Somatic IDH1 variant (p.R132C) in an adult male with Maffucci syndrome

Maffucci Syndrome is a rare, highly variable somatic mosaic condition and well-known cancer related gain-of-function variants in either the IDH1 or IDH2 genes have been found in the affected tissues of most reported patients. Features include benign enchondroma and spindle cell hemangioma, with a recognized increased risk of various malignancies. Fewer than 200 cases have been reported, therefore accurate estimates of malignancy risk are difficult to quantify and recommended surveillance guidelines are not available. The same gain-of-function IDH1 and IDH2 variants are also implicated in a variety of other benign and malignant tumors. An adult male presented with several soft palpable lesions on the right upper limb. Imaging and histopathology raised the possibility of Maffucci syndrome. DNA was extracted from peripheral blood lymphocytes and tissue surgically resected from a spindle-cell hemangioma. Sanger sequencing and Droplet-digital PCR analysis of the IDH1 gene was performed. We identified a somatic mosaic c.394C>T (p.R132C) variant in exon 5 of IDH1, in DNA derived from hemangioma tissue at ~ 17% mutant allele frequency. This variant was absent in DNA derived from blood. This variant has been identified in the affected tissue of most reported patients with Maffucci syndrome Although the patient has a potentially targetable variant, and there is a recognized risk of malignant transformation in this condition, a decision was made not to intervene with an IDH1 inhibitor. The reasons and prospects for therapy in this condition are discussed.

Maffucci Syndrome Complicated by Giant Chondrosarcoma in the Left Ankle with an IDH1 R132C Mutation: Case Report

Background: Maffucci syndrome is a rare, nonhereditary congenital mesodermal dysplasia characterized by multiple enchondromas and hemangiomas. It is associated with an increased risk of the development of malignant tumors. We present a case of 45-year-old man with Maffucci syndrome to supplement the clinical manifestations and explore the molecular mechanism of Maffucci syndrome.Results: The patient was underwent amputation surgery to inhibit tumor development and diagnosed as Maffucci syndrome with 1-2 grade giant chondrosarcoma in the left ankle. In addition, the whole exon analysis by Next Generation Sequencing revealed isocitrate dehydrogenase 1 R132C mutation in chondrosarcoma lesions but not in blood DNA. Conclusions: This case report presents the genetic evidence for the inclusion of chondrosarcoma among tumors characterizing Maffucci syndrome. Consequently, it is suggested that patients with Maffucci syndrome should be followed up more actively to exclude neoplasms due to IDH1 R132C somatic mutation.

Maffucci Syndrome with Intrahepatic Cholangiocarcinoma: A Case Report

Maffucci syndrome is characterized by multiple hemangiomas and enchondromas. Somatic mutations in <i>IDH1</i> and <i>IDH2</i> are associated with the development of Maffucci syndrome, and these patients develop various malignant nonskeletal tumors in addition to malignant skeletal tumors. We report a case of Maffucci syndrome with <i>IDH1</i> mutation complicated by intrahepatic cholangiocarcinoma. The patient was a 35-year-old woman who was diagnosed with Maffucci syndrome in childhood. She was referred to our department because of a large hepatic tumor. Serum carcinoembryonic antigen was 27.1 ng/mL upon laboratory examination. CT scanning showed a large low-density tumor (90 × 70 mm) in the right lobe of the liver, and MRI revealed a multilobulated and fibrous tumor, which was observed as high signal intensity on T2- and diffusion-weighted images and low signal intensity on T1-weighted images. Positron emission tomography-CT revealed peritoneal dissemination and cancer spread to the muscles of the back. Finally, she was diagnosed with intrahepatic cholangiocarcinoma with dissemination and metastases. We performed a tumor biopsy to determine a treatment plan for chemotherapy. Sanger sequencing of a tumor biopsy identified a mutation in <i>IDH1</i> at c.394C&#x3e;T (R132C), but the patient died of rapid cancer progression before the chemotherapy could be initiated. Although rare, malignant tumors can develop in patients with Maffucci syndrome; therefore, it is necessary to monitor these tumors through careful and periodic observation.

Maffucci Syndrome, Calcium Homeostasis, and Endocrine Challenges in Management

Maffucci syndrome is a rare disorder characterized by enchondromatosis and hemangiomata. It can occur due to sporadic, de novo, mosaic pathogenic variants in the gene encoding isocitrate dehydrogenase 1 (IDH1) or isocitrate dehydrogenase 2 (IDH2). IDH1 variants are associated with endocrine manifestations, such as pituitary adenomas. However, literature is limited in describing other clinical features and available treatments in severe phenotypes. We report a pediatric patient with uniquely complex and severe Maffucci syndrome. Case: A 5-year-old boy was evaluated by pediatric endocrinology for chronic hypercalcemia as part of a multidisciplinary evaluation of his severe Maffucci syndrome. Past medical history included prematurity, restrictive lung disease, developmental delay, seizures, 2-OH glutaric aciduria, angiomas, and bicytopenia. Physical exam revealed angiomas, scoliosis, and severe bony deformities throughout the entire skeleton. During admission, laboratory assays revealed normal parathyroid hormone, phosphorus, 1,25-OH2D, and C-telopeptide; elevated serum calcium and PTH-related peptide; and low 25-OHD, alkaline phosphatase, and osteocalcin. Low-dose ACTH stimulation test yielded a peak cortisol level of 16.8. A 24-hour urine study confirmed hypercalciuria. Renal ultrasound demonstrated nephrocalcinosis. Skeletal survey revealed diffuse and chondromatous changes of nearly every bone. Whole-exome sequencing detected a presumed, mosaic de novo IDH1 variant. DEXA scan revealed total body BMD z-score of -3.8. Discussion: Hypercalcemia in Maffucci syndrome is a rare phenomenon. The most likely etiology was due to the severe and chronic bony breakdown from the underlying progressive enchondromatosis. Subsequently, the body attempted to adapt to these chronic processes with abnormal mineral homeostasis, as seen in his laboratory assays. Chronic primary hyperparathyroidism was not likely, as his PTH, phosphorus, and 1,25 OH2D levels were not congruent with that diagnosis. Familial hypocalciuric hypercalcemia was not likely, as his urine calcium clearance ratio was &gt;0.01. Finally, his slightly elevated PTHrP level was not due to PTHrP-mediated hypercalcemia of malignancy, as his bone marrow biopsy was negative. The options for short-term hypercalcemia management had their own inherent risks and were not suitable for long-term management. Although there is a lack of pediatric data to guide therapy in Maffucci syndrome, decision was made to proceed with bisphosphonate infusion given the benefits in the setting of his nephrocalcinosis, chronic hypercalcemia, and results of his DEXA scan. Given the rarity of Maffucci syndrome, few characteristics are well-described in the pediatric population. A multidisciplinary approach is necessary to review the severity of the disease and to determine the best treatment approach based on this information.

Monomelic Maffucci syndrome

Maffucci syndrome is a rare congenital, non-hereditary condition characterised by presence of multiple enchondromas and haemangiomas. Enchondromatous lesions affecting epiphysial growth plates can lead to angular deformities and leg-length discrepancy in the lower limb. We describe a 12-year-old girl with monomelic Maffucci syndrome affecting her left lower limb. She presented with progressive genu valgus deformity of her left knee. This caused her to limp during her gait and was a cosmetic dissatisfaction. The deformity affected her quality of life. She underwent a supracondylar distal femoral corrective osteotomy with a successful clinical outcome and restoration of her gait and cosmetic deformity.