EBV-Negative Cutaneous Lymphomatoid Granulomatosis With Concomitant EBV-Positive Pulmonary Involvement

The Role and Pitfall of F18-FDG PET/CT in Surveillance of High Grade Pulmonary Lymphomatoid Granulomatosis

Lymphomatoid granulomatosis (LYG) is an uncommon angiocentric and angiodestructive T-cell rich, Epstein-Barr virus (EBV) positive B-cell multisystem lymphoproliferative disorder, predominately affecting the lungs. Since both clinical presentation and radiographic imaging findings, including X-ray and computed tomographic (CT), are nonspecific, the ultimate diagnosis of LYG relies on lung tissue sample diagnosis with its WHO grading based on the degree of cytologic atypia, necrosis and density of EBV positive B-cells. In addition, its histopathologic grading is correlated with clinical manifestation with high grade LYG mimicking aggressive B-cell lymphoma. Discordant grading between pulmonary and cutaneous LYG lesion has have been observed and might be a potential diagnostic and prognostic pitfall. F18-FDG PET/CT has been used to monitor disease progression and treatment response. In this study, we reviewed and summarized the clinical role of F18-FDG PET/CT in the surveillance of high grade pulmonary LYG, and examined its limitations in grading multisystem LYG.

Pitfall of 18F-FDG PET/CT in Characterization of Relapsed Multisystem Lymphomatoid Granulomatosis

We present serial ¹⁸F-FDG PET/CT findings in a case of grade 3 pulmonary lymphomatoid granulomatosis positive for the Epstein-Barr virus. The patient experienced a transient complete response to R-CHOP chemotherapy and subsequent multisystem recurrence, predominately involving the subcutaneous region of the torso on ¹⁸F-FDG PET/CT. Biopsy of the most hypermetabolic subcutaneous lesion demonstrated grade 1 cutaneous lymphomatoid granulomatosis negative for the Epstein-Barr virus. This report highlights the role of ¹⁸F-FDG PET/CT in characterizing and monitoring disease progression and regression, as well as the limitations of ¹⁸F-FDG PET/CT in accurate grading of multisystem recurrence, given the diversity of clinical and histopathologic features of lymphomatoid granulomatosis.

Recent Advances in Aggressive Large B-cell Lymphomas: A Comprehensive Review

Diffuse large B-cell lymphoma (DLBCL) is an aggressive disease with considerable heterogeneity reflected in the 2008 World Health Organization classification. In recent years, genome-wide assessment of genetic and epigenetic alterations has shed light upon distinct molecular subsets linked to dysregulation of specific genes or pathways. Besides fostering our knowledge regarding the molecular complexity of DLBCL types, these studies have unraveled previously unappreciated genetic lesions, which may be exploited for prognostic and therapeutic purposes. Following the last World Health Organization classification, we have witnessed the emergence of new variants of specific DLBCL entities, such as CD30 DLBCL, human immunodeficiency virus-related and age-related variants of plasmablastic lymphoma, and EBV DLBCL arising in young patients. In this review, we will present an update on the clinical, pathologic, and molecular features of DLBCL incorporating recently gained information with respect to their pathobiology and prognosis. We will emphasize the distinctive features of newly described or emerging variants and highlight advances in our understanding of entities presenting a diagnostic challenge, such as T-cell/histiocyte-rich large B-cell lmphoma and unclassifiable large B-cell lymphomas. Furthermore, we will discuss recent advances in the genomic characterization of DLBCL, as they may relate to prognostication and tailored therapeutic intervention. The information presented in this review derives from English language publications appearing in PubMed throughout December 2015. For a complete outline of this paper, please visit: http://links.lww.com/PAP/A12.