Pulmonary toxicity is a rare complication of Rituximab therapy. Although Rituximab is relatively safe and can be administered in an outpatient setting, Rituximab-associated lung disease has been reported and may cause mortality despite early detection. Typically the pulmonary toxicity occurs at around the fourth cycle of Rituximab. High index of suspicion is crucial and other concurrent pathology such as infective causes should be excluded. Radiological imaging and histological confirmation should be obtained and early treatment with corticosteroid should be initiated. Patients should receive counselling regarding respiratory symptoms and possible pulmonary toxicity.
Rituximab ; Lung Diseases

Introduction: Calreticulin (CALR) mutations are one of the molecular markers that has been incorporated for the diagnosis of myeloproliferative neoplasms (MPN) in the revised 2017 WHO Classification of Haematopoietic and Lymphoid Tumors. This study was performed to determine the prevalence of CALR mutations in patients with MPN diagnosed in UKMMC and to compare their demographics plus laboratory features with other MPN patients. Methods: A total of 59 MPN patients who tested negative for JAK2V617Fmutation were selected and 21 MPN patients positive for JAK2V617F were included as controls. Screening for CALR exon 9 was done by multiplex polymerase chain reaction (PCR) followed by Sanger sequencing. Results: A total of six JAK2 V617F negative MPN samples were found to be positive for CALR mutations. Out of these six, three patients with CALR mutations were of type I mutation, two were type II while one was a mutation in the stretch III region. None of the twenty one JAK2 V617F positive MPN samples were positive for CALR mutation. Clinical phenotypes for those positive for CALR were restricted to Essential Thrombocythemia (ET), Primary Myelofibrosis (PMF) and one case of atypical Chronic Myeloid Leukaemia (CML). Conclusion: CALR mutations constituted 10.16% from the MPN patients who were negative for JAK2V617F mutation with no significant differences in platelet counts, hemoglobin (Hb), hematocrit and white cell counts as compared to MPN patients with JAK2 V617F mutations. Testing for CALR mutations among those who are negative for JAK2V617F within Malaysian population maybe worthwhile and require larger scale studies.

Introduction: Differences in baseline characteristics and response to treatment in different age groups of patients with chronic myeloid leukaemia (CML) in resource-limited countries have not been extensively studied. We aimed to determine the differences in clinicopathological parameters at diagnosis and response to imatinib in adult CML patients with younger (under 60 years; YCML) and older (60 years and older; OCML) age treated at our institution from March 2001 to March 2021. Methods: A retrospective analysis of consecutive adult CML patients receiving imatinib was performed. Clinicopathological parameters and treatment response were reviewed and analysed using hospital medical records and electronic data reports. Results: The median age at diagnosis was 50 years. OCML patients (n=17) had significantly more comorbidities. The YCML group (n=50) generally had a palpable spleen >5cm from the costal margin, mild anaemia, hyperleukocytosis and thrombocytosis. A starting dose of 400 mg/day was observed in 84% of YCML and in 65% of OCML. Cumulative complete cytogenetic response was 50% in YCML versus 70.6% in OCML, p=0.158. OCML tended to have a higher percentage of major molecular response (MMR) (52.9% versus 32%) and a shorter time to MMR, 22 months (range 5-70) versus 35 months (range 8-53). OCML experienced more haematological and non-haematological treatment-related adverse events after imatinib therapy. Conclusion: Although OCML patients had more comorbidities and treatment intolerances, overall long-term treatment response was comparable to YCML. In OCML, a more personalised approach to initial and subsequent dosing of imatinib may be considered.

Discordant lymphoma (DL) is the coexistence of two or more distinct subtypes in separate anatomic sites. There are limited reports on DL cases especially involving more than two subtypes in more than two sites. We report a 76-year-old man who presented with constitutional symptoms, flank mass and painless lymphadenopathies for six months. Laboratory tests revealed moderate anaemia, markedly elevated serum IgM (13400 mg/dL), IgM Lambda paraproteinemia and Lambda light chain paraproteinuria with unmeasurable serum lactate dehydrogenase due to hyperviscous sample. CT scan showed multiple subcutaneous masses over chest wall and retroperitoneum, with lytic bone lesions, and hepatosplenomegaly. Further biopsy findings with morphological, immunohistochemical and molecular analysis of the tissue sections revealed diffuse large B-Cell lymphoma in the chest wall mass, follicular lymphoma in the inguinal lymph node and lymphoplasmacytic lymphoma in the bone marrow. This case highlights the rare DL. The importance of histopathological evaluation of lymphoma despite the availability of PET-CT scans for disease staging is undeniable.