A 17-year-old female, without medical history, presented with a 15-day history of diplopia, nasal obstruction, and left orbital pain, associated with fever and night sweats. The physical examination found a left exophthalmos and bilateral cervical lymphadenopathy. T2-weighted orbital magnetic resonance imaging showed a left soft-tissue mass slightly hyperintense compared to muscle involving intra- and extraconal space responsible for an exophthalmos, with an extension to the left ethmoid sinus and the left nasal fossa. Biopsy of the nasal mass and histopathologic examination objectified a high-grade DLBCL (CD20+, Bcl2+, CD3-, and CD5-, with a Ki-67 proliferation index of 95%). In addition, the cerebrospinal fluid analysis was consistent with a central nervous system (CNS) involvement.\nBaseline18F-FDG PET/CT revealed intense18F-FDG uptake throughout the bilaterally enlarged renal parenchyma, on the soft tissue in the left orbit extending into the left nasal cavity, and on cervical and abdominal lymph nodes. Peritoneal nodules with diffusely increased18F-FDG and multiple hypermetabolic bones foci, including humeri, ribs, and pelvis uptake were also noted []. After 4 cycles of dose-adjusted EPOCH-rituximab, the patient was referred for18F-FDG PET/CT for response evaluation. The18F-FDG PET/ CT showed a total regression of renal lesions suggesting good response to therapy [].
A 50-year-old female with a past medical history significant for idiopathic thrombocytopenic purpura (ITP) presented with chief complaint of back pain for three weeks. Prior to her presentation, the patient was undergoing treatment for ITP wherein she had received four doses of weekly rituximab and recently completed a prednisone taper. A computed tomography (CT) scan of the abdomen and pelvis showed bilateral renal masses (6.6 x 4.2 cm on the right, 6.3 x 5 cm on the left) with upper para-aortic and right retro-crural lymphadenopathy (Figure ). Upon chart review, it was noted that the abdominal ultrasound done seven months prior to admission (for thrombocytopenia workup) was negative for renal masses. She was admitted for evaluation; laboratory workup showed white blood cell count 10.55 TH/uL, hemoglobin 12.3 g/dL, and platelet count 113 TH/uL. Her kidney function and liver function tests were normal. Lactate dehydrogenase was elevated at 763 IU/L (range 313-618). A CT guided biopsy of the left renal mass showed DLBL (Epstein-Barr virus (EBV) negative, fluorescent in situ hybridization (FISH) negative for MYC rearrangement, but 71% of interphase cells showed three copies of an intact MYC (8q24.1), 65% positive for rearrangement of BCL6, no BCL2 fusion). Bone marrow biopsy and flow cytometry were negative. Positron emission tomography (PET)/CT showed left supraclavicular and retroperitoneal lymphadenopathy (standardized uptake values (SUV) 10.8 and 15.7 respectively) with hypermetabolic bilateral renal masses (SUV 15.3 and 17.5 on right and left respectively) (Figure ). Lumbar puncture cytology was negative. Given these findings, she was staged IVB and received intrathecal methotrexate for central nervous system (CNS) disease prevention. The next day, the patient was started on dose-adjusted rituximab, etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin (DA-REPOCH) chemotherapy regimen. She completed six cycles of DA-REPOCH and intrathecal methotrexate with no evidence of disease on repeat imaging (Figure ). She continues to follow up with oncology clinic for observation and is in complete remission at one year.