INTERNATIONAL GEVHER NESIBE HEALTH SCIENCES CONFERENCE-VI , Ankara, Turkey, 13 - 15 November 2020, pp.313-314
Introduction: Diagnosis of in situ follicular neoplasia (ISFN) limited in the physiological compartment of
germinal centers is difficult, histopathologically. However, it is accepted as the early phase of lymphogenesis
and/or premalignant according to recent clinical and molecular studies.
INTERNATIONAL GEVHER NESİBE HEALTH SCIENCES CONFERENCE-VI/ November 13-15, 2020 Ankara/ Proceedings Book
Objective: It was aimed to discuss the histopathological features of ISFN. We targeted to investigate which
criteria should be considered in case selection for immunohistochemical studies. In addition, the importance
of diagnosis in the clinical process was tried to be interpreted.
Material-Method: Between 2014-2019, hematoxylin-eosin sections and CD10, Bcl2, ki67 stained
immunohistochemistry slides of seven lymph node excisions diagnosed with ISFN were re-evaluated,
retrospectively. Clinical informations were obtained from the hospital information system.
Results: Four of the cases were female and three were male. The average age is 49.17. The average of the
largest diameters of lymph nodes was 2.07 cm. Four of the cases presented with the complaint of
cervical/axillary swelling. Lymph nodes were detected incidentally in three cases. The architecture was
preserved in all lymph node sections. Atypical follicles were randomly scattered and had strong expression by
CD10 and Bcl2. No polarization was seen in ki67 staining. Germinal centers were of normal size, cytology
was monotonous. Tingible body macrophages were absent or decreased. The number of neoplastic cells in
atypical follicles was variable. Similar histopathological features were observed in the re-biopsy (in 2019) of
the case in which ISFN and hyaline vascular Castleman-like changes were detected in 2014. Lymphoma
development was not detected in any of the cases.
Conclusion: In situ follicular neoplasia cases, in which it is difficult to determine the true incidence due to its
subclinical nature, can be diagnosed infrequently. Histopathological diagnosis, in which the use of
immunohistochemistry is essential, is a concern for pathologists. The fact that there was no progression to
lymphoma in our case group is partially soothing.
Keywords: Lymphoma, Follicular; Neoplasia; CD10; Bcl2; Ki67