scholarly journals RARE-55. CHALLENGES AND SPECIFIC STRATEGIES FOR CONSTITUTIONAL MISMATCH REPAIR DEFICIENCY SYNDROME IN LOW RESOURCE SETTINGS. ON BEHALF OF THE INTERNATIONAL RRD CONSORTIUM IN LOW RESOURCE SETTINGS PANEL

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii454-iii454
Author(s):  
Rejin Kebudi ◽  
Nisreen Amayiri N ◽  
Malak Abedalthagafi ◽  
Asim Noor Rana ◽  
Slman Kirmani ◽  
...  

Abstract Germline biallelic mutations in one of the mismatch repair genes (MSH2/MSH6/MLH1/PMS2 results in constitutional mismatch repair deficiency (CMMRD), a condition associated with multiple tumors arising from multiple organs during childhood, and these individuals rarely reach adulthood. The paucity of information with respect to these conditions leads to mismanagement and may be a factor in the high mortality of patients with CMMRD. Two international consortia, the European CARE4CMMRD, and the international replication repair deficiency (RRD) consortium, are addressing the many challenges associated with this condition. To address specific issues surrounding the management of CMMRD in low and middle income countries (LMIC), a multidisciplinary taskforce of 11 specialists from nine countries was formed. Preliminary conclusions are: 1) Immunohistochemistry for CMMRD should be considered for all patients with suggestive clinical features. In countries where CMMRD is common, malignant gliomas, colon cancers and T cell lymphomas should be stained routinely as the prevalence of CMMRD in these tumors can exceed 40%. 2) Temozolomide should not be used in the management of malignant glioma. By contrast, preclinical studies have suggested increased sensitivity to nitrosoureas. For the management of CMMRD related lymphoma and leukemia, mercaptopurines should not be avoided or discontinued as a part of the standard of care before more data are collected. 3) Management with checkpoint inhibitors should be limited to centers with intensive care units and expertise in complex supportive care to manage side effects of immune therapy. 4) Surveillance protocols have demonstrated long term survival benefits and should be implemented in LMIC.

2021 ◽  
Vol 22 (9) ◽  
pp. 4629
Author(s):  
Cristina Carrato ◽  
Carolina Sanz ◽  
Ana María Muñoz-Mármol ◽  
Ignacio Blanco ◽  
Marta Pineda ◽  
...  

Biallelic germline mismatch repair (MMR) gene (MLH1, MSH2, MSH6, and PMS2) mutations are an extremely rare event that causes constitutional mismatch repair deficiency (CMMRD) syndrome. CMMRD is underdiagnosed and often debuts with pediatric malignant brain tumors. A high degree of clinical awareness of the CMMRD phenotype is needed to identify new cases. Immunohistochemical (IHC) assessment of MMR protein expression and analysis of microsatellite instability (MSI) are the first tools with which to initiate the study of this syndrome in solid malignancies. MMR IHC shows a hallmark pattern with absence of staining in both neoplastic and non-neoplastic cells for the biallelic mutated gene. However, MSI often fails in brain malignancies. The aim of this report is to draw attention to the peculiar IHC profile that characterizes CMMRD syndrome and to review the difficulties in reaching an accurate diagnosis by describing the case of two siblings with biallelic MSH6 germline mutations and brain tumors. Given the difficulties involved in early diagnosis of CMMRD we propose the use of the IHC of MMR proteins in all malignant brain tumors diagnosed in individuals younger than 25 years-old to facilitate the diagnosis of CMMRD and to select those neoplasms that will benefit from immunotherapy treatment.


2018 ◽  
Vol 06 (08) ◽  
pp. E1037-E1043 ◽  
Author(s):  
Y. Shimamura ◽  
C. M. Walsh ◽  
S. Cohen ◽  
M. Aronson ◽  
U. Tabori ◽  
...  

Abstract Background and study aims Constitutional mismatch repair deficiency (CMMRD) syndrome, also known as biallelic mismatch repair deficiency (BMMRD) syndrome is a rare autosomal-recessive genetic disorder that has a high mortality due to malignancy in childhood and early adulthood. The small bowel phenotype in CMMRD is not well described and surveillance protocols for small bowel cancer have not been well established. This study was conducted to evaluate the usefulness and clinical impact of video capsule endoscopy (VCE) for small bowel surveillance. Patients and methods We retrospectively reviewed the prospectively maintained International CMMRD Consortium database. Treating physicians were contacted and VCE report data were extracted using a standardized template. Results Among 58 patients included in the database, 38 VCE reports were collected from 17 patients. Polypoid lesions were first detected on VCE at a median age of 14 years (range: 4 – 17). Of these, 39 % in 7 patients (15/38) showed large polypoid lesions (> 10 mm) or multiple polyps that prompted further investigations. Consequently, three patients were diagnosed with small bowel neoplasia including one patient with adenocarcinoma. Small bowel neoplasia and/or cancer were confirmed histologically in 35 % of the patients (6/17) who had capsule surveillance and the lesions in half of these patients were initially visualized on VCE. Multiple polyps were identified on eight VCEs that were completed on three patients. Ten VCEs (28 %) were incomplete due to slow bowel transit; none required capsule removal. Conclusions Small bowel surveillance in patients with CMMRD should be initiated early in life. VCE has the potential to detect polyps; however, small bowel neoplasias are often proximal and can be missed, emphasizing the importance of concurrent surveillance with other modalities. Meeting presentations Digestive Disease Week 2017 and World Congress of Pediatric Gastroenterology, Hepatology and Nutrition 2016.


Sign in / Sign up

Export Citation Format

Share Document