rapid reductions in FEV1 (% predicted). Pregnancy during the study period was associated with a reduction in FEV1 (% predicted). When the patients were divided into those who exhibited initial FEV1 (% predicted) values of >70% (Group A) and ≤70% (Group B), Group B displayed significantly faster reductions in FEV1 (% predicted) than Group A.

CONCLUSIONS

LAM patients whose initial FEV1 (% predicted) values are ≤70% subsequently exhibit rapid reductions in their FEV1 values, and hence, require treatment. However, the FEV1 reduction rate varies markedly among individuals and should be monitored in all cases.

Progesterone and estradiol synergistically promote the lung metastasis of tuberin-deficient cells in a preclinical model of lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a female-predominant lung disease that can lead to respiratory failure. LAM cells typically have inactivating tuberous sclerosis 2 (TSC2) mutations, leading to mTORC1 hyperactivation. The gender specificity of LAM suggests that female hormones contribute to disease progression. Clinical findings indicate that estradiol exacerbates LAM behaviors and symptoms. Although hormonal therapy with progesterone has been employed, the benefit in LAM improvement has not been achieved. We have previously found that estradiol promotes the survival and lung metastasis of cells lacking tuberin in a preclinical model of LAM. In this study, we hypothesize that progesterone alone or in combination with estradiol promotes metastatic behaviors of TSC2-deficient cells. In cell culture models of TSC2-deficient LAM patient-derived and rat uterine leiomyoma-derived cells, we found that progesterone treatment or progesterone plus estradiol resulted in increased phosphorylation of Protein Kinase B (Akt) and Extracellular signal-regulated kinases1/2 (ERK1/2), induced the proliferation, and enhanced the migration and invasiveness. In addition, treatment of progesterone plus estradiol synergistically decreased the levels of reactive oxygen species and enhanced cell survival under oxidative stress. In a murine model of LAM, treatment of progesterone plus estradiol promoted the growth of xenograft tumors; however, progesterone treatment did not affect the development of xenograft tumors of Tsc2-deficient cells. Importantly, treatment of progesterone plus estradiol resulted in alteration of lung morphology and significantly increased the number of lung micrometastases of Tsc2-deficient cells compared with estradiol treatment alone. Collectively, these data indicate that progesterone increases the metastatic potential of Tsc2-deficient LAM patient-derived cells in vitro and lung metastasis in vivo. Thus, targeting progesterone-mediated signaling events may have therapeutic benefit for LAM and possibly other hormonally dependent cancers.

Two cases of pulmonary lymphangioleiomyomatosis in postmenopausal women

Pulmonary lymphangioleiomyomatosis is a rare disease that occurs exclusively in young women, who typically present with progressive dyspnea and repeated spontaneous pneumothorax. The diagnosis of this disease in elderly women with a non-progressive clinical course is extremely rare. We herein report two incidentally discovered cases of pulmonary lymphangioleiomyomatosis in postmenopausal patients. These patients had not presented with any respiratory symptoms. Lymphangioleiomyomatosis may be related to hormonal influences; however, the etiology and pathogenesis of the pulmonary lesions that develop in postmenopausal females are unclear, even after a review of the literature.

Utility of transbronchial biopsy in the diagnosis of lymphangioleiomyomatosis

Pulmonary lymphangioleiomyomatosis (LAM) is a rare cystic lung disease that targets women during their reproductive years. A confident diagnosis can often be based on clinical grounds, but diagnostic certainty requires pathological analysis. Although surgical lung biopsy is considered the gold standard for obtaining tissue in patients with diffuse lung disease, it is also associated with higher morbidity and mortality than alternative, less invasive techniques. The objective of our study was to examine the utility of transbronchial biopsy in the diagnosis of LAM. We conducted two online surveys of over 1,000 LAM patients registered with the LAM Foundation who were accessible by email. Transbronchial biopsy specimens were subsequently collected and reviewed by an expert pathologist to validate the diagnosis. We found that transbronchial biopsy has a yield of approximately 60% in patients with LAM. We conclude that transbronchial biopsy may be a safe and effective method for establishing the diagnosis of LAM, obviating the need for surgical lung biopsy in more than half of LAM patients.

Clinical analysis of patients with pulmonary lymphangioleiomyomatosis (PLAM) in mainland China

BACKGROUND AND OBJECTIVE

There have been no clinical reports on pulmonary lymphangioleiomyomatosis (PLAM) based on large studies or epidemiological surveys in mainland China. The purpose of this study was to provide a retrospective analysis of PLAM patients in mainland China by reviewing the clinical data of PLAM cases reported.

METHODS

The China Academic Journals Full-text Database search engine was used to collect related cases in mainland China through the end of 2008. 120 cases met the study's inclusion criteria and were reviewed for this analysis.

RESULTS

The average age of the 120 patients upon confirmed diagnosis was 37.3+/-6.4 years. The average duration from onset of symptoms to a confirmed diagnosis was 29.6+/-35.8 months, with 80 person-time patients having experienced misdiagnosis before the confirmed diagnosis. The major clinical manifestations of PLAM included progressive dyspnea, recurrent pneumatothorax, refractory chylothorax. Pulmonary function abnormalities included obstructive pulmonary ventilation disorders and degenerated diffusing capacity. Ten patients were found to be complicated with renal angiomyolipoma and 17 with abdominal or pelvic lymphangioleiomyoma. Half of the patients had undergone antiestrogen therapies such as progesterone, and four patients received pulmonary transplantation. The average duration from the confirmed diagnosis to death was 36.4+/-48.9 months among the 28 cases of death.

CONCLUSIONS

Doctors in mainland China are becoming increasingly vigilant to PLAM, although misdiagnosis or missed diagnosis still exists. Provider attention to the correlation between PLAM and tuberous sclerosis complex, as well as to the possible involvement of multiple organs, is insufficient.

The epidemiology of lymphangioleiomyomatosis in Japan: a nationwide cross-sectional study of presenting features and prognostic factors

BACKGROUND AND OBJECTIVE

To evaluate the characteristics and prognostic factors of Japanese patients with lymphangioleiomyomatosis (LAM).

METHODS

A nationwide survey to identify patients with LAM was conducted by questionnaire. Survival probability was estimated using the Kaplan-Meier method, and the prognostic factors were analysed by Cox regression.

RESULTS

Data were collected on 173 patients with pulmonary LAM. The major presenting features were pneumothorax (43%) and exertional dyspnoea (37%). The survival probabilities for patients presenting with exertional dyspnoea (Group A) were 85%, 60% and 47% after 5, 10 and 15 years, respectively, and for patients presenting with pneumothorax (Group B) were 95%, 89% and 89%, respectively. Although the age at symptom onset was higher among patients in Group A than in Group B, Cox regression revealed that the presenting feature was a prognostic factor independent of age at symptom onset (Group A/B hazard ratio = 5.732, P < 0.01). In the subgroup of patients whose initial FEV(1) was >1000 mL, or FEV(1)/FVC >40%, or %DL(CO) >40%, the rate of deterioration in these tests was greater in Group A than in Group B (P < 0.01 for FEV(1), P < 0.05 for FEV(1)/FVC and %DL(CO)).

CONCLUSIONS

There are two possible subgroups of LAM patients. One subgroup that presented with pneumothorax, had onset of symptoms at a younger age and a more favourable prognosis; the other presented with exertional dyspnoea, had onset of symptoms at an older age and a poorer prognosis.

Vascular endothelial growth factor-D is increased in serum of patients with lymphangioleiomyomatosis

BACKGROUND

Lymphangioleiomyomatosis (LAM) is a rare destructive lung disease characterized by an abnormal proliferation of smooth muscle-like cells (LAM cells) in the lung and along the axial lymphatics. LAM demonstrates a heterogeneous clinical course, but there is no serum surrogate marker available for assessing the disease severity or predicting the disease progression. Since the authors have recently demonstrated the extensive LAM-associated lymphangiogenesis and its potential role in progression and metastasis of LAM cells, they hypothesized that serum levels of lymphangiogenic growth factors might be increased in LAM and become a surrogate marker for disease severity.

METHODS AND RESULTS

VEGF-A, VEGF-C, and VEGF-D in serum of 44 patients with LAM were measured by enzyme-linked immunosorbant assay. Only VEGF-D was significantly increased in LAM patients as compared with age- and gender-matched healthy volunteers (n=24) (LAM vs. control, geometric mean 95% CI; 1069.3 pg/mL (809.4 approximately 1412.6) vs. 295.9 pg/mL (262.6 approximately 333.5), p<0.0001). Serum VEGF-D levels negatively correlated with variables of pulmonary function tests, FEV1/FVC (forced expiratory volume in one second/forced vital capacity) (r=-0.365, p<0.05) and %DLco/VA (the percentage of diffusing capacity for carbon monoxide/alveolar volume to the predicted value) (r=-0.560, p<0.001). As expected, the group who received hormone therapy showed more deteriorated pulmonary function with higher serum VEGF-D levels than the group who was just observed without hormone therapy. Immunohistochemical examination of lung specimens demonstrated the positive immunoreactivity of LAM cells for VEGF-D.

CONCLUSION

Serum VEGF-D levels may be a valuable surrogate marker for evaluating the disease severity in LAM.

Pleural disease in lymphangioleiomyomatosis

Pleural disease is a common complication of lymphangioleiomyomatosis (LAM). The incidence and recurrence rates of secondary spontaneous pneumothorax in LAM are the highest among chronic pulmonary disorders. Most patients have at least one pneumothorax before LAM is diagnosed, and pneumothorax is often the sentinel event that leads to the diagnosis. Although early, definitive treatment for recurrent pneumothorax by pleurodesis is recommended, the failure rate for chemical and surgical approaches is high. Chylothorax occurs owing to obstruction of lymphatics by proliferating smooth muscle cells and often requires pleurodesis to control expanding and recurrent effusions. Because of the rarity of the LAM, few data exist on whether the occurrence of pleural complications in LAM accelerates functional decline or portends a worse prognosis.

Lymphangiogenesis-Mediated Shedding of LAM Cell Clusters as a Mechanism for Dissemination in Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) affects exclusively women of reproductive age, involves the lungs and axial lymphatic system, and is frequently complicated with renal angiomyolipomas. LAM lesions are generated by the proliferation of LAM cells with mutations of one of the tuberous sclerosis complex (TSC) genes. Recent studies indicate that LAM cells can migrate or metastasize to form new lesions in multiple organs, although they show a morphologically benign appearance. In the previous study, we reported LAM-associated lymphangiogenesis and implicated its role in the progression of LAM. In this study, we further focused on the lymphatic abnormalities in LAM: LAM-associated chylous fluid (5 pleural effusion and 2 ascites), surgically resected diaphragm (1 patient), and axial lymphatic system including the thoracic duct, lymph nodes at various regions, and diaphragmatic lymphatic system (5 autopsy cases). We demonstrated that LAM cell clusters enveloped by lymphatic endothelial cells (LCC) in all chylous fluid examined. We identified LAM lesion in the diaphragm (2 of 5 autopy cases and one surgical specimen), thoracic duct (5 of 5), and lymph nodes (retroperitoneal (5 of 5), mediastinal (4 of 5), left venous angle (5 of 5) with total positive rate of 68% to 88% at each region of the lymph node, but less frequent or none at remote lymph nodes located away from the axial lymph trunk (cervical [1 of 5] and axillary [0 of 5]). LCCs were identified in intra-LAM lesional lymphatic channels where LAM cells proliferate along lymphatic system. In in vitro culture system, LCC can fragment into each proliferating LAM cell. These findings suggest that LAM-associated lymphangiogenesis demarcates LAM lesion into bundle- or fascicle-like structure and eventually shed LCC into the lymphatic circulation and that LCCs play a central role in the dissemination of LAM lesion.

Emerging clinical picture of lymphangioleiomyomatosis

OBJECTIVE

To provide a comprehensive update of the clinical picture of lymphangioleiomyomatosis (LAM) using two large patient registries.

METHODS

A cross sectional questionnaire survey which included questions on 14 LAM symptoms, pneumothorax, tuberous sclerosis complex (TSC), date of diagnosis, and pulmonary function tests (PFTs).

RESULTS

The response rate was 70.5% (n = 328). The mean age at the time of the survey was 46.7 years. The mean age at diagnosis was 42.7 years for women diagnosed 1 year before the survey and 35.8 years for women diagnosed 10 years previously. The main symptoms were dyspnoea (74%), fatigue (72%), cough (47%) and chest pain (44%); younger patients (<40 years) were less likely to report dyspnoea (p = 0.02). Patients with TSC (n = 51) were less likely to report dyspnoea (p = 0.05) and 76.5% reported angiomyolipoma (p < 0.0001) compared with patients with sporadic LAM. Patients with pneumothorax (63.0%) were less likely to report dyspnoea or fatigue (p < or = 0.05) than patients without pneumothorax. PFT results showed that low forced expiratory volume in 1 second and carbon monoxide transfer factor were highly associated with dyspnoea (p < 0.0001), but not with fatigue or history of pneumothorax.

CONCLUSION

Previously considered a condition of women of childbearing age, more older women (50% without pneumothorax) are now being diagnosed with LAM. LAM should be considered in women over 40 with unexplained dyspnoea. LAM patients with pneumothorax have less fatigue and less dyspnoea than those without pneumothorax. Fatigue has been overlooked as a symptom of LAM and appears across the spectrum of pulmonary function.

Decline in lung function in patients with lymphangioleiomyomatosis treated with or without progesterone

STUDY OBJECTIVE

Lymphangioleiomyomatosis (LAM), a disease affecting women and causing cystic lung lesions, and, in some instances, leading to respiratory failure and death, appears to be exacerbated by estrogens. Hence, hormonal therapy with progesterone is frequently employed; however, efficacy has not been demonstrated. Our aim was to determine whether progesterone administration slowed the decline in lung function in LAM.

DESIGN

Retrospective study.

SETTING

National Institutes of Health, Bethesda, MD.

DESIGN AND SUBJECTS

The study population comprised 348 patients with LAM participating in a longitudinal research protocol. Declines in diffusion capacity of the lung for carbon monoxide (Dlco) and FEV(1) were measured in 275 patients observed for approximately 4 years. The declines in Dlco and FEV(1) of patients treated with progesterone, po (n = 67) or IM (n = 72), were compared with those of untreated patients (n = 136).

MEASUREMENTS AND RESULTS

Overall yearly rates of decline in Dlco and FEV(1) were 2.4 +/- 0.4% predicted (0.69 +/- 0.07 mL/min/mm Hg) and 1.7 +/- 0.4% predicted (75 +/- 9 mL), respectively (mean +/- SEM). The most significant predictors of functional decline were initial lung function and age. After adjusting for initial FEV(1), age, and duration of disease, patients treated with IM progesterone tended to have lower rates of decline in FEV(1) than patients treated po (1.9 +/- 0.6% predicted vs 3.2 +/- 0.8% predicted, respectively; p = 0.081). However, there was no significant difference in rates of decline in FEV(1) between patients treated with IM progesterone and untreated patients (1.9 +/- 0.6% predicted vs 0.8 +/- 0.5% predicted, respectively; p = 0.520), and patients treated with po progesterone and untreated patients (3.2 +/- 0.8% predicted vs 0.8 +/- 0.5% predicted, respectively; p = 0.064). After adjusting for initial Dlco, rates of decline in Dlco were significantly higher in patients treated with po progesterone (3.6 +/- 0.7% predicted, p = 0.002) and IM progesterone (2.8 +/- 0.5% predicted, p = 0.022) than in untreated patients (1.6 +/- 0.6% predicted).

CONCLUSIONS

Within the limitations of a retrospective study, our data suggest that progesterone therapy does not slow the decline in lung function in LAM.

A patient with TSC1 germline mutation whose clinical phenotype was limited to lymphangioleiomyomatosis

BACKGROUND

Lymphangioleiomyomatosis (LAM) can occur as in isolated form (sporadic LAM) or as a pulmonary manifestation of tuberous sclerosis complex (TSC) (TSC-associated LAM). Recent studies, however, revealed that both forms of LAM are genetically related but that sporadic LAM is a distinct clinical entity caused by somatic mutations of TSC2 (not TSC1) rather than a forme fruste of TSC carrying either of the TSC1 or TSC2 germline mutations.

METHOD

Case presentation and in-depth molecular and histopathological examinations. A 34-year-old Japanese woman was diagnosed as having pulmonary lymphangioleiomyomatosis (LAM) when bilateral pneumothoraces were surgically treated in 1992. Although slowly progressive renal disfunction was observed due to bilateral multiple renal cysts during the past 4 years, she had no other clinical features of TSC and was diagnosed as having sporadic LAM with multiple renal cysts of undetermined aetiology. Her subsequent clinical course was complicated by an endobrochial carcinoid tumour, which eventually resulted in her death in June 1999 due to massive haemoptysis.

RESULTS

Postmortem examination revealed the presence of LAM lesions in the lungs, mediastinal lymph nodes, kidneys and uterus. Diffuse renal LAM lesions are presumed to generate multiple renal cysts by constricting the nephron rather than epithelial hyperplasia obstructing lumina, which is analysis of the TSC genes demonstrated that she did not have TSC2/PKD1 contiguous gene syndrome but had a TSC1 germline mutation (Sato T et al. J Hum Genet 2002; 47: 20-8) that had occured de novo.

CONCLUSION

This patient therefore illustrates that clinical manifestations of TSC are sufficiently diverse as to allow a forme fruste of TSC that mimics sporadic LAM and that TSC1 mutation can cause multiple renal cysts resulting in renal failure.