The study analyzed the characteristics of 1624 inpatients with STS excluding visceral sarcoma from Henan Province Cancer Hospital from 2006 to 2016. We found that the top nine were UPS (accounting for 23.83% all STS), synovial sarcoma (16.69%), liposarcoma (13.67%), fibrosarcoma, sarcoma without definite type, leiomyosarcoma, dermatofibrosarcoma protuberant, rhabdomyosarcoma, and malignant peripheral nerve sheath tumor. The number of inpatients with STS in the first three pathological types accounted for 54.19% of all the inpatients with STS in Henan Province Cancer Hospital. The first three pathological types of over 45 years old STS inpatients in Beijing were UPS(19.22%), liposarcoma (19.04%) and malignant peripheral nerve sheath tumor (10.18%)[7], the first three pathological subtypes of STSs in Taiwan were liposarcoma(23%), UPS(18.9%) and leiomyosarcoma(7.6%)[8],and the first three pathological types of STSs in Japan were UPS(19.46%), well differentiated liposarcoma(19.23%), myxoid/round cell liposarcoma (9.35%)[9].Three results were different from ours. By contrast, Fang’s[10] research was consistent with ours. He analyzed information of 1118 patients with STS, and found that the most common first three pathological types were UPS(35.24%), synovial sarcoma (17.08%) and liposarcoma (16.28%).We speculated that the difference may be due to different data collection methods, because the research in Beijing, Taiwan and Japan was population-based incidence data, and the analysis of STS in Beijing was divided into three age groups: 0–14 years old, 15~44 years old and over 45 years old, in which the first three pathological types were analyzed in the group of over 45 years old. Particularly, It was noteworthy that synovial sarcoma was the most common diagnosis in foot and ankle malignant soft tissue tumors[11].
Previous studies have shown that the median age of inpatients with STS was 59 years old[12]. The study showed that the average age of inpatients with STS in Henan Province Cancer Hospital was 44.71±17.91 years old, and the peak age of onset was 40–59 years old. Morever, the median age of inpatients with STS has been postponed from 43 years old in 2006 to 51 years old in 2016, which may be related to population aging. However, the peak age of STS in Beijing was 80–84 years old[7], which may be related to the grouping method. The lower peak age in the study may be related to it including embryonal rhabdomyosarcoma with the lower age of onset. The peak age of STS of the extremities in Korea from 2009 to 2011 was 70–89 years old[13], and the peak age of STS in Ireland from 1994 to 2012 was 70–84 years old[14], which were different from the results of the study. The reason may be that the result in Korea mainly studies STS of the extremities, but not the whole body (excluding visceral sarcoma), and the research in Ireland was about the whole body including visceral sarcoma. While in our study, we mainly analyze whole body STS, visceral sarcoma excluded.
We found that the median age of inpatients with UPS was delayed by 10 years old by analyzing the proportion in the first nine pathology subtypes during the period of 2006 to 2016, and UPS accounted for almost 35% of all inpatients with STS at the age of over 55, which suggested that the important age boundary of UPS was 55 years old. In addition, the present study and published studies manifested that synovial sarcoma was more frequently diagnosed in young patients over 15 years old, which was associated with the comliex nature of synovial sarcoma[15, 16]. Meanwhile, we speculated that onset age of malignant peripheral nerve sheath tumor tend to be younger according to the median age of inpatients with malignant peripheral nerve sheath tumor was about 10 years old younger in the study, therefore, we can further speculate that the incidence of malignant nerve sheath tumor with neurofibromatosis type 1 (NF1) may be higher in all subtypes in the future, because the age of onset of NF1was younger[17, 18]. Rhabdomyosarcoma was the most common subtype of STS under the age of 20, accounting for 36.67%.The high incidence of different pathological subtypes in all age groups suggested that we need to explore it’s possible risk factors in future studies.
We analyzed the gender distribution of STS in Henan Province Cancer Hospital from 2006 to 2016, and found that among 1624 inpatients including 923 males and 701 females, and the ratio of male to female was 1.32:1.Lei Y[7] et al found that the incidence of STS of males in Beijing was higher than that of females, and the incidence rate of both males and females was 1.38:1 on the basis of population-based STS data from 1999 to 2013 collected by the Beijing Cancer Registry. The result was similar with Taiwan, where the gender ratio was 1.34:1[8]. These were similar to the situation in Henan province. However, the STS surveillance data from 27 countries in Europe showed that the female incidence rate was 5.0/100,000, the male incidence rate was 4.4/100,000, and the female was slightly higher than the male[19]. We hypothesized that the reason was that they included data on internal organs. The incidence of uterine leiomyosarcoma and mammary sarcoma in women was significantly higher than that of epididymis sarcoma in male, and the visceral sarcoma data was included in this study, so the incidence of STS in women was higher. In contrast, visceral sarcoma was not included in the study.
In short, we analyzed the sex, age, pathological subtypes of STS and their change trends in 1624 inpatients with soft tissue sarcomas (excluding visceral organs) from Henan Province Cancer Hospital from 2006 to 2016 in the study. We have a clearer understanding of the basic situation and epidemiological trends of STS in Henan province represented by Henan Province Cancer Hospital, and point out the direction for the prevention and treatment of STS in the future.