Abstract
Objectives: To characterize the incidence proportions and
survival probability of patients with hypo-pharyngeal cancer and lung
metastases.
Design: Secondary data analysis
Setting: The Surveillance, Epidemiology, and End Results (SEER)
database of the National Cancer Institute.
Participants: We identified 2814 adult patients diagnosed with
hypo-pharyngeal cancer between 2010 and 2014 for whom the status of lung
metastases was known. Patients with an unknown follow-up were excluded;
leaving 2714 patients in this cohort.
Main outcome measures: Multivariable logistic and Cox
regression models were performed to identify the risk factors associated
with the presence of lung metastases at diagnosis and five-year
all-cause mortality respectively.
Results: We identified 128 patients with lung metastases at the
time of diagnosis of hypo-pharyngeal cancer, representing 4.7% of the
entire cohort. Females were less likely to have lung metastases (15,
11.7%)(P =0.037). Incidences of lung metastases was higher among
patients with histological grade III/IV (56,
43.8%)(P <0.001). Patients with lung metastases had a
larger tumor size(49.96\(\pm\)90.25mm, P <0.001). For
each 10 mm increase in tumor size, the odds of having lung metastases
increased by 6.6%. Patients with lung metastases had a shorter survival
time(HR:3.05, 95% CI:2.17-4.28, P <0.001). For age,
tumor size increase and black study subjects were also significantly
associated with a shorter survival time.
Conclusion: Our study provides insight into the epidemiology of
lung metastases in patients with hypo-pharyngeal cancer. When the tumor
is diagnosed, we should pay close attention to the sex, race, tumor size
and histological grade in order to quickly detect the distant
metastases.
Key Words: hypo-pharyngeal cancer; lung metastases; SEER