BACKGROUND: Patients with autoimmune conditions receiving immunosuppressants are at risk of non-Hodgkin lymphomas (NHL). Vedolizumab (anti-α4β7-integrin antibody), a treatment-of-choice for Crohn\'s disease (CD), reduces inflammatory lymphocyte trafficking into the intestinal mucosa. This effect is believed to be confined to the colon.
METHODS: We report the case of a CD patient on vedolizumab for five years who developed pediatric-type follicular lymphoma. Work-up prior to therapy revealed a reduction in circulating T-lymphocytes and their suppressed response to mitogens. Rituximab, cyclophosphamide, vincristine, and prednisone chemo-immunotherapy resulted in durable lymphoma remission, and vedolizumab treatment was continued. While the patient\'s T-lymphocyte population and immunoglobulin production recovered, the T-lymphocyte mitogen response remained suppressed.
CONCLUSIONS: This patient\'s NHL may be linked to receiving anti-α4β7 therapy. Further research could be beneficial to determine if proactive surveillance for NHL and other systemic diseases is indicated in patients on vedolizumab.

Pediatric-type follicular lymphoma is a disease that affects the lymph nodes of the head and neck in the adult and pediatric patient groups. Ocular involvement is exceedingly rare, especially in the pediatrics age group; therefore, keeping a high clinical suspicion is warranted. Here, we report a rare conjunctival pediatric-type follicular lymphoma in a 15-year-old boy presenting with progressive swelling over the medial aspect of the left bulbar conjunctiva for two months. On examination, the mass was firm, mobile, well encapsulated, wide-based, and had a negative transillumination. An excisional biopsy was performed, and histopathological examination and immunohistochemistry studies revealed lymphoid tissue that was positive for CD20, CD79a, BCL6, and CD10; and negative for BCL2 and MUM1. The CD21 and CD23 positivity highlighted the presence of an expanded follicular dendritic cell meshwork. The patient was diagnosed with conjunctival pediatric-type follicular lymphoma and referred to an oncology center for further examination and treatment. This lymphoma is rare, requiring high clinical suspicion, and thus, reporting the case detail is important and valuable for ophthalmologists and general pediatrics practitioners alike.

BACKGROUND: Pediatric-type follicular lymphoma (PTFL) is a unique pathological type in the 4th edition of hematopoiesis and lymphoid tissue tumor classification revised by World Health Organization. It is unique in clinical practice and seldom seen in adult. PTFL mainly occurs in the head and neck lymph nodes. Most of the cases are short of fever, night sweat, weight loss, and other B symptoms which substitute for lymphadenopathy as the main symptom. PTFL can be disposed of surgical resection and it can achieve long-term tumor-free survival, and it has an excellent outcome.
METHODS: Two cases of PTFL were reported and their clinicopathological features, differential diagnosis, therapy and prognosis were discussed. PTFL showed gray-brown tough texture in general performance. The histological manifestations of PTFL were similar to that of adult-follicular lymphoma (FL). Under low power microscope, the structure of lymph nodes was destroyed in different degree, the follicles were closely arranged, expanded and irregular, and the mantle zone became thin or disappeared. In addition, the \"starry sky phenomenon\" could be seen. At high magnification, the follicles were mainly composed of single medium-sized central cells, and some of them mainly consisted of centroblastic cells to characterize scattered chromatin and inconspicuous nucleoli. Immunohistochemical showed the tumor cells expressed CD20, PAX5, CD79a and CD10, BCL6, FOXP-1, which were limited in germinal center; Ki-67 was highly expressed in germinal center. CD21 and CD23 showed nodular and expanded follicular dendritic cells. Immunoglobulin gene rearrangement was positive for IGH and IGK. The two patients underwent surgical resection with no complications. After discharge, the two patients with a close review for 18 mo and 5 mo respectively and showed no evidence of recurrence.
CONCLUSIONS: PTFL in adult is generally supposed to be extremely rare. PTFL displayed characteristic morphological, immunophenotypic, and molecular biological changes which are a kind of neoplasm with satisfactory prognosis after surgical excision.

Pediatric-type follicular lymphomas are rare lymphomas, affecting mostly children and young adults. These are characterized by an excellent prognosis, despite their conservative therapeutic approach. Recognized as an entity in the most recent 2016 WHO classification of tumors of hematopoietic and lymphoid tissues, its diagnosis is based on the recognition of an exclusively nodular architecture, thus conditioning the possibility of a cytological diagnosis. It is thus not odd, the scant literature found on the cytological approach to these lesions. Herein we describe a case of a pediatric-type follicular lymphoma, first approached through fine needle biopsy. The case is thoroughly discussed from a cytologic, immunophenotypic, and molecular point of view. Differential diagnoses are discussed. The final diagnosis was performed on histology.

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a relatively common tumor of the central nervous system. Although PCNSLs generally arise from the parenchyma, lymphomas arising primarily from the dura are termed dural lymphomas (DLs). Mucosa-associated lymphoid tissue is the most unique histological feature of DLs. Because of its rarity, the clinical characteristics of and treatments for DL have not been fully elucidated to date.
METHODS: A 31-year-old man with no past medical history presented with numbness in his left upper limb. Magnetic resonance imaging revealed a dural-based tumoral lesion and cervical lymphadenopathies. The lesion was diagnosed radiologically as a meningioma, and tumor resection was planned. However, an intraoperative pathological diagnosis showed neoplastic lymphocytes, and the planned total tumor resection was halted. Histologically, the tumor was characterized by areas of poorly defined follicular architecture consisting of medium and large centroblasts. These tumor cells were immunohistologically positive for CD10 and CD20 and negative for B-cell lymphoma (BCL) 2 and BCL6. Fluorescence in situ hybridization did not show evidence of an Immunoglobulin H/BCL2 fusion. The lesion was subsequently diagnosed as a pediatric-type follicular lymphoma (PTFL). Six cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) plus 2 cycles of rituximab were administered. The patient showed no evidence of relapse at 12 months after diagnosis, and follow-up was ongoing at the time of this report.
CONCLUSIONS: This very rare case of DL was originally diagnosed as a PTFL. The tumor could be treated by immunochemotherapy alone.