Relation of pulmonary lymphangio-leiomyomatosis to use of the oral contraceptive pill and fertility in the UK: a national case control study

Lymphangioleiomyomatosis and pregnancy: a mini-review

Lymphangioleiomyomatosis(LAM) is a slow progressive, rare cystic lung disease in women of reproductive age, associated with infiltration of the lung by atypical smooth muscle like cells, leading to the cystic destruction of the lung parenchyma. As LAM exclusively affects women of childbearing age, it can arise or exacerbate during pregnancy. Many patients with LAM are discouraged from pregnancy, although there is not much objective evidence effect on fertility. Patients diagnosed with LAM during pregnancy experience worse outcomes, so the safety of pregnancy is a vexing problem. What was worse, treatment strategies are limited on the effects of LAM on pregnancy outcomes. Pregnancy could be considered in LAM patients. Successful delivery in women with LAM depends on the condition of the LAM, which is in turn dependent on obstetricians and respiratory physicians. In this review, we describe the epidemiology, pathogenesis, diagnosis, clinical features and the treatment strategies of LAM during pregnancy.

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.

Lymphangioleiomyomatosis: a clinical review

Lymphangioleiomyomatosis (LAM) is a diffuse cystic lung disease. There are two main types of LAM: sporadic, and LAM associated with the tuberous sclerosis complex (TSC), which is caused by mutations in the TSC1 and TSC2 genes. LAM is characterised by cystic lung disease resulting in progressive dyspnoea, renal angiomyolipomas and lymphatic complications. Pneumothorax occurs frequently (70%) and definitive management with pleurodesis is recommended as the risk of recurrence is high. Characteristic thin-walled cysts are seen on computed tomography and the presence of elevated serum levels of a vascular endothelial growth factor-D has good diagnostic specificity. Currently, no single clinical or serological factor has been shown to predict prognosis. However, over the past decade, significant advances in our understanding of the pathophysiology of LAM has led to improved recognition of this rare disease and identification of treatment options. Mechanistic target of rapamycin inhibitors slow the rate of lung function decline and can resolve chylous effusion and regress angiomyolipomas. Life expectancy in patients with LAM is favourable, with a mean transplant-free survival >20 years from the time of diagnosis. Continued advances in understanding the molecular basis of LAM will lead to improved therapeutic targets and the development of more robust prognostic indicators.

Educational aims

To illustrate the clinical features, common presentations and radiological features of LAMTo outline the diagnostic approach to LAM, including the role of VEGF-DTo review the current prognostic indicators in LAM, and outline the impact of lung function, hormonal status, VEGF-D and clinical presentation on outcomeTo inform clinicians on the management options for LAM both pharmacological and nonpharmacological.

Gender, Estrogen, and Obliterative Lesions in the Lung

Gender has been shown to impact the prevalence of several lung diseases such as cancer, asthma, chronic obstructive pulmonary disease, and pulmonary arterial hypertension (PAH). Controversy over the protective effects of estrogen on the cardiopulmonary system should be of no surprise as clinical trials of hormone replacement therapy have failed to show benefits observed in experimental models. Potential confounders to explain these inconsistent estrogenic effects include the dose, cellular context, and systemic versus local tissue levels of estrogen. Idiopathic PAH is disproportionately found to be up to 4 times more common in females than in males; however, estrogen levels cannot explain why males develop PAH sooner and have poorer survival. Since the sex steroid hormone 17β-estradiol is a mitogen, obliterative processes in the lung such as cell proliferation and migration may impact the growth of pulmonary tissue or vascular cells. We have reviewed evidence for biological differences of sex-specific lung obliterative lesions and highlighted cell context-specific effects of estrogen in the formation of vessel lumen-obliterating lesions. Based on this information, we provide a biological-based mechanism to explain the sex difference in PAH severity as well as propose a mechanism for the formation of obliterative vascular lesions by estrogens.

Primary abdominal lymphangioleiomyomatosis: report of a case

Lymphangioleiomyomatosis is an uncommon progressive disease characterized by hamartomatous smooth muscle proliferation of the airways within the lungs as well as the lymph nodes, lymphatics, and blood vessels of the lungs, mediastinum, and abdomen. The most common manifestations of lymphangioleiomyomatosis are pulmonary symptoms. Primary abdominal lymphangioleiomyomatosis without any pathological changes in the respiratory system is extremely unusual. We report a case of primary abdominal lymphangioleiomyomatosis located between the left hepatic and gastric antrum of a 29-year-old woman. The patient had no typical symptoms of lymphangioleiomyomatosis (dyspnea, pneumothorax) or abdominal pain. All physical examination findings were normal. Laboratory test results, including routine blood examination, liver and kidney function, tumor markers, blood coagulation function, and urine and stool examinations, were all normal. She found abdominal cyst in an annual medical examination by ultrasonography and confirmed by computed tomography. For a clear diagnosis, a laparoscopic abdominal mass resection was performed. The postoperative pathohistological examination findings allowed for the definitive diagnosis. This case report may advance the understanding of primary peritoneal lymphatic leiomyoma and reduce the number of mistakenly diagnosed patients.

Association of oestrogen-containing contraceptives with pulmonary lymphangioleiomyomatosis in women with tuberous sclerosis complex--findings from a survey

OBJECTIVES About 30-40% of women with tuberous sclerosis complex (TSC) develop pulmonary lymphangioleiomyomatosis (LAM). Oestrogen seems to be involved in LAM pathogenesis and oestrogen-containing contraception should be avoided in women with known LAM. However, there is very little data on the use of contraceptives in TSC patients. METHODS We conducted a survey on the use of contraception and disease characteristics. The questionnaire was forwarded to all adult female TSC patients listed in the database of a German patient organisation. RESULTS Data from 39 such patients could be analysed. Of these, 15 were diagnosed with LAM. Twenty-five patients (65%) confirmed current or past use of oestrogen-containing contraceptives. We found a suggestive correlation between the history of oestrogen-containing contraception, and LAM (Odds ratio: 6.500; 95% confidence interval: 1.199-35.230). However, oestrogen use was not associated with LAM complications. CONCLUSIONS Based on our findings, oestrogen-containing contraceptives should be resorted to by these patients only with great caution, and avoided whenever possible.

Uterine-specific loss of Tsc2 leads to myometrial tumors in both the uterus and lungs

Lymphangioleiomyomatosis (LAM) is a rare disease characterized by proliferation of abnormal smooth-muscle cells in the lungs, leading to functional loss and sometimes lung transplantation. Although the origin of LAM cells is unknown, several features of LAM provide clues. First, LAM cells contain inactivating mutations in genes encoding Tsc1 or Tsc2, proteins that limit mTORC1 activity. Second, LAM tumors recur after lung transplantation, suggesting a metastatic pathogenesis. Third, LAM is found almost exclusively in women. Finally, LAM shares features with uterine leiomyomas, benign tumors of myometrial cells. From these observations, we proposed that LAM cells might originate from uterine leiomyomas containing Tsc mutations. To test our hypothesis, and to develop mouse models for leiomyoma and LAM, we targeted Tsc2 deletion primarily in uterine cells. In fact, nearly 100% of uteri from uterine-specific Tsc2 knockout mice developed myometrial proliferation and uterine leiomyomas by 12 and 24 weeks, respectively. Myometrial proliferation and mTORC1/S6 activity were abrogated by the mTORC1 inhibitor rapamycin or by elimination of sex steroid production through ovariectomy or aromatase inhibition. In ovariectomized Tsc2 null mice, mTORC1/S6 activity and myometrial growth were restored by estrogen but not progesterone. Thus, even without Tsc2, estrogen appears to be required for myometrial mTORC1/S6 signaling and proliferation. Finally, we found Tsc2 null myometrial tumors in lungs of older Tsc2 uterine-specific knockout females, suggesting that lung LAM-like myometrial lesions may indeed originate from the uterus. This mouse model may improve our understanding of LAM and leiomyomas and might lead to novel therapeutic strategies for both diseases.

Targeted approaches toward understanding and treating pulmonary lymphangioleiomyomatosis (LAM)

Pulmonary lymphangioleiomyomatosis (LAM) is a rare disease found almost exclusively in women that is characterized by neoplastic growth of atypical smooth muscle-like cells in the lung, destruction of lung parenchyma, and obstruction of lymphatics. These processes lead to the formation of lung cysts, rupture of which results in spontaneous pneumothorax. Progression of LAM often results in loss of pulmonary function and death. LAM affects predominantly women of childbearing age and is exacerbated by pregnancy. The only proven treatment for LAM is lung transplantation, and even then LAM cells will often return to the transplanted lung. However, methodical and targeted approaches toward understanding LAM pathophysiology have led to the discovery of new potential therapeutic avenues. For example, the mutational inactivation of tumor suppressor complex genes tuberous sclerosis complex 1 or tuberous sclerosis complex 2 has been shown to be present in lung LAM cells. These mutations occur sporadically or in association with inherited hamartoma syndrome tuberous sclerosis (TSC). Since TSC genes function as negative regulators of the mammalian target of rapamycin, a major controller of cell growth, metabolism, and survival, rapamycin analogs have recently been used to treat LAM patients with promising results. Similarly, studies focusing on the importance of estrogen in LAM progression have suggested that anti-estrogen therapy might prove to be an alternative means of treating LAM. This minireview summarizes recent progress in understanding LAM pathophysiology, including the latest preclinical and clinical studies, and insights regarding the role of hormones in LAM.

Infiltrative lung diseases in pregnancy

Pregnancy may affect the diagnosis, management, and outcome of infiltrative lung disease (ILD). Conversely, ILD may affect pregnancy. ILD may occur as a result of drugs administered commonly or specifically during pregnancy. Most ILDs predominate in patients older than 40 years and are thus rare in pregnant women. During pregnancy ILD may arise de novo and preexisting ILD may be exacerbated or significantly worsened. Some ILDs generally do not alter the management of pregnancy, labor, or delivery. Preexisting ILD no longer contraindicates pregnancy systematically, but thorough evaluation of ILD before pregnancy is required to identify potential contraindications and adapt monitoring.

Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare disease that mainly affects women, particularly at fertile age. It is sporadic or associated with tuberous sclerosis complex. It is characterised by an abnormal proliferation of immature smooth muscle cells (SMC), which grow aberrantly in the airway, parenchyma, lymphatics and pulmonary blood vessels and which can gradually lead to respiratory failure. It affects several systems, affecting the lymphatic ganglia and causing abdominal tumours. Given its very low prevalence, a difficult to establish early diagnosis, absence of curative treatment and the difficulty in obtaining information, places LAM under the heading of the so-called Rare Diseases. There is a growing interest in the study of this disease which has led to the setting up of patient registers and an exponential growth in LAM research, both at a clinical level and cellular level.

Lymphangioleiomyomatosis (LAM): molecular insights lead to targeted therapies

LAM is a rare lung disease, found primarily in women of childbearing age, characterized by cystic lung destruction and abdominal tumors (e.g., renal angiomyolipoma, lymphangioleiomyoma). The disease results from proliferation of a neoplastic cell, termed the LAM cell, which has mutations in either of the tuberous sclerosis complex (TSC) 1 or TSC2 genes. Molecular phenotyping of LAM patients resulted in the identification of therapeutic targets for drug trials. Loss of TSC gene function leads to activation of mammalian target of rapamycin (mTOR), and thereby, effects on cell size and number. The involvement of mTOR in LAM pathogenesis is the basis for initiation of therapeutic trials of mTOR inhibitors (e.g., sirolimus). Occurrence of LAM essentially entirely in women is consistent with the hypothesis that anti-estrogen agents might prevent disease progression (e.g., gonadotropin-releasing hormone analogues). Levels of urinary matrix metalloproteinases (MMPs) were elevated in LAM patients, and MMPs were found in LAM lung nodules. In part because of these observations, effects of doxycycline, an anti-MMP, and anti-angiogenic agent, are under investigation. The metastatic properties of LAM cells offer additional potential for targets. Thus, insights into the molecular and biological properties of LAM cells and molecular phenotyping of patients with LAM have led to clinical trials of targeted therapies. Funded by the Intramural Research Program, NIH/NHLBI.

Association of retroperitoneal lymphangioleiomyomatosis with endosalpingiosis: a case report

Lymphangioleiomyomatosis is a rare disorder of unknown origin that usually presents pulmonary symptoms. Retroperitoneal lymphangioleiomyomatosis without lung involvement has rarely been reported. We present a 38-year-old woman, the fourth case reported of retroperitoneal lymphangioleiomyomatosis with endosalpingiosis in the literature.

Pregnancy experiences among women with lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare lung disease affecting women. Following case reports that pregnancy exacerbates LAM, patients are frequently advised to avoid pregnancy. Our objective was to determine pregnancy and health outcomes in LAM to provide better evidence with which to council patients contemplating pregnancy. We surveyed 328 women with LAM regarding pregnancy outcomes, pulmonary function, subjective and psychological functioning, quality of life, dyspnoea and fatigue. Amongst childless women the main reason not to attempt pregnancy was based on concerns about potential effects of pregnancy on LAM. Almost two thirds of patients had been pregnant, the majority before LAM was diagnosed, in whom pregnancy outcome was generally favourable. Women diagnosed with LAM (n=15) during pregnancy had high rates of pneumothorax (67%), miscarriage (7%) and premature birth (47%). The group diagnosed with LAM before or during pregnancy (n=12) had lower mean FEV(1), FVC and DLCO after pregnancy compared with those diagnosed following pregnancy or never pregnant. There were no differences in subjective or psychological functioning, quality of life, dyspnoea or fatigue scores between groups. In newly diagnosed LAM patients there was a high incidence of premature birth and pneumothorax. These adverse outcomes may be a marker of aggressive LAM.

Lymphangioleiomyomatosis: A review

Lymphangioleiomyomatosis (LAM) is a rare disease, of unknown etiology, affecting women almost exclusively. Microscopically, LAM consists of a diffuse proliferation of smooth muscle cells. LAM can occur without evidence of other disease (sporadic LAM) or in conjunction with tuberous sclerosis complex (TSC). TSC is an autosomal dominant tumor suppressor gene syndrome characterized by seizures, mental retardation, and tumors in the brain, heart, skin, and kidney. LAM commonly presents with progressive breathlessness or with recurrent pneumothorax, chylothorax, or sudden abdominal hemorrhage. Computed tomography (CT) scans show numerous thin-walled cysts throughout the lungs, abdominal angiomyolipomas, and lymphangioleiomyomas. No effective treatment currently exists for this progressive disorder. The prevalence of lymphangioleiomyomatosis is probably underestimated based on its clinical latency and the absence of specific laboratory tests. With the utilization of international LAM data registries the "classical" picture of the disorder appears to be evolving as a larger number of patients are evaluated. An increased awareness of LAM and its common clinical presentation may advance the development of new therapeutic strategies and reduce the number of mistakenly diagnosed patients.

Activation of the estrogen receptor contributes to the progression of pulmonary lymphangioleiomyomatosis via matrix metalloproteinase-induced cell invasiveness

CONTEXT

The role of estrogens in the pathogenesis of lymphangioleiomyomatosis (LAM), an aggressive and destructive, eventually fatal lung disease of women, is poorly understood.

OBJECTIVE

The study was conducted to test the hypothesis that the lung disease in LAM is estrogen mediated and to determine whether estrogens contribute to the invasiveness of LAM.

DESIGN

In vitro cell culture of spindle-shaped LAM cells (LAMD-SM) were isolated and propagated from affected lungs. Estrogen receptor (ER)-alpha and ERbeta analyses were conducted by RT-PCR. ERalpha and ERbeta, tissue inhibitor of metalloproteinase-2, and matrix metalloproteinases (MMP)-2 had Western blot analysis for protein assessment. Activity assays were performed for MT1-MMP, MMP-2, and tissue inhibitor of metalloproteinase-2. Assessment of MMP-2 promoter function was done via transfection assays. Cell invasion chambers were used to determine and quantitate cell invasiveness.

SETTING

The study was conducted at an academic medical center.

PATIENTS

Tissue and cells were obtained from patients as outlined in approved institution review board protocol (97/007).

INTERVENTION

LAMD-SM cells were treated with a specific MMP-2 antibody or a nonspecific inhibitor, doxycycline.

MAIN OUTCOME MEASURES

Activity of MMP-2 and invasiveness of LAMD-SM cells were measured.

RESULTS

LAMD-SM cells express functional ERs (ERalpha and ERbeta), which undergo rapid intracellular turnover in their unbound state. 17beta-estradiol (E(2)) enhances the transcriptional ER activity. E(2)-induced ER activation increases synthesis and activity of MMP-2 through posttranscriptional mechanisms in LAMD-SM. The E(2)/ER-mediated increase of MMP-2 promotes LAMD-SM invasiveness, in assays in vitro, which can be inhibited by specific antibodies against MMP-2 or doxycycline, an inhibitor of MMPs.

CONCLUSION

The invasion and destruction of lung parenchyma in LAM is, at least partially, an estrogen-MMP-driven process, which has major implications for therapeutic interventions.

Lymphangioleiomyomatosis and tuberous sclerosis complex

Lymphangioleiomyomatosis (LAM) is a rare multisystemic disease of women of child-bearing age and affects mainly the lungs, promoting cystic destruction of lung parenchyma or leading to abdominal tumor formation (e.g., angiomyolipomas, lymphangioleiomyomas). LAM can arise sporadically or in association with tuberous sclerosis complex (TSC), an autosomal inherited syndrome characterized by hamartoma-like tumor growth and pathologic features that are distinct from manifestations of pulmonary LAM. A substantial body of evidence has now been gathered suggesting that the two diseases share a common genetic origin. TSC is caused by mutations in two genes, TSC1 on chromosome 9q34 and TSC2 on 16p13. Both of these genes are tumor suppressor genes encoding hamartin (TSC1) and tuberin (TSC2). Sporadic LAM is correlated with a mutation in the TSC2 gene and tuberin appears to play a central role in the pathogenesis of the disease. A TSC2 loss or mutation leads to disruption of the tuberin-hamartin heteromer and dysregulation of S6K1 activation leading to aberrant cell proliferation seen in LAM disease. The extremely diverse clinical and radiologic features of the disease and the complex therapeutic approach are reviewed in detail. Although new therapeutic agents have been tested, to date no effective treatment has been proposed and the prognosis of patients with LAM remains poor. As long as newer therapeutic agents do not change this picture, lung transplantation remains the last hope for patients with respiratory failure at the advanced stage of the disease.

Effect of a gonadotrophin-releasing hormone analogue on lung function in lymphangioleiomyomatosis

BACKGROUND

Lymphangioleiomyomatosis (LAM), a multisystem disease occurring primarily in women, is characterized by cystic lung destruction, and kidney and lymphatic tumors, caused by the proliferation of abnormal-appearing cells (ie, LAM cells) with a smooth muscle cell phenotype that express melanoma antigens and are capable of metastasizing. Estrogen receptors are present in LAM cells, and this finding, along with reports of disease progression during pregnancy or following exogenous estrogen administration, suggest the involvement of estrogens in the pathogenesis of LAM. Consequently, antiestrogen therapies have been employed in treatment. The goal of this prospective study was to evaluate the efficacy of triptorelin, a gonadotrophin-releasing hormone analogue, in 11 premenopausal women with LAM.

METHODS

Patients were evaluated at baseline and every 3 to 6 months thereafter, for a total of 36 months. Hormonal assays, pulmonary function tests, 6-min walk tests, high-resolution CT scans of the chest, and bone mineral density studies were performed.

RESULTS

Gonadal suppression was achieved in all patients. Overall, a significant decline in lung function was observed; two patients underwent lung transplantation 1 year after study enrollment, and another patient was lost to follow-up. Treatment with triptorelin was associated with a decline in bone mineral density.

CONCLUSIONS

Triptorelin appears not to prevent a decline in lung function in patients with LAM. Its use, however, may be associated with the loss of bone mineral density.

[Pulmonary lymphangioleiomyomatosis with or without tuberous sclerosis]

INTRODUCTION

Pulmonary lymphangioleiomyomatosis (LAM) is a rare disease affecting young women and presenting with recurrent pneumothorax.

BACKGROUND

Other lesions such as chylothorax or renal angiomyolipoma may suggest the diagnosis. The condition is related to a proliferation of abnormal smooth muscle cells staining for the monoclonal antibody HMB45. LAM can appear sporadically or be associated with tuberous sclerosis with abnormalities of the TSC2 suppressor gene. High resolution thoracic CT scanning shows bilateral, thin walled pulmonary cysts. Pulmonary function tests reveal bronchial obstruction and over-inflation with a reduced DLCO being the earliest abnormality.

VIEWPOINT

Although there are non-progressive forms, LAM usually leads to chronic respiratory insufficiency within a few, or ten or so years. In the absence of a controlled clinical trial hormone therapy has not been shown to be effective. Lung transplantation is the last therapeutic resort; recurrences in the transplanted lung have been occasionally reported.

CONCLUSIONS

Analysis of the molecular mechanisms induced by mutations of the TSC2 suppressor gene and the demonstration of the migratory properties of smooth muscle cells, whose origin may be extra-thoracic, reveal new specific antiproliferative therapeutic options.

Case 116: Lymphangioleiomyomatosis

A 49-year-old premenopausal woman presented with acute onset of lower abdominal pain. Physical examination revealed her abdomen was distended and nontender. Her white blood cell count and serum markers for ovarian cancer were normal (alpha-fetoprotein level, 1.6 microg/L; Ca-125 level, 15 U/mL; beta-human chorionic gonadotrophin level < 2 IU/mL). She had no important medical history; in particular, she had no history of malignancy. She denied having any chest symptoms; in particular, she denied experiencing chest pain, cough, or dyspnea. She had stopped smoking at the age of 40 years after having smoked for a total of 20 pack-years. A computed tomographic (CT) examination of the abdomen and pelvis was performed. Helical CT was performed with 150 mL of intravenous contrast material (iohexol, Omnipaque; Amersham Healthcare, Cork, Ireland) and 750 mL of oral contrast material (diatrizoate sodium, Hypaque; Amersham Health, Princeton, NJ). CT sections were 5 mm thick and were acquired from the top of the diaphragm through the ischial tuberosities with a rotation time of 13.5 seconds per rotation and use of a LightSpeed 16 CT scanner (GE Medical Systems, Milwaukee, Wis).

Respiratory physiologic changes in pregnancy

In summary, the major physiologic changes that occur in pregnancy are the increased minute ventilation, which is caused by increased respiratory center sensitivity and drive; a compensated respiratory alkalosis; and a low expiratory reserve volume. The vital capacity and measures of forced expiration are well preserved. Patients who have many lung diseases tolerate pregnancy well, with the exception of those who have pulmonary hypertension or chronic respiratory insufficiency from parenchymal or neuromuscular disease.

The diverse clinical manifestations of tuberous sclerosis complex: a review

Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem neurocutaneous disorder. TSC results in hamartomatous lesions primarily involving the skin, central nervous system, kidneys, eyes, heart, and lungs. The clinical findings and severity of TSC are highly variable. Recent advances in our understanding of the complexities of the TSC1 and TSC2 genes are making genotype-phenotype correlations possible. While managing seizures, cognitive dysfunction, and behavioral abnormalities are the primary responsibility of the neurologist, familiarity with all aspects of this disease helps provide better comprehensive care for affected individuals.

Linfangioleiomiomatose: A propósito de um caso clínico

Lymphangioleiomyomatosis (LAM) is a rare disease of unknown etiology affecting woman, primarily in their reproductive years. It is characterized by non-neoplasic proliferation of atypical smooth muscle cells that may lead to airway, lymphatic and blood vessel obstruction over time.A nine-year followed-up case of LAM is described,which presents with some unusual details as worsening haemoptysis in the setting of pregnancy and absence of cough or pneumothorax along the course of the disease. Neither haemoptysis nor gradual pulmonary function deterioration seemed to be influenced by hormone therapy. A brief re-view of the disease is then presented.

Pregnancy and lymphangioleiomyomatosis: anaesthetic management

Lymphangioleiomyomatosis is a rare, progressive cystic pulmonary disease related to tuberous sclerosis complex, affecting almost exclusively females of childbearing age. Progression of the disease is variable but may lead to terminal respiratory failure. As the disease may be oestrogen-dependent, it can arise de novo in pregnancy or established disease may undergo exacerbation. We report on the successful labour and delivery of such a patient and present the results of an internet survey of 30 pregnancies in 15 patients worldwide with lymphangioleiomyomatosis conducted by our patient before delivery.

Linfangioleiomiomatose pulmonar

Linfangioleiomiomatose pulmonar (LAM) é uma doença rara, de etiologia desconhecida, que basicamente afeta mulheres jovens no período fértil de sua vida. Clinicamente, manifesta-se através de dispnéia progressiva, pneumotórax de repetição, tosse seca e, menos freqüentemente, por quilotórax e escarros hemoptóicos. Essas alterações surgem devido à proliferação anormal de células de músculo liso no parênquima pulmonar, linfonodos e em outros tecidos. Mais recentemente, estudos citogenéticos verificaram a presença de mutações do gene TSC-2 em células de angiomiolipoma renal e linfonodos abdominais de pacientes com LAM, indicando uma possível origem para as lesões hamartomatosas da doença. Radiologicamente, caracteriza-se pela presença de infiltrado intersticial reticulonodular e sinais de hiperinsuflação ao radiografia de tórax. Na tomografia computadorizada de alta resolução, cistos de paredes finas, localizados centralmente, são visibilizados por todo o parênquima do pulmão. O ultrassom e a tomografia de abdome podem revelar angiomiolipomas renais e linfonodomegalias retroperitoneais. Meningeomas também podem estar associados, porém a sua presença deve sempre levar à pesquisa de esclerose tuberosa. Funcionalmente, a doença caracteriza-se por um distúrbio ventilatório obstrutivo, de caráter progressivo, com hiperinsuflação pulmonar e diminuição da difusão de monóxido de carbono. Apesar da ausência de comprovação quanto à eficácia, o principal tratamento utilizado ainda é o anti-estrogênico e constitui-se de oofarectomia, progesterona contínua, tamoxifeno e análogos de GnRH. Além desse, a realização de transplantes pulmonares tem elevado para além de dez anos a sobrevida média das pacientes.

Lymphangioleiomyomatosis: a case-control study of perinatal and early life events

BACKGROUND

Lymphangioleiomyomatosis (LAM), a rare disease affecting women, is caused by somatic mutations in the tuberous sclerosis complex genes.

METHODS

A case-control questionnaire study was carried out examining parental and family history, prenatal events, and early life events to try to shed light on the aetiology of the condition. Forty five patients identified from a national LAM register completed a questionnaire and 31 were compared with 117 age and sex matched control subjects using conditional logistic regression.

RESULTS

No differences were found in perinatal events, childhood infections, and parental or family history, except that patients were more likely to be an only child (odds ratio (OR) 4.3 (95% confidence interval (CI), 1.5 to 11.8)) and have a relative with uterine fibroids (OR 4.2 (1.4 to 13)). Patients with LAM had had fewer pregnancies and fewer children but no differences in miscarriage rates. A non-matched analysis using all 45 cases and 117 controls gave similar results.

CONCLUSIONS

No features in the family history, perinatal events, or early life events were detected that were associated with having LAM. Being more likely to be an only child and having an increased family history of uterine fibroids may, if confirmed, indicate some differences in reproductive function within the families of affected individuals.

Lymphangioleiomyomatosis initially presenting with abdominal pain: a case report

Lymphangioleiomyomatosis (LAM) is a rare idiopathic disease characterized by hamartomatous smooth muscle proliferation of the lymph node, lymphatics, blood vessels as well as airways within the lungs, mediastinum and abdomen. It exclusively affects women during the reproductive period. Though extrapulmonary manifestations have been reported, the initial presentation of LAM as abdominal pain is extremely rare. To our knowledge, there are only three cases with LAM presenting first with abdominal symptoms so far [Chest 106 (1994) 267; Eur J Radiol 14 (1992) 192; Eur J Surg 157 (1991) 36]. We describe a case of LAM suffering from abdominal pain followed by pulmonary symptoms and the diagnosis was not made until pathohistological examination.

Pulmonary lymphangioleiomyomatosis (LAM): examining oral contraceptive pills and the onset of disease

BACKGROUND

Lymphangioleiomyomatosis (LAM) is a rare pulmonary disease of women of unknown etiology. Diffuse cystic changes associated with multifocal clusters of smooth muscle-like cells (LAM cells) replace normal lung parenchyma, leading to progressive loss of lung function. Reports of exacerbations of LAM with the use of exogenous estrogens and during pregnancy suggest an association between hormones and clinical deterioration.

OBJECTIVES

To conduct the largest case series to date in order to characterize the demographics of a living cohort of patients with LAM. To evaluate the effect of oral contraceptive pill (OCPs) use on the age at onset of symptoms in a large population of women with LAM.

METHODS

The study population was drawn from the University of Miami (UM) LAM database consisting of 91 living women previously diagnosed with LAM by a physician. A self-administered questionnaire was mailed to the participants.

RESULTS

The final response rate was 91.2% (83 of 91), and the study participants were 96.4% white, 1.2% Asian, 1.2% African American, and 1.2% American Indian; 68.4% identified their ethnicity as European and 14.5% as Jewish. Of the women surveyed, 73 were still menstruating at the time of LAM diagnosis. Among these women, the rate of use of OCPs was approximately 27%, similar to the rate in the general population. There was a significant difference between the age at onset of symptoms in women using OCPs vs. women not using OCPs (29.2 +/- 4.7 vs. 32.9 +/- 8.0, p = 0.0397).

CONCLUSIONS

The present study suggests that OCPs may serve as catalysts to promote an earlier occurrence of LAM.

Giles F. Filley Lecture. Genetics and gene expression in lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a disease of unknown etiology that is characterized by the proliferation of abnormal smooth muscle cells (LAM cells) in the lung, which leads to cystic parenchymal destruction and progressive respiratory failure. Recent evidence suggests that the proliferative and invasive nature of LAM cells may be due, in part, to somatic mutations in the TSC2 gene, which has been implicated in the pathogenesis of tuberous sclerosis complex. Here, we describe the clinical and molecular characteristics of LAM, as well as the efforts now under way to understand the genetic and biochemical factors that lead to progressive pulmonary destruction and, ultimately, to lung transplantation or death.

Mutational and radiographic analysis of pulmonary disease consistent with lymphangioleiomyomatosis and micronodular pneumocyte hyperplasia in women with tuberous sclerosis

Lymphangioleiomyomatosis (LAM) and multifocal micronodular pneumocyte hyperplasia (MMPH) produce cystic and nodular disease, respectively, in the lungs of patients with tuberous sclerosis. The objective of this study was to prospectively characterize the prevalence, clinical presentation, and genetic basis of lung disease in TSC. We performed genotyping and computerized tomographic (CT) scanning of the chest on 23 asymptomatic women with tuberous sclerosis complex (TSC). Cystic pulmonary parenchymal changes consistent with LAM were found in nine patients (39%). These patients tended to be older than cyst-negative patients (31.9 +/- 7.6 yr versus 24.8 +/- 11.6 yr, p = 0.09). There was no correlation between presence of cysts and tobacco use, age at menarche, history of pregnancy, or estrogen-containing medications. Three of the cyst-positive patients had a prior history of pneumothorax. Pulmonary function studies revealed evidence of gas trapping but normal spirometric indices in the cyst-positive group. All nine cyst-positive patients had angiomyolipomas (AML), which were larger (p < 0.05) and more frequently required intervention (p = 0.08) than cyst-negative patients (8 of 14 with AMLs, p < 0.05). Ten patients (43%) had pulmonary parenchymal nodules. Pulmonary nodules were more common in women with cysts (78% versus 21%, p < 0.05), and 52% of all patients had either cystic or nodular changes. TSC2 mutations were identified in all cyst-positive patients who were tested (n = 8), whereas both TSC1 and TSC2 mutations were found in patients with nodular disease. Correlation of the mutational and radiographic data revealed one pair of sisters who were discordant for cystic disease, two mother- daughter pairs who were discordant for nodular disease, and no clear association between cyst development and a specific mutational type. This prospective analysis demonstrates that cystic and nodular pulmonary changes consistent with LAM and MMPH are common in women with TSC.

Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM), a rare disorder of unknown cause that occurs almost exclusively in women of childbearing years, is characterized microscopically by abnormal smooth muscle proliferation in the lung, lymphatics, and mediastinal, abdominal and lower cervical lymph nodes. LAM is associated with progressive dyspnea, recurrent pneumothoraces, chylous effusions, abdominal tumors (angiomyolipoma), and chylous ascites. Because of the predilection of this disease for young women, therapies to date have mainly involved hormonal manipulation. Although the efficacy of these therapies has not been established, the clinical course is more favorable in recent studies compared with earlier reports.

Clinical experience of lymphangioleiomyomatosis in the UK

BACKGROUND

Lymphangioleiomyomatosis is a rare lung disease that affects only women. No controlled trials of management have been performed and, until such data are available, management must be based on clinical experience. This study provides data on the natural history of lymphangioleiomyomatosis in the UK and compares this with experience from other centres.

METHODS

We tried to identify all cases of lymphangioleiomyomatosis in the UK over a five year period by contacting all chest physicians. Cases were confirmed by lung biopsy or history and high resolution computed tomographic (CT) scanning. Details of disease and management were obtained from hospital notes.

RESULTS

The 50 patients who fitted the diagnostic criteria for lymphangioleiomyomatosis had a median age at onset of 35 years (range 22-50). Five presented when postmenopausal (four taking hormone replacement therapy). Pneumothorax and dyspnoea were the most common presenting features. Extrapulmonary presentations included renal angiomyolipomas (3) and lymphangiomyomas (2). Only half the patients were assessed for renal angiomyolipoma and six were identified. Thirty patients had had one or more pneumothoraces, of which two thirds recurred if treated conservatively. Chylous effusions occurred in 11 patients, five requiring surgery. Pregnancy was uncommon once the diagnosis was made (n=7), but was associated with an increase in complications. Half the patients were taking a beta agonist and many showed a bronchodilator response in the laboratory. Thirty six patients had received hormone treatment.

CONCLUSIONS

Our UK five year period prevalence was one per 1.1 million population. Since prophylactic interventions are sometimes indicated for renal angiomyolipoma, these data suggest that screening for angiomyolipoma, ideally by CT scanning, may be underused. Patients need to be aware of the increase in complications associated with pregnancy. Recurrence rate of pneumothorax was high in those not treated surgically. Hormone treatment was used variably and controlled trials are needed to determine their role and the optimum duration and dose.

Pulmonary lymphangioleiomyomatosis. A study of 69 patients. Groupe d'Etudes et de Recherche sur les Maladies "Orphelines" Pulmonaires (GERM"O"P)

Pulmonary lymphangioleiomyomatosis (LAM) is a rare disorder of unknown cause characterized by peribronchial, perivascular, and perilymphatic proliferation of abnormal smooth muscle cells leading to cystic lesions. The hypothesis of hormonal dependence and the effectiveness of hormonal therapy have not yet been demonstrated conclusively, and the prevalence of extrathoracic manifestations and the survival of patients with LAM are somewhat contradictory. A multicentric retrospective study was conducted in an attempt to describe better the initial features, the diagnostic procedures, the associated lesions, and, above all, the management and course of LAM in a large homogeneous series of 69 stringently selected patients, with a majority of cases diagnosed since 1990. The aim of the study, based on a review of the literature, also was to provide a comprehensive view of this uncommon disease. The clinical features were in keeping with previous studies, but we found that exertional dyspnea and pneumothorax were the most common features, and chylous involvement was less frequent. LAM was diagnosed after menopause in about 10% of cases. The onset of LAM occurred during pregnancy in 20% of cases, and a clear exacerbation of LAM was observed in 14% of cases during pregnancy. Pulmonary LAM was diagnosed on lung histopathology in 83% of cases, but renal angiomyolipoma, observed in 32% of our patients, may be a useful diagnostic criterion when associated with typical multiple cysts on chest CT scan or with chylous effusion. Chest CT scan was more informative than chest X-ray (normal in 9% of cases), and may be indicated in spontaneous pneumothorax or renal angiomyolipoma in women of childbearing age. About 40% of the patients had a normal initial spirometry, while an obstructive ventilatory defect (44%), a restrictive ventilatory defect (23%), was observed in other patients. Initial diffusing capacity for carbon monoxide was frequently decreased (82%). Hormonal therapy was administered in 57 patients, but a clear > or = 15% improvement of FEV1 was observed in only 4 evaluable patients, treated with tamoxifen and progestogens (n = 2), progestogen (n = 1), and oophorectomy (n = 1). Probably 1 of the most urgent needs for clinical research in LAM is to test the currently available hormonal treatments in the context of international multicenter prospective controlled studies. Pleurodesis was performed in 40 patients. Lung transplantation was performed in 13 patients, 7.8 +/- 5.2 years after onset of LAM, in whom the mean FEV1 was 0.57 +/- 0.15 L. After a follow-up of 2.3 +/- 2.2 years, 9 patients were alive. Mean follow-up from onset of disease to either death or closing date was 8.2 +/- 6.3 years. Overall survival was better than usually reported in LAM, and Kaplan-Meier plot showed survival probabilities of 91% after 5 years, 79% after 10 years, and 71% after 15 years of disease duration.

[Pulmonary lymphangioleiomyomatosis: an often fortuitous diagnosis. A case report]

INTRODUCTION

Lymphangioleiomyomatosis is an uncommon disorder of unknown origin, which exclusively occurs in women of reproductive age. The condition is characterized by proliferation of immature smooth muscle cells throughout the lungs, i.e., in the peribronchial, perilymphatic, and perivascular areas. This results in obliteration of the respiratory tract and in the development of cysts. Lymphangioleiomyomatosis has a poor prognosis due to both numerous lung complications and progression of the disease to respiratory failure.

EXEGESIS

We report the case of a patient in whom lymphangioleiomyomatosis was fortuitously diagnosed from chest CT scan, itself performed for the diagnosis of pulmonary embolism. This case is therefore of particular interest.

CONCLUSION

Our results suggest that the prevalence of lymphangioleiomyomatosis is probably underestimated due to its clinical latency and the absence of specific laboratory tests. Therefore, the development of non-invasive radiological methods should permit early diagnosis of the disease.

When to suspect and how to diagnose pulmonary lymphangioleiomyomatosis

The objective of this study was to present clinical and radiological data of eight women with histologically proven lymphangioleiomyomatosis (LAM) diagnosed between 1984 and 1994, and to suggest a diagnostic strategy when LAM is suspected. A review of case reports, including results of biopsies, lung function and radiological procedures was undertaken. The mean age of the women at start of symptoms was 36 years, and the mean age at time of diagnosis 42 years. The most frequent presenting complaint was dyspnea, either in conjunction with pneumothorax (3), chylothorax (2) or on exertion (2). All patients had airflow limitation and markedly reduced gas transfer. Five patients had 16 episodes of pneumothorax. In seven patients multiple cysts were observed on the surface of the lung during thoracotomy while computerized tomography (CT) scans revealed numerous cysts evenly distributed throughout the lung parenchyma. The procedures that confirmed the diagnosis included transbronchial lung biopsy (4), open lung biopsy (2), thoracoscopy (1), thoracotomy (3) and autopsy (1). Three specimens had to be revised before the histological diagnosis was confirmed. It was concluded that the important clues to a diagnosis of LAM are recurrent episodes of pneumothoraces in fertile women, progressive air-flow limitation, markedly reduced gas transfer and characteristic findings on thoracic CT scans. A specific request to the pathologist to stain lung tissue specimens for smooth muscle cells is mandatory.