Abstract 1191P
Background
Thyroid transcription factor-1 (TTF-1), is expressed in thyroid and lung tissue. TTF-1, assessed by immunohistochemistry (IHC), is a specific biomarker for lung adenocarcinoma, and is commonly used to confirm the pulmonary origin of neuroendocrine tumors (NET), as well. The majority of the available data suggest that TTF-1 is a favourable prognostic biomarker for lung adenocarcinomas, whereas its role in lung NET is controversial.
Methods
A multicenter retrospective study, including 155 Lung NET, all surgically removed, all with available IHC assessment for TTF-1.
Results
Median age was 59.5 years (13–86), N= 58 patients (37.4%) were males, N=40 (25.8%) were smokers, N=31 (20%) were atypical carcinoids, N=85 (54.8%) were centrally-located, N=89 (57.4%) were located in the right lung, N=4 patients (2.6%) presented a TNM stage IV at the diagnosis. Mitotic count was ≥2 per 10 high-power field (HPF) in N=35 cases (22.6%), necrosis was present in N=20 (12.9%). Grade 1 was reported in 103 cases (66.5%), whereas Ki-67 was >20% in N=5 (3.2%). TTF-1 was positive in 78 cases (50.3%), cromogranin A in 139 (89.7%) and synaptophysin in 137 (88.4%), respectively. The most common type of surgery was lobectomy in 91 patients (58.7%). Median overall survival (OS) was 46.9 months (0.6–323), median progression-free survival (PFS) was 39.1 months (0.6–323). Statistically significant associations were found between (i) TTF-1 positivity and female sex (p=0.007), and among (ii) TTF-1 positivity and the absence of necrosis (p=0.018). No other relevant associations were detected between TTF-1 and the remaining clinical or pathological variables.
Conclusions
This study highlights that TTF-1 positivity differs according to sex in lung NET patients, with a more common TTF-1 positive staining in female. Moreover, TTF-1 was associated with the absence of necrosis. These data suggest that TTF-1 could potentially represent a gender-related biomarker in this population. Further analyses are needed to establish the value of this observation, and to determine the value of TTF-1 as prognostic biomarker for lung NET.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
1159P - Characterization of melanoma of unknown primary in the era of immunotherapy and targeted therapy in Spain: Results from the prospective real-world study GEM 1801
Presenter: Pablo Cerezuela-Fuentes
Session: Poster session 13
1160P - Methods of nivolumab administration in advanced melanoma: A comparison of patients’ clinical outcomes treated with flat dose or weight-adjusted dose, FLATIMEL study
Presenter: Iona Campo le Brun
Session: Poster session 13
1161P - Therapeutic outcome of molecular profiling of melanoma patients resistant to standard treatment: Real-world data
Presenter: Madona SAKKAL
Session: Poster session 13
1162P - Prolonged exposure to proton pump inhibitors (PPI) at the time of initiation of immune checkpoint blockade (ICB) mediates better clinical outcomes in patients with metastatic melanoma
Presenter: Kyrillus Shohdy
Session: Poster session 13
1163P - CD39 affect the prognostic role of NLR via N2 neutrophils in metastatic melanoma patients treated with immunotherapy
Presenter: Domenico Mallardo
Session: Poster session 13
1164P - Changes of TCR repertoire in metastatic melanoma and renal cell carcinoma patients treated with nivolumab correlate with overall survival
Presenter: Martin Klabusay
Session: Poster session 13
1165P - Single cell spatial features of in-transit melanoma associated with patient outcome to immunotherapy
Presenter: Xinyu Bai
Session: Poster session 13
1166P - Multi-modal and longitudinal characterization of the tumor and immune microenvironment from primary melanoma to in-transit and distant metastasis
Presenter: Giuseppe Tarantino
Session: Poster session 13
1168P - Tumor PD-L1 predicts the outcome of PD-1-based immunotherapy in metastatic melanoma depending on the type of tissue examined
Presenter: Jan-Malte Placke
Session: Poster session 13
1169P - Tumour transcriptional and spatial protein profiling in Mexican patients reveals that acral lentiginous melanoma is characterized by an immunosuppressive microenvironment
Presenter: Martha Estefania Vázquez-Cruz
Session: Poster session 13