Significant improvement of a nevus spilus-type congenital melanocytic nevus with oral selumetinib.

Giant congenital melanocytic nevi (GCMN) can be cosmetically significant and can lead to melanoma. There is no standard pharmacologic treatment for GCMN. We present the case of an 8-year-old female with kaposiform lymphangiomatosis caused by an NRAS mutation whose nevus spilus-type GCMN improved on oral selumetinib.

Kaposiform Lymphangiomatosis as a Cause of Vaginal Bleeding & Discharge: A Case Report.

BACKGROUND: Prepubertal vaginal bleeding is a common presentation for pediatric adolescent gynecologists with a broad differential diagnosis that historically may not have included complex lymphatic anomalies. However, given recent consensus criteria and imaging capabilities, this may be a condition that pediatric adolescent gynecologists see more frequently in the future. CASE: We present a case of a 5-year-old pre-pubertal girl whose only presenting symptoms of a rare complex lymphatic anomaly was copious vaginal bleeding. After three vaginoscopies, two hysteroscopies, two pelvic MRIs, and a percutaneous ultrasound guided core needle biopsy, this patient was eventually diagnosed with Kaposiform lymphangiomatosis at age 9 years-old, and she is now being treated medically with sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, with improvement in her symptoms. SUMMARY AND CONCLUSION: Complex lymphatic anomalies should be considered after initial and secondary workups for pre-pubertal vaginal bleeding or copious vaginal discharge are negative. Furthermore, this case illustrates the value of pelvic MRI in the setting of unknown cause of vaginal bleeding when typical workup is negative.

Generalized lymphatic anomaly: A case report and review of literature.

Generalized lymphatic anomaly (GLA), previously known as lymphangiomatosis, is a rare developmental disease characterized by abnormal proliferation of lymphatic vascular structures that may involve the dermis, soft tissue, bone, and visceral parenchyma. Being an uncommon condition and the lack of specific symptoms often result in a delayed diagnosis or even misdiagnosis, which, in addition to its progressive nature, can lead to dysfunction of vital organs, and ultimately, a poor prognosis. In this report, we present a unique case of GLA in an upper Egyptian female child. Increasing awareness of the possible phenotypic presentations of such anomalies can lead to early diagnosis and possibly more effective management before significant organ damage ensues.

NRASQ61R mutation drives elevated angiopoietin-2 expression in human endothelial cells and a genetic mouse model.

BACKGROUND: Angiopoietin-2 (Ang-2) is increased in the blood of patients with kaposiform lymphangiomatosis (KLA) and kaposiform hemangioendothelioma (KHE). While the genetic causes of KHE are not clear, a somatic activating NRASQ61R mutation has been found in the lesions of KLA patients. PROCEDURE: Our study tested the hypothesis that the NRASQ61R mutation drives elevated Ang-2 expression in endothelial cells. Ang-2 was measured in human endothelial progenitor cells (EPC) expressing NRASQ61R and a genetic mouse model with endothelial targeted NRASQ61R. To determine the signaling pathways driving Ang-2, NRASQ61R EPC were treated with signaling pathway inhibitors. RESULTS: Ang-2 levels were increased in EPC expressing NRASQ61R compared to NRASWT by Western blot analysis of cell lysates and ELISA of the cell culture media. Ang-2 levels were elevated in the blood of NRASQ61R mutant mice. NRASQ61R mutant mice also had reduced platelet counts and splenomegaly with hypervascular lesions, like some KLA patients. mTOR inhibitor rapamycin attenuated Ang-2 expression by NRASQ61R EPC. However, MEK1/2 inhibitor trametinib was more effective blocking increases in Ang-2. CONCLUSIONS: Our studies show that the NRASQ61R mutation in endothelial cells induces Ang-2 expression in vitro and in vivo. In cultured human endothelial cells, NRASQ61R drives elevated Ang-2 through MAP kinase and mTOR-dependent signaling pathways.

Bilateral Renal Lymphangiomatosis: A Case Report and Literature Review.

Renal lymphangiomatosis is a rare congenital condition characterized by the abnormal development of lymphatic channels in the kidney, resulting in cystic dilatations. While more commonly observed in children, it can occur in adults but is extremely rare. Clinical manifestations range from asymptomatic cases to symptoms such as abdominal pain, hypertension, and renal dysfunction. In this case report, we present a rare case of bilateral renal lymphangiomatosis in an eight-year-old male with high blood pressure. Renal ultrasound revealed bilateral kidney enlargement and perinephric hypoechoic collections with septations consistent with lymphangiomatosis. The diagnosis was confirmed through CT imaging which shows bilateral non-enhancing perinephric collections. As a part of the patient's management plan, bilateral perinephric cystic lesions were successfully aspirated without complications. In conclusion, accurate diagnosis is crucial for appropriate management decisions, and treatment primarily focuses on conservative measures to manage associated hypertension, reduce lymphatic fluid accumulation, and alleviate pain, reserving invasive interventions for severe cases or complications.

Diffuse abdominal lymphangiomatosis without tumoral masses: a case report.

Diffuse abdominal lymphangiomatosis is a rare and complex disease. It typically presents with non-specific gastrointestinal symptoms and characteristic cystic lesions or tumoral masses on imaging based on the literature to date. This report presents the rare case of a young man with an atypical form of diffuse abdominal lymphangiomatosis in the complete absence of cystic lesions or lymphangioma tumoral masses, thus presenting a unique diagnostic challenge. It was successively treated by surgery, gastric electrical stimulator, sirolimus, and imatinib.

How we use angiopoietin-2 in the diagnosis and management of vascular anomalies.

The diagnosis of vascular anomalies remains challenging due to significant clinical heterogeneity and uncertain etiology. Evaluation using biopsy and/or genetic testing for somatic variants is invasive, expensive, and prone to sampling error. There is great need for noninvasive and easily measured blood laboratory biomarkers that can aid not only in diagnosis, but also management of treatments for vascular anomalies. Angiopoietin-2, a circulating blood angiogenic factor, is highly elevated in patients with kaposiform hemangioendothelioma with Kasabach-Merritt phenomenon and kaposiform lymphangiomatosis. Here, we describe our clinical experience using serum angiopoietin-2 as a biomarker for diagnosis and monitoring response to treatment.

Differential Diagnosis of Generalized Cystic Lymphangiomatosis: A Literature Review.

BACKGROUND: Generalized cystic lymphangiomatosis (GCL) is a rare disease characterized by the widespread proliferation of lymphatic vessels, often seen in the pediatric patient group. Imaging techniques are instrumental in revealing the extent and morphological features of the disease. OBJECTIVE: The objective of this study is to interpret the radiological findings of GCL and address the differential diagnosis between GCL and other lymphatic malformations in light of the relevant literature data. METHODS: The sample of this retrospective study consisted of six pediatric patients, four males and two females, diagnosed with GCL based on clinical, radiological, and histopathological findings between 2015 and 2022. The age of the patients at the time of diagnosis and their symptoms at admission were obtained from the hospital database. Radiological imaging findings were evaluated in detail based on the involved systems (thorax, abdomen, and musculoskeletal). RESULTS: The median age of the sample, 4/6 were male, was 9 years at admission (min. 3, max. 12). The most common symptom at admission was dyspnea, often accompanied by pleural effusion. Bone involvement was the most common extrathoracic finding. Abdominal involvement was primarily asymptomatic, and the spleen was the most frequently involved organ in the abdomen. CONCLUSION: The diagnosis of GCL is challenging because of its rarity and overlapping diseases. Whole-body magnetic resonance imaging is a valuable tool as it reveals the typical radiological features of GCL and how far it has spread throughout the body.

Abnormalities in C-type lectin-like receptor 2 in a patient with Gorham-Stout disease: the first case report.

Background: Gorham-Stout disease (GSD) is a form of lymphangiomatosis of unknown etiology, characterized by abnormal distribution of lymphatic vessels. Platelets and lymphangiogenesis are closely related via C-type lectin-like receptor 2 (CLEC-2)/podoplanin. Key Clinical Question: Despite similarities between abnormal lymphatic vessels in CLEC-2-deficient mice and patients with GSD, whether CLEC-2 on platelets is involved in GSD pathogenesis is unknown. Clinical Approach: We examined CLEC-2 expression in platelets of a patient with lethal GSD. Most of the patient's platelets expressed aberrant CLEC-2 that was not detectable by certain monoclonal antibodies for human CLEC-2. Further, this population was not activated by a CLEC-2-activating snake venom, rhodocytin. Possible causes of abnormal CLEC-2 including anti-CLEC-2 autoantibodies, podoplanin binding to CLEC-2, and pathogenic CLEC1B gene alteration were excluded. Conclusions: We believe that this is the first report of a patient with structurally and functionally abnormal CLEC-2. CLEC-2 abnormality may be associated with dysregulated lymphangiogenesis in GSD.

Challenging diagnosis of Kaposiform lymphangiomatosis: Unveiling a rare primary lymphatic disorder.

Kaposiform lymphangiomatosis (KLA) is a rare and complex lymphatic anomaly associated with substantial morbidity and mortality. It features diffuse and multifocal malformed lymphatic channels, often leading to diagnostic difficulties due to its uncommon occurrence and non-specific clinical presentation. This case report emphasizes the crucial role of expert radiologists in accurately diagnosing a challenging KLA case initially mistaken for a neoplasm.

Pleural effusion due to lymphangiomatosis and the role of sirolimus: A case report.

Introduction: Lymphangiomatosis is a rare abnormal proliferation of lymphatic vessels involving multiple organs like the brain, lung, heart, spleen, liver, and bones. Lymphangiomas constitute 5.6% of all benign tumors in infancy and adulthood. Case presentation: We report a case of a young lady who presented with constitutional symptoms and progressive dyspnea. Her medical history is significant for muco-cutaneous albinism, diffuse hemangiomas of the bone and viscera, and consumptive coagulopathy status post-splenectomy. After initial investigations, she was found to have right-sided pleural effusion. Pleural fluid analysis indicated chylothorax. She had multiple drainages of the pleural fluid done, and afterward, ligation of the right thoracic duct was performed with a trial of sirolimus, which improved her chylothorax. Clinical discussion: Several case reports have reported positive outcomes with sirolimus in the treatment of lymphangiomatosis. However, larger controlled studies are needed to confirm these findings. Conclusion: Sirolimus is promising as a medical treatment for diffuse pulmonary lymphangiomatosis.

Surgical Treatment for Benign Lymphangioendothelioma After Two Incomplete Excisions: A Case Report and Literature Review.

Benign lymphangioendothelioma (BL) is a rare, poorly identified, slow-growing benign vascular lesion characterized by asymptomatic, solitary, well-demarcated macules, or by mildly infiltrated plaque. We report a case of an atypical BL that arose as a tender, protuberant, flesh-colored mass with cyanotic vesicles, and then progressed to a persistent exudative wound after two incomplete excisions. The patient was also diagnosed with thoracic duct narrowing. Although the stenosis was removed by surgery, the right lower extremity ulceration and exudation did not improve. Thus, we performed a thorough excision and split-thickness skin graft transplant following vacuum sealing drainage, and eventually the patient had a favorable functional and cosmetic outcome. A biopsy revealed irregular, dilated vascular spaces lined with a single layer of flat endothelial cells extending from the superficial dermis to the subcutis that did not reach the striated muscles. Additionally, by reviewing the literature on BL, in this paper we summarize the diverse pathogenic, morphological, and immunohistochemical presentations for this rare disease, as well as the histopathological differential diagnosis of lymphangiomatosis, Kaposi's sarcoma, and angiosarcoma.

Recurrent laryngeal lymphangiomatosis in a patient with Proteus syndrome: A case report.

Proteus syndrome is a rare genetic disease characterized by an asymmetrical growth of individual parts of the body and has only been described in single cases. This patient presented with recurrent manifestations of a laryngeal and hypopharyngeal lymphangioma, which were treated with laser surgery, systemic therapy, and sclerotherapy. The reported data depict the diagnosis and treatment in the department of otorhinolaryngology, head and neck surgery of the university hospital Heidelberg from 2019 until May 2023. The recurrent endoscopy of the upper airway was performed using a flexible HD-endoscope and the Visera Elite video tower from Olympus, Hamburg. The 29-year old female patient initially presented in February 2019 with stridor and exertional dyspnea due to a lymphatic malformation of the left larynx and hypopharynx. In April 2019 there was no improvement by sclerotherapy with Picibanil, so that systemic therapy with the PIK3CA inhibitor alpelisib was initiated (03-07/2020) and discontinued due to a high side effect profile. In the course of 2021-2023, three microlaryngoscopies with laser surgical resection and renewed sclerotherapy of the lymphangioma with Picibanil were carried out due to fluctuating findings. After these interventions a stable disease could be established until May 2023. Laser surgical therapy is currently described as the therapy of choice in lymphangiomas in the head and neck region and also showed the highest effectiveness in our patient. In case of airway obstruction in particular, it can bring rapid symptom relief. Alternatively, and with a lower surgical risk, local improvements have been reported by sclerotherapy, which was less effective in the presented case. Rare syndromic diseases require multidisciplinary collaboration. In the case of laryngeal lymphangiomatosis, other treatment options should be considered in addition to surgical excision, especially in the case of recurrence.

Refractory kaposiform lymphangiomatosis relieved by splenectomy.

Introduction: Kaposiform lymphangiomatosis (KLA) is a rare and complex lymphatic anomaly with a poor prognosis. There is no standard treatment, and drug therapies are the most common therapeutic method. However, some patients' symptoms become gradually aggravated despite medical treatment. Splenectomy may be an alternative option when pharmacological therapies are ineffective. Materials and Methods: We reviewed and evaluated the cases of 3 patients with KLA who ultimately underwent splenectomy. Results: The lesions were diffusely distributed and involved the lungs and spleens of the 3 patients. Laboratory examinations revealed that all three patients had thrombocytopenia and reduced fibrinogen levels. All patients underwent symptomatic splenectomy after the medication failed. Surprisingly, their symptoms greatly improved. Histopathological investigation of the splenic lesions of the three patients confirmed the diagnosis of KLA. Immunohistochemical staining showed positivity for CD31, CD34, podoplanin, Prox-1 and angiopoietin 2 (Ang-2). Discussion: This study aimed to review the features of KLA patients treated by splenectomy and explore the underlying link between splenectomy and prognosis. The reason for the improvement after splenectomy may be related to increased Ang-2 levels and platelet activation in patients with KLA. Future research should seek to develop more targeted drugs based on molecular findings, which may give new hope for the treatment of KLA.

Peri-Renal Lymphangiomatosis: A Case Report Presenting a Rare Disease at a Rarer Location.

Renal lymphangiomatosis is a rare pathology wherein dilatation of perirenal, parapelvic, and intrarenal lymphatics is observed and can occur in both children and adults. It has no gender predilection and can present in unilateral and bilateral forms. Clinical symptomatology ranges from incidental findings to flank pain, hematuria, and abdominal swelling. Radiological appearances may mimic renal cysts, peripelvic cysts, perinephric abscesses, or collections. This emphasizes the importance of developing familiarity with the imaging characteristics of this rare entity. We present the case of an 11-year-old boy whose chief complaint was abdominal distension and bilateral flank pain. The radiological assessment revealed bilateral perinephric collections, which, along with clinical correlation, led to the diagnosis of bilateral peri-renal lymphangiomatosis.

Pathogenic variants in PIK3CA are associated with clinical phenotypes of kaposiform lymphangiomatosis, generalized lymphatic anomaly, and central conducting lymphatic anomaly.

Complex lymphatic anomalies are debilitating conditions characterized by aberrant development of the lymphatic vasculature (lymphangiogenesis). Diagnosis is typically made by history, examination, radiology, and histologic findings. However, there is significant overlap between conditions, making accurate diagnosis difficult. Recently, genetic analysis has been offered as an additional diagnostic modality. Here, we describe four cases of complex lymphatic anomalies, all with PIK3CA variants but with varying clinical phenotypes. Identification of PIK3CA resulted in transition to a targeted inhibitor, alpelisib. These cases highlight the genetic overlap between phenotypically diverse lymphatic anomalies.

Kaposiform Lymphangiomatosis in a Male Adolescent: A Clinical Challenge and the Role of Genetics.

Kaposiform lymphangiomatosis (KLA) is a rare and aggressive generalized lymphatic anomaly (GLA), with distinctive clinical, radiology, morphologic, and genetic features. It does not have a current standard treatment and presents poor overall prognosis. Somatic mutations in the RAS pathway were reported as the likely driver for the majority of patients. We report a case of a 17-year-old male adolescent who was referred to the emergency department due to a severe anemia. Laboratory workup confirmed the anemia and revealed coagulation factor consumption and fibrinolysis. Chest-abdomen-pelvis computed tomography revealed an extensive cervical, mediastinal, abdominal and retroperitoneal "hematoma." During admission, progressive pancytopenia, and disseminated intravascular coagulation were observed, and the hypothesis of a tumor/neoplastic etiology was considered. A thoracoscopy revealed a moderate hemorrhagic pleural effusion and a mediastinal mass resembling a "hemolymphangiomatosis" malformation, which was biopsied. Histology displayed a lymphatic-venous malformation. The patient was presented at the multidisciplinary Vascular Anomalies Center and, due to the complex vascular anomaly diagnosis, oral sirolimus monotherapy was initiated. Four years later, the patient remains clinically stable, with stability of the lesion's dimensions and characteristics. A p.Q61R variant in the NRAS gene [NM_002524.4: c.182A>G, p.(Gln61Arg)], with 5% allelic fraction and 1993x coverage was detected. In conjunction with clinical and pathological findings, it allowed KLA final diagnosis. This case reinforces the importance of a high index of clinical suspicion and highlights the need of referring these cases to referral to Vascular Anomalies Centers.

Case report: Generalized lymphatic anomaly of multiple abdominal organs in a young dog.

A 9-month-old, female Pomeranian dog presented with vomiting and lethargy. Ultrasonography revealed multilobulated anechoic round shape structures at the ovarian and uterine locations. Through computed tomography scan, an extensive non-contrast multilobulated fluid-filled mass suspected of originating from the walls of the ovary, uterus, urinary bladder and rectum was observed. Ovariohysterectomy and urinary bladder biopsy were performed. Histopathological examination revealed numerous cystic lesions lined by plump cuboidal cells believed to be of epithelial origin. Immunohistochemical staining showed that the cyst-like lesions lining cells were strongly positive for lymphatic vessel endothelial hyaluronan receptor 1. Based on these results, lesions were identified as generalized lymphatic anomaly (GLA), in which lymphangiomas develop in multiple organs. After 6 months follow-up, the size of the cysts remaining in the region of the bladder did not undergo much change. GLA should be included in the differential diagnosis when multiple cystic lesions are interspersed in multiple organs.

Diagnosis and treatment of diffuse pulmonary lymphangioma in children: A case report.

The present study aimed to investigate the clinical characteristics of diffuse pulmonary lymphangioma (DPL) in children to improve the diagnosis and treatment of this disease. A case of pediatric DPL was observed for its clinical symptoms, imaging features, lung biopsy pathological characteristics and immunohistochemical phenotypes, and relevant literature was also reviewed. The main clinical manifestations of this pediatric patient were a cough, shortness of breath, hemoptysis, bloody chylothorax and pericardial effusion. Chest computed tomography showed a grid-like shadow and markedly thickened interlobular septa. Pathological examination revealed lymphatic vessel hyperplasia and expansion. Immunohistochemistry showed positive staining of lymphatic endothelial cells CD31 and D2-40. The patient's condition improved after combined treatment with methylprednisone, propranolol, sirolimus and somatostatin, whose bloody chylothorax also achieved good therapeutic effect after conservative treatment. Overall, the clinical and imaging appearances of DPL are lack of characterization, and its clinical manifestations include cough, shortness of breath and chylothorax. Computed tomography may show mesh-like shadows of both lungs and thickened interlobular septa. The definite diagnosis of DPL depends on biopsy pathology. In addition to this case, B-ultrasound-guided puncture biopsy is effective and safe, and propranolol-sirolimus treatment has a certain effect, but the clinical effect may be different. Conservative treatment of pleural effusion can result in better curative effect.

Sirolimus treatment for paediatric head and neck lymphatic malformations: a systematic review.

PURPOSE: This PRISMA-compliant systematic review aimed to assess risks and benefits of sirolimus treatment for paediatric lymphatic malformations by focusing not only on treatment efficacy but also on possible treatment-related adverse events, and treatment combinations with other techniques. METHODS: Search criteria were applied to MEDLINE, Embase, Web of Science, Scopus, Cochrane Library, and ClinicalTrials.gov databases and included all studies published up to March 2022 reporting paediatric lymphatic malformations treated with sirolimus. We selected all original studies that included treatment outcomes. After the removal of duplicates, selection of abstracts and full-text articles, and quality assessment, we reviewed eligible articles for patient demographics, lymphatic malformation type, size or stage, site, clinical response rates, sirolimus administration route and dose, related adverse events, follow-up time, and concurrent treatments. RESULTS: Among 153 unique citations, 19 studies were considered eligible, with reported treatment data for 97 paediatric patients. Most studies (n = 9) were case reports. Clinical response was described for 89 patients, in whom 94 mild-to-moderate adverse events were reported. The most frequently administered treatment regimen was oral sirolimus 0.8 mg/m2 twice a day, with the aim of achieving a blood concentration of 10-15 ng/mL. CONCLUSION: Despite promising results for sirolimus treatment in lymphatic malformation, the efficacy and safety profile of remains unclear due to the lack of high-quality studies. Systematic reporting of known side effects, especially in younger children, should assist clinicians in minimising treatment-associated risks. At the same time, we advocate for prospective multicentre studies with minimum reporting standards to facilitate improved candidate selection.