Multifocal micronodular pneumocyte hyperplasia: computed tomographic appearance and follow-up in tuberous sclerosis complex

A Comparison of Clinical and Radiological Presentations of Sporadic and Tuberous Sclerosis Complex-Associated Lymphangioleiomyomatosis

This research aims to compare and assess the clinical and radiological presentations of tuberous sclerosis complex (TSC)-associated lymphangioleiomyomatosis (LAM) and sporadic LAM. A retrospective medical record review was conducted for 90 patients with confirmed LAM diagnoses. Radiologists who were blinded to the LAM type evaluated CT images of the chest and abdomen for the presence of four CT phenotypes: multiple sclerotic bone lesions (SBLs), multifocal micronodular pneumocyte hyperplasia (MMPH), hepatic fat-containing lesions, and cardiac fat-containing lesions. Statistical analyses were then completed to analyze the differences between TSC-LAM and sporadic LAM. Sporadic LAM patients reported a greater number of clinical symptoms at the time of diagnosis than TSC-LAM patients. All four CT phenotypes were present among the TSC-LAM patient population, whereas hepatic fat containing lesions were the only phenotype present in sporadic LAM patients evaluated in this study. The clinical and radiological presentations of sporadic LAM and TSC-LAM differ significantly, suggesting that the diagnostic criteria for sporadic LAM and/or TSC itself could be adapted accordingly. However, the similarities in the presentation of the LAM types are also important to note as these trends inform theories surrounding the potential underlying pathogenic mechanisms of sporadic LAM.

Lymphangioleiomyomatosis as a potent lung cancer risk factor: Insights from a Japanese large cohort study

BACKGROUND AND OBJECTIVE

Lymphangioleiomyomatosis (LAM) is a rare neoplastic disease associated with the functional tumour suppressor genes TSC1 and TSC2 and causes structural destruction in the lungs, which could potentially increase the risk of lung cancer. However, this relationship remains unclear because of the rarity of the disease.

METHODS

We investigated the relative risk of developing lung cancer among patients diagnosed with LAM between 2001 and 2022 at a single high-volume centre in Japan, using data from the Japanese Cancer Registry as the reference population. Next-generation sequencing (NGS) was performed in cases where tumour samples were available.

RESULTS

Among 642 patients diagnosed with LAM (sporadic LAM, n = 557; tuberous sclerosis complex-LAM, n = 80; unclassified, n = 5), 13 (2.2%) were diagnosed with lung cancer during a median follow-up period of 5.13 years. All patients were female, 61.5% were never smokers, and the median age at lung cancer diagnosis was 53 years. Eight patients developed lung cancer after LAM diagnosis. The estimated incidence of lung cancer was 301.4 cases per 100,000 person-years, and the standardized incidence ratio was 13.6 (95% confidence interval, 6.2-21.0; p = 0.0008). Actionable genetic alterations were identified in 38.5% of the patients (EGFR: 3, ALK: 1 and ERBB2: 1). No findings suggested loss of TSC gene function in the two patients analysed by NGS.

CONCLUSION

Our study revealed that patients diagnosed with LAM had a significantly increased risk of lung cancer. Further research is warranted to clarify the carcinogenesis of lung cancer in patients with LAM.

[Genetic diffuse cystic lung disease in adults]

Multiple cystic lung diseases comprise a wide range of various diseases, some of them of genetic origin. Lymphangioleiomyomatosis (LAM) is a disease occurring almost exclusively in women, sporadically or in association with tuberous sclerosis complex (TSC). Patients with LAM present with lymphatic complications, renal angiomyolipomas and cystic lung disease responsible for spontaneous pneumothoraces and progressive respiratory insufficiency. TSC and LAM have been ascribed to mutations in TSC1 or TSC2 genes. Patients with TSC are variably affected by cutaneous, cognitive and neuropsychiatric manifestations, epilepsy, cerebral and renal tumors, usually of benign nature. Birt-Hogg-Dubé syndrome is caused by mutations in FLCN encoding folliculin. This syndrome includes lung cysts of basal predominance, cutaneous fibrofolliculomas and various renal tumors. The main complications are spontaneous pneumothoraces and renal tumors requiring systematic screening. The mammalian target of rapamycin (mTOR) pathway is involved in the pathophysiology of TSC, sporadic LAM and Birt-Hogg-Dubé syndrome. MTOR inhibitors are used in LAM and in TSC while Birt-Hogg-Dubé syndrome does not progress towards chronic respiratory failure. Future challenges in these often under-recognized diseases include the need to reduce the delay to diagnosis, and to develop potentially curative treatments. In France, physicians can seek help from the network of reference centers for the diagnosis and management of rare pulmonary diseases.

Recurrent pneumothoraces with diffuse small ground-glass and solid nodules

Multifocal micronodular pneumocyte hyperplasia (MMPH) is the lesser known pulmonary manifestation of tuberous sclerosis. It manifests radiologically as diffuse small ground-glass and solid nodules. Accurate diagnosis is essential as it can be mistaken for miliary tuberculosis or malignant lesions which necessitates specific treatment. Constellation of radiological features such as multicentric disease at onset and stability over time can help to distinguish MMPH from its differentials. Histologically, MMPH is characterized by hamartomatous proliferation of type II pneumocytes with a lack of high nuclear to cytoplasmic ratio. MMPH confers a benign prognosis unlike its differentials. Therefore, accurate diagnosis is paramount in ensuring appropriate care is delivered. Here, we describe the radiological and histological features of MMPH in a patient with genetically proven tuberous sclerosis complex and co-existing lymphangioleiomyomatosis.

Updated International Tuberous Sclerosis Complex Diagnostic Criteria and Surveillance and Management Recommendations

BACKGROUND

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disease affecting multiple body systems with wide variability in presentation. In 2013, Pediatric Neurology published articles outlining updated diagnostic criteria and recommendations for surveillance and management of disease manifestations. Advances in knowledge and approvals of new therapies necessitated a revision of those criteria and recommendations.

METHODS

Chairs and working group cochairs from the 2012 International TSC Consensus Group were invited to meet face-to-face over two days at the 2018 World TSC Conference on July 25 and 26 in Dallas, TX, USA. Before the meeting, working group cochairs worked with group members via e-mail and telephone to (1) review TSC literature since the 2013 publication, (2) confirm or amend prior recommendations, and (3) provide new recommendations as required.

RESULTS

Only two changes were made to clinical diagnostic criteria reported in 2013: "multiple cortical tubers and/or radial migration lines" replaced the more general term "cortical dysplasias," and sclerotic bone lesions were reinstated as a minor criterion. Genetic diagnostic criteria were reaffirmed, including highlighting recent findings that some individuals with TSC are genetically mosaic for variants in TSC1 or TSC2. Changes to surveillance and management criteria largely reflected increased emphasis on early screening for electroencephalographic abnormalities, enhanced surveillance and management of TSC-associated neuropsychiatric disorders, and new medication approvals.

CONCLUSIONS

Updated TSC diagnostic criteria and surveillance and management recommendations presented here should provide an improved framework for optimal care of those living with TSC and their families.

Lymphangioleiomyomatosis Association with Underlying Genotype in Patients with Tuberous Sclerosis Complex

Rationale: Lymphangioleiomyomatosis (LAM) is a female-predominant lung disease caused by mutations in the tuberous sclerosis complex (TSC) genes TSC1 and TSC2.Objectives: To examine the association between TSC mutation subtypes and the prevalence of LAM in women with TSC.Methods: Adult women seen at the Cincinnati Children's Hospital Medical Center's TSC clinic were stratified into the following three groups: those with TSC1 mutation, those with TSC2 mutation, and those with no mutation identified (NMI). Individual TSC manifestations were ascertained by blinded review of chest computed tomographic scans (LAM, multifocal micronodular pneumocyte hyperplasia, and sclerotic bone lesions) and chart review (all other manifestations). The association between mutation status and TSC manifestations was assessed by the Wilcoxon rank-sum test.Results: Our cohort consisted of 55 TSC women, including 30/55 (55%) with TSC2, 12/55 (22%) with TSC1, and 13/55 (23%) with NMI. Twenty-three women (42%) had characteristic cysts consistent with LAM, of whom 16 had TSC2 mutations and seven had NMI. The prevalence of LAM was higher in women with TSC2 mutations compared with women with TSC1 mutations (16/29 [55%] vs. 0/12; P = 0.003). Similarly, renal angiomyolipomas were more common in women with TSC2 mutations compared with women with TSC1 mutations (29/30 [97%] vs. 6/12 [50%]; P = 0.01). There was no association between TSC mutation subtype and the presence of multifocal micronodular pneumocyte hyperplasia, sclerotic bone lesions, and skin or brain involvement. Serum VEGF-D (vascular endothelial growth factor-D) concentrations (median [95% confidence interval]) tended to be higher in patients harboring TSC2 mutations compared with patients with TSC1 mutations (725 pg/ml [612-1,317] vs. 331 pg/ml [284-406]; P = 0.03) and in patients with LAM compared with patients without LAM (725 pg/ml [563-1,609] vs. 429 pg/ml [357-773]; P = 0.02).Conclusions: LAM and angiomyolipomas are more common in women with TSC harboring TSC2 mutations compared with women with TSC1 mutations. Serum VEGF-D is a useful biomarker to suggest the presence of LAM in women with TSC.

Tuberous sclerosis complex for the pulmonologist

Tuberous sclerosis complex (TSC) is a rare multisystem genetic disorder affecting almost all organs with no sex predominance. TSC has an autosomal-dominant inheritance and is caused by a heterozygous mutation in either the TSC1 or TSC2 gene leading to hyperactivation of the mammalian target of rapamycin (mTOR). TSC is associated with several pulmonary manifestations including lymphangioleiomyomatosis (LAM), multifocal micronodular pneumocyte hyperplasia (MMPH) and chylous effusions. LAM is a multisystem disorder characterised by cystic destruction of lung parenchyma, and may occur in either the setting of TSC (TSC-LAM) or sporadically (S-LAM). LAM occurs in 30–40% of adult females with TSC at childbearing age and is considered a nonmalignant metastatic neoplasm of unknown origin. TSC-LAM is generally milder and, unlike S-LAM, may occur in males. It manifests as multiple, bilateral, diffuse and thin-walled cysts with normal intervening lung parenchyma on chest computed tomography. LAM is complicated by spontaneous pneumothoraces in up to 70% of patients, with a high recurrence rate. mTOR inhibitors are the treatment of choice for LAM with moderately impaired lung function or chylous effusion. MMPH, manifesting as multiple solid and ground-glass nodules on high-resolution computed tomography, is usually harmless with no need for treatment.

Tuberous sclerosis complex is associated with diverse pulmonary manifestations including LAM, multiple micronodular pneumocyte hyperplasia and chylous effusions. LAM occurs in 30–40% of adult females with tuberous sclerosis complex.https://bit.ly/3iLqZ08

Uncommon radiologic computed tomography appearances of the chest in patients with lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare destructive lung disease characterized by multiple thin-walled pulmonary cysts. The currently proposed diagnostic algorithm emphasizes the characteristic cystic appearance on high-resolution computed tomography (HRCT) so uncommon HRCT appearances present challenges to establishing the proper LAM diagnosis. The objective of this study is to accrue uncommon chest HRCT appearances, determine frequencies in both tuberous sclerosis complex (TSC)-associated LAM (TSC-LAM) and sporadic LAM (S-LAM) patients. 311 females referred to our hospital, including 272 S-LAM patients (mean age 39.2 years) and 39 TSC-LAM patients (mean age 38.3 years), were retrospectively evaluated. We found 2 types of radiologic findings likely to make HRCT cyst appearance atypical: characteristics of the cyst itself and uncommon findings in addition to cysts. We found that approximately 80% of LAM patients, whether TSC-associated or sporadic, showed typical HRCT appearance with mild to severe cystic destruction. The remaining 20% displayed unusual profiles in cyst appearance as well as additional findings aside from cyst: the former includes large cyst, thickened walls, and irregularly shaped whereas the latter includes ground glass attenuation and diffuse noncalcified nodules. It is important to be aware of various radiologic findings that make HRCT cystic appearance atypical of LAM.

Effect of everolimus on multifocal micronodular pneumocyte hyperplasia in tuberous sclerosis complex

Multifocal micronodular pneumocyte hyperplasia (MMPH) is a benign proliferation of alveolar type II cells presenting as multiple pulmonary nodules at chest imaging, which is frequently seen in patients with tuberous sclerosis complex (TSC). We report a case of a woman with TSC and MMPH who received everolimus, a mechanistic target of rapamycin (mTOR) inhibitor, for the treatment of a subependymal giant cell astrocytoma (SEGA). After 3 months of therapy, a remarkable decrease in density of all pulmonary MMPH lesions was observed, without any change in size. This shows that everolimus is active on MMPH similarly to its effects on SEGA, renal angiomyolipomas, and pulmonary lymphangioleiomyomatosis in TSC, and suggests that the dysregulated activation of mTOR which characterizes TSC also plays a role in the pathogenesis of MMPH.

Phakomatoses

Phakomatoses present with characteristic findings on the skin, central or peripheral nervous system, and tumors. Neurofibromatosis type 1 is the most common syndrome and is characterized by Café-au-lait macules, intertriginous freckling, Lisch nodules, and tumors including neurofibromas, malignant peripheral nerve sheath tumors, and gliomas. Tuberous Sclerosis Complex is characterized by benign hamartomas presenting with hypomelanotic macules, shagreen patches, angiofibromas, confetti lesions and tumors including cortical tubers, subependymal nodules, subependymal giant cell astrocytomas and tumors of the kidney, lung, and heart. Managing these disorders requires disease specific supportive care, tumor monitoring, surveillance for selected cancers, and treatment of comorbid conditions.

Pulmonary manifestations in tuberous sclerosis complex

Tuberous sclerosis complex has manifestations in many organ systems, including brain, heart, kidney, skin, and lung. The primary manifestations in the lung are lymphangioleiomyomatosis (LAM) and multifocal micronodular pneumocyte hyperplasia (MMPH). LAM affects almost exclusively women, and causes cystic lung destruction, pneumothorax, and chylous pleural effusions. LAM can lead to dyspnea, oxygen dependence, and respiratory failure, with more rapid disease progression during the premenopausal years. In contrast, MMPH affects men and women equally, causing small nodular pulmonary deposits of type II pneumocytes that rarely progress to symptomatic disease. Here, we review the clinical features and pathogenesis of LAM and MMPH.

Hereditary Renal Cystic Disorders: Imaging of the Kidneys and Beyond

The purpose of this article is to review the hereditary renal cystic diseases that can manifest in children and adults, with specific attention to pathogenesis and imaging features. Various common and uncommon hereditary renal cystic diseases are reviewed in terms of their underlying etiology, including the involved genetic mutations and the affected proteins and cellular structures. Focus is placed on the morphologic findings in each condition and the features that distinguish one disorder from another. The two most common categories of hereditary renal cystic disease are (a) the ciliopathic disorders, which are related to mutations affecting the primary cilia (called "ciliopathies"), and (b) the phakomatoses. Autosomal dominant polycystic kidney disease, autosomal recessive polycystic kidney disease, and the "medullary cystic disease complex" are all ciliopathies but have different phenotypes. Tuberous sclerosis complex and the associated "contiguous gene syndrome," as well as von Hippel-Lindau syndrome, are phakomatoses that can manifest with cystic renal lesions but have uniquely different extrarenal manifestations. Finally, DICER1 mutations can manifest with renal cystic lesions (typically, cystic nephromas) in patients predisposed to other malignancies in the chest, ovaries, and thyroid. Although some overlap exists in the appearance of the renal cysts associated with each of these diseases, there are clear morphologic differences (eg, cyst size, location, and complexity) that are emphasized in this review. To improve patient outcomes, it is important for the radiologist to recognize the various hereditary renal cystic diseases so that a correct diagnosis is assigned and so that the patient is adequately evaluated and followed up. ^©RSNA, 2017.

Hamartomas from head to toe: an imaging overview

Hamartomas are tumours composed of mesenchymal tissues such as cartilage, fat, connective tissue and smooth muscle and can be found in virtually any organ system. These masses commonly develop sporadically, but are also seen in certain syndromes such as tuberous sclerosis or Carney triad. While their imaging appearance varies depending on the organ they arise from, findings are usually unique and a diagnosis can be confidently made. Radiologists must be aware of the clinical and imaging presentations of these lesions with the particular goal of avoiding unnecessary studies or invasive procedures. Furthermore, knowledge of common syndromic entities is crucial, as the radiologist may be the first to suggest the diagnosis.

Rapamycin and rapalogs for tuberous sclerosis complex

BACKGROUND

Previous studies have shown potential benefits of rapamycin or rapalogs for treating people with tuberous sclerosis complex. Although everolimus (a rapalog) is currently approved by the FDA (U.S. Food and Drug Administration) and the EMA (European Medicines Agency) for tuberous sclerosis complex-associated renal angiomyolipoma and subependymal giant cell astrocytoma, applications for other manifestations of tuberous sclerosis complex have not yet been established. A systematic review is necessary to establish the clinical value of rapamycin or rapalogs for various manifestations in tuberous sclerosis complex.

OBJECTIVES

To determine the effectiveness of rapamycin or rapalogs in people with tuberous sclerosis complex for decreasing tumour size and other manifestations and to assess the safety of rapamycin or rapalogs in relation to their adverse effects.

SEARCH METHODS

Relevant studies were identified by authors from the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, and clinicaltrials.gov. Relevant resources were also searched by the authors, such as conference proceedings and abstract books of conferences, from e.g. the Tuberous Sclerosis Complex International Research Conferences, other tuberous sclerosis complex-related conferences and the Human Genome Meeting. We did not restrict the searches by language as long as English translations were available for non-English reports.Date of the last searches: 14 March 2016.

SELECTION CRITERIA

Randomized or quasi-randomized studies of rapamycin or rapalogs in people with tuberous sclerosis complex.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by two authors using standard acquisition forms. The data collection was verified by one author. The risk of bias of each study was independently assessed by two authors and verified by one author.

MAIN RESULTS

Three placebo-controlled studies with a total of 263 participants (age range 0.8 to 61 years old, 122 males and 141 females, with variable lengths of study duration) were included in the review. We found high-quality evidence except for response to skin lesions which was judged to be low quality due to the risk of attrition bias. Overall, there are 175 participants in the treatment arm (rapamycin or everolimus) and 88 in the placebo arm. Participants all had tuberous sclerosis complex as proven by consensus diagnostic criteria as a minimum. The quality in the description of the study methods was mixed, although we assessed most domains as having a low risk of bias. Blinding of treatment arms was successfully carried out in all of the studies. However, two studies did not report allocation concealment. Two of the included studies were funded by Novartis Pharmaceuticals.Two studies (235 participants) used oral (systemic) administration of everolimus (rapalog). These studies reported response to tumour size in terms of the number of individuals with a reduction in the total volume of tumours to 50% or more relative to baseline. Significantly more participants in the treatment arm (two studies, 162 participants, high quality evidence) achieved a 50% reduction in renal angiomyolipoma size, risk ratio 24.69 (95% confidence interval 3.51 to 173.41) (P = 0.001). For the sub-ependymal giant cell astrocytoma, our analysis of one study (117 participants, high quality evidence) showed significantly more participants in the treatment arm achieved a 50% reduction in tumour size, risk ratio 27.85 (95% confidence interval 1.74 to 444.82) (P = 0.02). The proportion of participants who showed a skin response from the two included studies analysed was significantly increased in the treatment arms, risk ratio 5.78 (95% confidence interval 2.30 to 14.52) (P = 0.0002) (two studies, 224 participants, high quality evidence). In one study (117 participants), the median change of seizure frequency was -2.9 in 24 hours (95% confidence interval -4.0 to -1.0) in the treatment group versus -4.1 in 24 hour (95% confidence interval -10.9 to 5.8) in the placebo group. In one study, one out of 79 participants in the treatment group versus three of 39 in placebo group had increased blood creatinine levels, while the median percentage change of forced expiratory volume at one second in the treatment arm was -1% compared to -4% in the placebo arm. In one study (117 participants, high quality evidence), we found that those participants who received treatment had a similar risk of experiencing adverse events compared to those who did not, risk ratio 1.07 (95% confidence interval 0.96 - 1.20) (P = 0.24). However, as seen from two studies (235 participants, high quality evidence), the treatment itself led to significantly more adverse events resulting in withdrawal, interruption of treatment, or reduction in dose level, risk ratio 3.14 (95% confidence interval 1.82 to 5.42) (P < 0.0001).One study (28 participants) used topical (skin) administration of rapamycin. This study reported response to skin lesions in terms of participants' perception towards their skin appearance following the treatment. There was a tendency of an improvement in the participants' perception of their skin appearance, although not significant, risk ratio 1.81 (95% confidence interval 0.80 to 4.06, low quality evidence) (P = 0.15). This study reported that there were no serious adverse events related to the study product and there was no detectable systemic absorption of the rapamycin during the study period.

AUTHORS' CONCLUSIONS

We found evidence that oral everolimus significantly increased the proportion of people who achieved a 50% reduction in the size of sub-ependymal giant cell astrocytoma and renal angiomyolipoma. Although we were unable to ascertain the relationship between the reported adverse events and the treatment, participants who received treatment had a similar risk of experiencing adverse events as compared to those who did not receive treatment. Nevertheless, the treatment itself significantly increased the risk of having dose reduction, interruption or withdrawal. This supports ongoing clinical applications of oral everolimus for renal angiomyolipoma and subependymal giant cell astrocytoma. Although oral everolimus showed beneficial effect on skin lesions, topical rapamycin only showed a non-significant tendency of improvement. Efficacy on skin lesions should be further established in future research. The beneficial effects of rapamycin or rapalogs on tuberous sclerosis complex should be further studied on other manifestations of the condition.

Women with TSC: Relationship between Clinical, Lung Function and Radiological Features in a Genotyped Population Investigated for Lymphangioleiomyomatosis

The advent of pharmacological therapies for lymphangioleiomyomatosis (LAM) has made early diagnosis important in women with tuberous sclerosis complex (TSC), although the lifelong cumulative radiation exposure caused by chest computer tomography (CT) should not be underestimated. We retrospectively investigated, in a cohort of TSC outpatients of San Paolo Hospital (Milan, Italy) 1) the role of pulmonary function tests (PFTs) for LAM diagnosis, 2) the association between LAM and other features of TSC (e.g. demography, extrapulmonary manifestations, genetic mutations, etc.), and 3) the characteristics of patients with multifocal micronodular pneumocyte hyperplasia (MMPH). Eighty-six women underwent chest CT scan; pulmonary involvement was found in 66 patients (77%; 49% LAM with or without MMPH, and 28% MMPH alone). LAM patients were older, with a higher rate of pneumothorax, presented more frequently with renal and hepatic angiomyolipomas, and tended to have a TSC2 mutation profile. PFTs, assessed in 64% of women unaffected by cognitive impairments, revealed a lower lung diffusion capacity in LAM patients. In multivariate analysis, age, but not PFTs, resulted independently associated with LAM diagnosis. Patients with MMPH alone did not show specific clinical, functional or genetic features. A mild respiratory impairment was most common in LAM-TSC patients: In conclusions, PFTs, even if indicated to assess impairment in lung function, are feasible in a limited number of patients, and are not significantly useful for LAM diagnosis in women with TSC.

Tuberous sclerosis complex diagnostic criteria update: recommendations of the 2012 Iinternational Tuberous Sclerosis Complex Consensus Conference

BACKGROUND

Tuberous sclerosis complex is highly variable in clinical presentation and findings. Disease manifestations continue to develop over the lifetime of an affected individual. Accurate diagnosis is fundamental to implementation of appropriate medical surveillance and treatment. Although significant advances have been made in the past 15 years in the understanding and treatment of tuberous sclerosis complex, current clinical diagnostic criteria have not been critically evaluated or updated since the last clinical consensus conference in 1998.

METHODS

The 2012 International Tuberous Sclerosis Complex Consensus Group, comprising 79 specialists from 14 countries, was organized into 12 subcommittees, each led by a clinician with advanced expertise in tuberous sclerosis complex and the relevant medical subspecialty. Each subcommittee focused on a specific disease area with important diagnostic implications and was charged with reviewing prevalence and specificity of disease-associated clinical findings and their impact on suspecting and confirming the diagnosis of tuberous sclerosis complex.

RESULTS

Clinical features of tuberous sclerosis complex continue to be a principal means of diagnosis. Key changes compared with 1998 criteria are the new inclusion of genetic testing results and reducing diagnostic classes from three (possible, probable, and definite) to two (possible, definite). Additional minor changes to specific criterion were made for additional clarification and simplification.

CONCLUSIONS

The 2012 International Tuberous Sclerosis Complex Diagnostic Criteria provide current, updated means using best available evidence to establish diagnosis of tuberous sclerosis complex in affected individuals.

Reversed Halo Sign in Tuberous Sclerosis Complex

We describe a reversed halo sign in a teenage girl with tuberous sclerosis complex (TSC). Lung manifestations of TSC include lung cysts corresponding to lymphangioleiomyomatosis and small nodules indicating multifocal micronodular pneumocyte hyperplasia (MMPH). However, a reversed halo sign in TSC has never been reported. The lesion was microscopically consistent with MMPH. Immunohistological findings also supported the notion that the lesion is associated with TSC.