Clinicopathologic Correlates of PIT1 and SF1-Multilineage Pituitary Neuroendocrine Tumors and the Diagnostic Utility of NKX2.2 Immunohistochemistry in Pituitary Pathology


DOĞUKAN F. M., KARATAY H., Yüzkan S., Burhan Ş., Erkan B., Yilmaz-Özgüven B.

Archives of Pathology and Laboratory Medicine, cilt.149, sa.1, ss.83-89, 2025 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 149 Sayı: 1
  • Basım Tarihi: 2025
  • Doi Numarası: 10.5858/arpa.2023-0543-oa
  • Dergi Adı: Archives of Pathology and Laboratory Medicine
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, CINAHL, MEDLINE, Public Affairs Index
  • Sayfa Sayıları: ss.83-89
  • Sağlık Bilimleri Üniversitesi Adresli: Evet

Özet

Context. - PIT1 and SF1-multilineage pituitary neuroendocrine tumors (PitNETs) have been defined since the classification of adenohypophysial tumors based on the PIT1, SF1, and TPIT transcription factors. Objective. - To describe the clinicopathologic features of PIT1 and SF1-multilineage PitNETs and to contribute to the pituitary pathology practice by questioning the expression of NKX2.2 in PitNETs. Design. - We reviewed 345 PitNETs and described the clinicopathologic features of 8 PIT1 and SF1-multilineage tumors. NKX2.2 positivity and staining pattern were compared to those of 45 PitNETs from the control group. Results. - PIT1 and SF1-multilineage PitNET patients had a mean age of 41.13 (range, 14-58 years) and a mean tumor diameter of 14.0 mm (range, 8-20 mm). The most common clinical presentation was acromegaly (6 of 8), and postoperative remission was achieved in all patients. On histomorphologic examination, a pseudopapillary pattern was seen in 5 of the tumors, either focally or diffusely. In addition to PIT1 and SF1, there was a diffuse staining with growth hormone and a predominantly perinuclear staining with cytokeratin 18. With NKX2.2, all multilineage tumors were positive, of which 5 were diffuse and 3 were focal. In the control group, 8 tumors (8 of 45) were positive, of which only 1 was diffuse and 7 were focal. Conclusions. - In conclusion, NKX2.2 is a transcription factor that can be used as an additional tool in pituitary pathology, and PIT1 and SF1-multilineage PitNETs are specific tumors that usually present with acromegaly, show signs of a nonaggressive clinical course, have a pseudopapillary histomorphology, and express NKX2.2.