Effect of clinical and pathological features of gastrointestinal stromal tumors on overall survival and prognosis: Single center experience

Aim

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. We aimed to evaluate the clinicopathological features of the patients in Thrace and improve our management.

Material and Method

In this retrospective study, 68 patients with a diagnosis of GIST referred to Trakya University Medical School Hospital between 1997 and 2015 were evaluated.

Results

The most common symptom was abdominal pain (38.2%) and the location was small-intestine (42.6%). Large masses had higher metastasis and relapse rate. The mean tumor size with relapse was 11.8 ± 3.8 cm meanwhile it was 6.5 ± 3.0 cm in non-relapsed patients (p = 0.01). The mean size of the tumor was 13.5 ± 4.4 in the metastatic group although this data was 8.8 ± 4.7 cm in the non-metastatic group (p = 0.01). With necrotic tumors, mitotic rate and size were higher. The mean mitosis count was 21.0 ± 3.6 in necrotic tumors and 7.2 ± 9.9 in non-necrotic tumors (p = 0.005). The mean size was 10.8 ± 5.0 cm in necrotic tumors and 5.6 ± 3.0 cm in non-necrotic tumors (p = 0.009). According to AFIP criteria, most of the patients were in the high-risk group (57.4%). Overall survival (OS) was longer in non-smokers and non-drinkers. Median OS was 80.16 months in non-smoker group (95% CI, 27.83–132.49) and 24.64 months (95% CI, 15.49–33.78) in the smoker group (p = 0.001). The median OS was 80.09 months in the non-drinker group (95% CI, 13.99–146.20) and 24.64 months (95% CI, 13.18–36.10) in drinker group (p = 0.05). Median OS in stomach GIST was 41.39 months, in small-intestine were 80.09 months and in the colon were 35.68 months (p = 0.032). Patients underwent surgery had longer overall-survival. Median OS was 80.09 months in patients undergone surgery and 16.98 months in patients had not been operated (p = 0.001). Overall survival was longer in GIST with mitotic rate <5/50HPF than with >5/50HPF. Median OS was 80.16 months in patients who had less than 5 mitosis and 39.22 months in higher mitotic rate (95% CI, 31.58–46.87) (p = 0.034). Overall survival was shorter in GIST with Ki-67 > 5% than with 5%>. Median OS was 80.16 months (95% CI, 28.80–49.65) in <5% and 39.22 months (95% CI, 28.80–49.65) in 5%≤ Ki-67 (p = 0.004).

Conclusions

The most important factors about the survival and prognosis of GIST are location, size, mitotic rate, Ki-67, necrosis and surgery status. Using tobacco/alcohol may be related to survival. This study should be further investigated with extensive data.