There is increasing use of MMF for the prevention and treatment of acute GVHD. Although direct comparative data is limited, there is an expectation that this drug has significant activity and a favorable toxicity profile compared to other immunosuppressive therapies for GVHD. However, the pharmacokinetics have not been well defined in this setting. This analysis from Jacobson and colleagues for the BMT-CTN is important since it shows that obtaining therapeutic levels is important to optimize response rates for acute GVHD without resulting in increased risk of infection or limited survival at least by day 180. This should directly impact how transplant physicians use MMF. Further pharmacokinetic studies will be needed to define the optimal dose and schedule, but consideration should be given to either close drug monitoring and/or altering dosing from 2 to 3 g/day or body weight dosing. Primary pulmonary non-Hodgkin's lymphoma (PPL) is a rare extranodal lymphoid neoplasm. The present knowledge of this entity is vague and minimal. A total of 29 patients diagnosed with PPL at Sun Yat-Sen University Cancer Center in China were retrospectively analyzed. Nineteen patients had mucosa-associated lymphoid tissue (MALT) lymphoma, nine had diffuse large B-cell lymphoma (DLBCL), and one had plasmacytic lymphoma. Six patients received PET/CT scans before treatment, and mean maximum standardized uptake values (mSUVs) were much higher in the DLBCL cases (n 5 3) than in the MALT lymphoma cases (n 5 3). The 3-year overall survival (OS) rate was 79.3%. Cox regression analysis showed that hilar/mediastinal lymphadenopathy (LAP) was an independent predictor of survival (P 5 0.029). The mean survival time (MST) was 75.5 months for patients who underwent surgery and 65.7 months for those who didn't (P 5 0.38). The MST was 77.4 months for patients treated with rituximab and 54.1 months for those not treated with rituximab (P 5 0.101). Clinical characteristics in our study were partly similar to those previously reported. However, we found that hilar/mediastinal LAP seemed to be an effective prognostic factor in Chinese PPL patients. The role of surgery and rituximab in the management of PPL warrants further investigation. PPL is quite rare and it is defined as clonal lymphoid proliferation involving the lung parenchyma and/or bronchi but without extrathoracic extension at the time of diagnosis or within the subsequent 3 months [1, 2] . Patients diagnosed with PPL may present with hilar or mediastinal LAP, but most of the tumor burden is in the lung [1] . PPL represents only 0.4% of all lymphomas, and less than 1% of NHL [2] [3] [4] . The treatment for primary pulmonary lymphomas (whether surgery, radiotherapy, chemotherapy, or targeted therapy alone or in combination) has not been clearly established. The role of rituximab in the treatment of PPL remains controversial [5] .