[Clinical analysis of 33 cases of primary pulmonary NUT carcinoma]

Objectives: Cases from our hospital and a systematic review were performed in this paper to get a better understanding on the diagnosis and therapies for primary pulmonary NUT carcinoma (PPNC) patients. Methods: The clinical features, pathological diagnosis, treatment and outcomes of PPNC patients from 2020-2025, including four cases from the First Affiliated Hospital of Soochow University, were collected delicately. The Kaplan-Meier method and Cox proportional hazard regression model were used to calculate cumulative survival and prognostic factors. Results: The male-to-female ratio of PPNC was 18∶15, the left to right ratio was 14∶19, the median age was 36 years old and the median tumor diameter was 6.1 cm. Most patients were already at an advanced stage with the clinical features-cough (16/33) and chest or back pain (13/33) when they first came to the hospital. The tumor cells were arranged in nest pattern with small-medium size, round to oval shape, and nuclei were deeply stained. The high positive staining of NUT (32/32) and CK-pan (16/19) was observed, NUTM1 gene translocation in 24 cases was detected by fluorescence in situ hybridization (FISH), and different gene rearrangements were located by NGS-NUTM1-BRD4 (8/12), NUTM1-BRD3 (2/12), NUTM1-BRD2 (1/12) and NUTM1-ZNF532 (1/12). Most patients accepted different chemotherapy regimens (25/29), including paclitaxel albumin and platinum (13/25), etoposide and platinum (8/25). Meanwhile, 12 cases were treated with PD-1/PD-L1 antibody during the therapy. The median follow-up time was 7 months in 28 cases tracked from 2-90 months. Univariate Cox regression analysis showed that metastasis of this disease affected patient prognosis (HR=2.55, 95% CI: 0.974-6.677, P=0.057) and the cumulative survival rate was lower in the older ones. Conclusions: PPNC, more often found in middle-aged patients, no difference in sex, can be diagnosed by pathmorphology and immunophenotype, while NUTM1 molecular test is highly suggested for the accurate therapy. Metastasis can be recognized as the prognostic risk factor. Early detection of the cancer improves the chances of successful treatment, especially in patients with older age.