Diagnosis of pulmonary lymphangioleiomyomatosis by HMB45 in surgically treated spontaneous pneumothorax

Sirolimus Suppresses Phosphorylation of Cofilin and Reduces Interstitial Septal Thickness in Sporadic Lymphangioleiomyomatosis

Sporadic lymphangioleiomyomatosis (S-LAM) is a rare lung disease characterized by the proliferation of smooth muscle-like LAM cells and progressive cystic destruction. Sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, has a proven efficacy in patients with LAM. However, the therapeutic mechanisms of sirolimus in LAM remain unclear. We aimed to evaluate sirolimus-related lung parenchymal changes and the potential effect in LAM cells and modulating pathological cystic destruction. Lung specimens were examined for histopathological changes by HMB45 staining and compared the LAM patients treated with and without sirolimus. We detected the overexpression of mTOR, HMB45, and phosphorylation of cofilin (p-cofilin) in LAM patients. Sirolimus showed efficacy in patients with LAM, who exhibited a reduced expression of mTOR and p-cofilin as well as reduced interstitial septal thickness. In addition, sirolimus suppresses mTOR and p-cofilin, thus suppressing the migration and proliferation of LAM cells isolated from the patient's lung tissue. This study demonstrates that interstitial septal thickness, as determined by histological structural analysis. Sirolimus effectively reduced the expression of p-cofilin and interstitial septal thickness, which may be a novel mechanism by sirolimus. Moreover, we develop a new method to isolate and culture the LAM cell, which can test the possibility of medication in vitro and impact this current study has on the LAM field. The development of approaches to interfere with mTOR-cofilin1-actin signaling may result in an option for S-LAM therapy.

A 34-Year-Old Woman from Brazil with Pulmonary Lymphangioleiomyomatosis Diagnosed by Raised Serum Vascular Endothelial Growth Factor-D (VEGF-D) Levels and Lung Cysts on Computed Tomography Imaging Presenting with COVID-19 Pneumonia

Patient: Female, 34-year-old

Final Diagnosis: COVID-19 • lymphangioleiomyomatosis

Symptoms: Dyspnea • fever • hypoxemia • myalgia

Medication: Sirolimus

Clinical Procedure: —

Specialty: Pulmonology

Lymphangioleiomyomatosis: A Case Report and Review of Clinical Features and Management

Pulmonary sporadic lymphangioleiomyomatosis (LAM) is a female-dominant disease associated with smooth muscle cell proliferation, which results in cystic lung disease presenting commonly with dyspnea and pneumothorax. This article aims to present a patient with the common clinical features and complications of LAM so as to aid in the efficient diagnosis and treatment of future patients. Limited options in the management of LAM make early diagnosis key, as management focuses on supportive care to slow the progressive decline of pulmonary function. Workup includes a diagnosis of exclusion with specific antibodies or titers such as anti-Sjögren's syndrome type A (anti-SSA) antibodies, anti-Sjögren's syndrome type B (anti-SSB) antibodies, angiotensin-converting enzyme (ACE) levels, alpha-1-antitrypsin levels, and vascular endothelial growth factor (VEGF) antibodies with definitive diagnosis limited to tissue confirmation. Here, we discuss a 39-year-old female with dyspnea and spontaneous pneumothorax, who was subsequently diagnosed with LAM during her hospitalization and managed outpatient with sirolimus therapy.

Immunotherapy for Lymphangioleiomyomatosis and Tuberous Sclerosis: Progress and Future Directions

Pulmonary lymphangioleiomyomatosis (LAM) is a rare genetic multisystem disease characterized by the nodular proliferation of smooth muscle-like LAM cells, progressive cystic changes of the lung, lymphatic abnormalities, and renal angiomyolipomas (AMLs). LAM can arise sporadically or in women with the autosomal dominant disorder, tuberous sclerosis complex (TSC), in which hamartomatous tumors of brain, heart, skin, kidney, and lung are found. LAM and TSC are caused by mutations in the TSC1 or TSC2 tumor suppressor genes leading to elevated mechanistic/mammalian target of rapamycin complex activity. Recent data indicate that T cells within LAM nodules and renal AMLs exhibit features of T-cell exhaustion, with coinhibitory receptor programmed cell death protein 1 (PD-1) expression on tumor-infiltrating T cells. Treatment of animal models of TSC and LAM with anti-PD-1 antibodies or with the combination of anti-PD-1 and anti-CTLA4 antibodies has led to remarkable results, suppressing TSC2-null tumor growth and inducing tumor rejection. Here we review our current knowledge about the potential for immunotherapy for the treatment of LAM and TSC and highlight critical unknowns and key next steps.

Genomic rearrangements in sporadic lymphangioleiomyomatosis: an evolving genetic story

Sporadic lymphangioleiomyomatosis is a progressive pulmonary cystic disease resulting from the infiltration of smooth muscle-like lymphangioleiomyomatosis cells into the lung. The migratory/metastasizing properties of the lymphangioleiomyomatosis cell together with the presence of somatic mutations, primarily in the tuberous sclerosis complex gene (TSC2), lead many to consider this a low-grade malignancy. As malignant tumors characteristically accumulate somatic structural variations, which have not been well studied in sporadic lymphangioleiomyomatosis, we utilized mate pair sequencing to define structural variations within laser capture microdissected enriched lymphangioleiomyomatosis cell populations from five sporadic lymphangioleiomyomatosis patients. Lymphangioleiomyomatosis cells were confirmed in each tissue by hematoxylin eosin stain review and by HMB-45 immunohistochemistry in four cases. A mutation panel demonstrated characteristic TSC2 driver mutations in three cases. Genomic profiles demonstrated normal diploid coverage across all chromosomes, with no aneuploidy or detectable gains/losses of whole chromosomal arms typical of neoplastic diseases. However, somatic rearrangements and smaller deletions were validated in the two cases which lacked TSC2 driver mutations. Most significantly, one of these sporadic lymphangioleiomyomatosis cases contained two different size deletions encompassing the entire TSC1 locus. The detection of a homozygous deletion of TSC1 driving a predicted case of sporadic lymphangioleiomyomatosis, consistent with the common two-hit TSC2 mutation model, has never been reported for sporadic lymphangioleiomyomatosis. However, while no evidence of the hereditary tuberous sclerosis complex disease was reported for this patient, the potential for mosaicism and sub-clinical phenotype cannot be ruled out. Nevertheless, this study demonstrates that somatic structural rearrangements are present in lymphangioleiomyomatosis disease and provides a novel method of genomic characterization of sporadic lymphangioleiomyomatosis cells, aiding in defining cases with no detected mutations by conventional methodologies. These structural rearrangements could represent additional pathogenic mechanisms in sporadic lymphangioleiomyomatosis disease, potentially affecting response to therapy and adding to the complex genetic story of this rare disease.

Minireview: Lymphangioleiomyomatosis (LAM): The "Other" Steroid-Sensitive Cancer

Lymphangioleiomyomatosis (LAM) is a devastating rare lung disease affecting primarily childbearing age women in which tumors consisting of abnormal smooth-muscle-like cells grow within the lungs and progressively lead to loss of pulmonary function. LAM cells metastasize to the lungs, predominantly through the lymphatics; however, the source of the LAM cell is still unknown. LAM cells contain inactivating mutations in genes encoding tuberous sclerosis 1 or 2, proteins that normally limit cell growth through suppression of mammalian target of rapamycin complex 1. As of today, sirolimus (an mammalian target of rapamycin complex 1 inhibitor) is the only treatment, available for LAM patients that is approved by the Food and Drug Administration; however, this drug and others in its class provide stabilization but not remission of LAM. One of the biggest problems in treating LAM is that both the origin of the LAM cells and the mechanism of the sexual dimorphism in LAM are still not understood. LAM cells express estrogen and progesterone receptors, and lung function declines during periods of high circulating estrogen levels. Moreover, numerous basic research studies find that estrogen is a key driving force in LAM cell proliferation, migration, and metastasis. In this review, we highlight recent insights regarding the role of steroid hormones in LAM and discuss possible explanations for the profound female sexual dimorphism of LAM.

Estrogen maintains myometrial tumors in a lymphangioleiomyomatosis model

Lymphangioleiomyomatosis (LAM) is a rare disease in women. Patients with LAM develop metastatic smooth-muscle cell adenomas within the lungs, resulting in reduced pulmonary function. LAM cells contain mutations in tuberous sclerosis genes (TSC1 or TSC2), leading to up-regulation of mTORC1 activity and elevated proliferation. The origin of LAM cells remains unknown; however, inactivation of Tsc2 gene in the mouse uterus resulted in myometrial tumors exhibiting LAM features, and approximately 50% of animals developed metastatic myometrial lung tumors. This suggests that LAM tumors might originate from the uterine myometrium, possibly explaining the overwhelming prevalence of LAM in female. Here, we demonstrate that mouse Tsc2-null myometrial tumors exhibit nearly all the features of LAM, including mTORC1/S6K activation, as well as expression of melanocytic markers and matrix metalloproteinases (MMPs). Estrogen ablation reduces S6K signaling and results in Tsc2-null myometrial tumor regression. Thus, even without TSC2, estradiol is required to maintain tumors and mTORC1/S6K signaling. Additionally, we find that MMP-2 and -9, as well as neutrophil elastase (NE), are overexpressed in Tsc2-null myometrial tumors in an estrogen-dependent fashion. In vivo fluorescent imaging using MMP- or NE-sensitive optical biomarkers confirms that protease activity is specific to myometrial tumors. Similar to LAM cells, uterine Tsc2-null myometrial cells also overexpress melanocytic markers in an estrogen-dependent fashion. Finally, we identify glycoprotein NMB (GPNMB) as a melanocytic marker up-regulated in Tsc2-null mouse uteri and human LAM samples. Our data highlight the potential importance of estradiol in LAM cells, suggesting that anti-estrogen therapy may be a treatment modality. Furthermore, proteases and GPNMB might be useful LAM biomarkers.

Endometrial stromal sarcomas: immunoprofile with emphasis on HMB45 reactivity

OBJECTIVES

We describe the morphologic and immunohistochemical features of 17 endometrial stromal neoplasms, 16 sarcomas, and one stromal nodule.

METHODS

We reviewed 35 cases interpreted as endometrial stromal neoplasms, but 17 high-grade endometrial stromal sarcomas (ESS) and one case of mixed endometrial sarcoma and leiomyosarcoma were excluded from the study. Data from the Surveillance Epidemiology and End Results program on low- and high-grade ESS for 1973 through 2003 were obtained.

RESULTS

One uterine primary ESS had collections of clear cells (20%), while a metastatic ESS contained predominantly clear cells (90%). CD10 (88.2%) and smooth muscle actin (70.5%) were the most common positive immunohistochemical markers. The latter marker was located in the cytoplasm in 47% of the ESS and in the nucleus in 23.5%, a previously unreported feature. HMB45 was detected in 23.5% of the ESS, which contrasts with the 2% reported by other authors.

CONCLUSIONS

The presence of clear cells and HMB45 reactivity does not justify the term perivascular epithelioid cell tumors for these neoplasms. Two of 17 patients with ESS died of metastatic disease. However, among 274 cases of ESS (all stages included) collected by the Surveillance Epidemiology and End Results Program of the National Cancer Institute during a 30-year period, the 10-year survival rate was 94%.

Efficacy of hormonal suppression in a patient with chyluria due to lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare lung disease affecting almost exclusively young women, characterised by abnormal proliferation of atypical smooth muscle cells. We describe a young woman presenting with chyluria secondary to the presence of a large retroperitoneal lymphangioleiomyoma. Immunohistochemical analysis revealed HMB45-negative LAM cells (HMB45 staining is absent only in rare cases) expressing low levels of estrogen receptors. Estrogen suppressive treatment with triptoreline, a synthetic analogue of Gn-RH, resulted in dramatic reduction of the retroperitoneal mass size. The role of estrogens in the pathogenesis of LAM remains poorly understood, and hormonal therapy is still debated, but this case suggests that at least in some LAM patients, possibly those with HMB45-negative disease and estrogen receptor expression, hormonal therapy may be effective in controlling the disease process.

β-Catenin is a useful adjunct immunohistochemical marker for the diagnosis of pulmonary lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare multisystem disease leading to cystic destruction of the lung parenchyma and is associated with abnormal smooth muscle proliferation affecting airways, lymphatics, and blood vessels. LAM occurs sporadically or in association with the tuberous sclerosis complex (TSC). Recent evidence demonstrates the role of aberrant β-catenin signaling in TSC. To further understand the pathogenesis of LAM and to examine the diagnostic usefulness of β-catenin, we examined protein expression in 28 pulmonary LAM cases and 10 cases of renal angiomyolipoma resected from patients with sporadic LAM. Immunohistochemical analysis was performed for established markers of LAM cells (HMB45, estrogen receptor [ER]-α, and progesterone receptor [PR]) and β-catenin. All LAM cases were positive for β-catenin and demonstrated high specificity with overall immunoreactivity superior to HMB45, ER-α, and PR. Similar expression was demonstrated in renal angiomyolipoma. Our results indicate that β-catenin is a useful marker of LAM and may be clinically useful in the diagnostic setting.

Pulmonary lymphangioleiomyomatosis: unusual manifestations of multiple large pulmonary nodules with retroperitoneal lymph node involvement mimicking metastatic malignancy

Pulmonary lymphangioleiomyomatosis (LAM) is a rare, idiopathic disorder that predominantly affects the lung parenchyma of women of childbearing age. While the characteristic radiographic finding of pulmonary LAM consists of multiple well-defined thin-walled cysts, we describe a very unusual case of pulmonary LAM with multiple bilateral large pulmonary nodules and retroperitoneal involvement mimicking metastatic malignancy. A 48-year-old woman who had never smoked with a history of bilateral pneumothorax presented with progressive exertional dyspnea and abdominal discomfort. Imaging studies revealed multiple enlarged retroperitoneal lymph nodes, ascites and bilateral multiple large pulmonary nodules ranging from 3 to 18 mm in diameter. Exploratory laparoscopic surgery for intra-abdominal lesions and video-assisted thoracoscopic wedge resection of lung nodules were carried out to rule out metastatic malignancy. Pathology showed benign looking smooth muscle cell proliferation and immunoreactivity for α-smooth muscle actin and HMB-45 in both specimens. After treatment with GnRH antagonist, the patient was well over a 6-month period without evidence of disease progression.

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).

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.

Difficulties in the diagnosis of rare immunological diseases manifesting with cystic lung disease and spontaneous pneumothorax: case reports

Pulmonary lymphangioleiomyomatosis (LAM) is a rare disease of an unknown cause affecting women of reproductive age and characterised by smooth muscle proliferation along lung lymphatic channels. Pneumothorax develops in up to 80% of patients with LAM and may be the presenting manifestation of the disease. Pneumothorax also precedes or complicates the clinical course of 25% of patients with Langerhans'-cell histiocytosis (LCH, histiocytosis X) pathologically characterised by involved tissue infiltration with large numbers of unusual Langerhans' cells, often organised as granulomas. A 41-year-old female patient was treated twice by simple tube drainage due to left pneumothorax in 1996. She was then diagnosed with chronic obstructive lung disease demonstrating with dyspnea, cough and wheeze. Abnormalities found in the high-resolution computed tomography (HRCT) scanning were characteristic of LAM with thin-walled parenchymal cysts distributed homogeneously in both lungs and with thickening of interlobular septa. A 38-year-old man was hospitalised due to chronic lung failure in the course of LCH characterised by small, poorly limited nodular lesions and thin-walled cysts revealed in HRCT scans. For two years of observation, he has suffered five episodes of right pneumothorax. When diagnosing pneumothorax in the middle-age patients, the possible cause of the disease is LAM or LCH. The use of HRCT scanning may enable good determination of the nature and distribution of parenchymal abnormalities found in the diseases.

Recurrence of lymphangioleiomyomatosis after single lung transplantation: new insights into pathogenesis

Lymphangioleiomyomatosis (LAM) is a rare disease found primarily in white women of childbearing age. The present study describes a case of recurrent LAM after single lung transplantation. Double-staining nonisotopic in situ hybridization, immunohistochemistry, and short tandem repeat loci analysis demonstrated that the recurrent LAM lesions originated from the recipient. The data strongly support that metastatic spread of LAM cells or migration of progenitor cells plays an important role in the pathogenesis of LAM.

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.

Metastatic endometrial stromal sarcoma masquerading as pulmonary lymphangioleiomyomatosis

A 39 year old female presented with bilateral pneumothoraces and interstitial shadowing on chest x ray. A diagnosis of lymphangioleiomyomatosis was made following an open lung biopsy. Over the next eight years she developed respiratory failure leading to single lung transplantation but she died in the immediate postoperative period. Necropsy examination and review of the previous open lung biopsy revealed multiple pulmonary metastases from a low grade endometrial stromal sarcoma of the uterus. This case high-lights the importance of an accurate diagnosis before transplantation.

Utility of fine-needle aspiration in the diagnosis of recurrent pulmonary lymphangioleiomyomatosis: a case report

Pulmonary lymphangioleiomyomatosis (PLAM) is a rare disease of undetermined cause that almost exclusively occurs in women of child-bearing age and is characterized by distinct clinical, radiologic, and pathologic findings. PLAM is usually fatal unless treated with hormonal manipulation or lung transplantation. Primary diagnosis usually requires open lung biopsy to demonstrate the characteristic hamartomatous smooth muscle proliferation. To date, cytologic diagnosis of LAM has been limited to an ancillary role. Herein, we report the diagnosis of this neoplasm in a recurrence in an abdominal lymph node using fine-needle aspiration.

[Pulmonary lymphangioleiomyomatosis (LAM). Diagnostic usefulness of immunohistochemical markers]

Lymphangioleiomyomatosis (LAM) is a rare disease of unknown cause affecting the lungs of female patients. Although clinical and radiological findings may suggest LAM, a firm diagnosis is usually made after lung biopsy. Cases of LAM (histochemical diagnosis) or "suggestive of LAM" at the "12 of October" Hospital are reviewed. We applied a battery of immunohistochemical tests not used to date--involving estrogen, progesterone, desmin and HMB45 receptors--that allowed us to classify specimens as having either LAM lesions or lesions with non-LAM muscle proliferation. Smooth muscle proliferation in LAM is a distinct phenotype, such that diagnosis is facilitated by analyzing for immunohistochemical markers such as HMB45. This marker can be detected on formalin-fixed paraffin-embedded sheets in specimens obtained by either open lung or transbronchial biopsy.

Lymphangioleiomyomatosis: recurrence after single lung transplantation

Lymphangioleiomyomatosis (LAM) is a rare disease which afflicts young women of childbearing age. Recently, it has been listed as an indication for lung transplantation. We describe a case of recurrent LAM in a 31-year-old woman occurring in the allograft of a male donor after single lung transplantation. Nonisotopic in situ hybridization shows that the smooth muscle cell proliferation is of donor origin.