Solitary Fibrous Tumors of Chest: Another Look with the Oncologic Perspective

Solitary fibrous tumors are mesenchymal lesions that arise at a variety of sites, most commonly the pleura. Most patients are asymptomatic at diagnosis, with lesions being detected incidentally. Nevertheless, some patients present due to symptoms from local tumor compression (eg. of the airways and pulmonary parenchyma). Furthermore, radiological methods are not always conclusive in making a diagnosis, and thus, pathological analysis is often required. In the past three decades, immunohistochemical techniques have provided a gold standard in solitary fibrous tumor diagnosis. The signature marker of solitary fibrous tumor is the presence of the NAB2-STAT6 fusion that can be reliably detected with a STAT6 antibody. While solitary fibrous tumors are most often benign, they can be malignant in 10-20% of the cases. Unfortunately, histological parameters are not always predictive of benign vs malignant solitary fibrous tumors. As solitary fibrous tumors are generally regarded as relatively chemoresistant tumors; treatment is often limited to localized treatment modalities. The optimal treatment of solitary fibrous tumors appears to be complete surgical resection for both primary and local recurrent disease. However, in cases of suboptimal resection, large disease burden, or advanced recurrence, a multidisciplinary approach may be preferable. Specifically, radiotherapy for inoperable local disease can provide palliation/shrinkage. Given their sometimes -unpredictable and often- protracted clinical course, long-term follow-up post-resection is recommended

The analysis of clinical and dosimetric factors associated with side effects and survival in patients with non-small cell lung cancer treated by definitive three-dimensional conformal radiotherapy (3D-CRT)± concomitant chemotherapy

2009-2012 arasında üç boyutlu konformal teknikle definitif radyoterapi (3DCRT) ± eşzamanlı kemoterapi (KT) uygulanmış ve en az 6 ay yaşayan küçük hücreli dışı akciğer kanserli olgular incelendi. Toplam doz, biyolojik efektif doz (BED) eşdeğerine dönüştürülerek normal doku komplikasyon olasılığı (NTCP) hesaplandı. İstatistiki analiz Şubat 2013?te SPSS v.20 ile uygulandı. Medyan yaş 59 (aralık 36-81) olup bloklu konformal (n: 37), 3DCRT (n: 11) ve yoğunluk ayarlı RT (IMRT) (n: 20) ile medyan 63 Gy (aralık: 54-70 Gy) uygulandı. Neoadjuvan, eşzamanlı, adjuvan KT sırasıyla; 29, 49, 41 olguda verildi. Akut grad (G) 1-3 özafajit, akut G1-2 radyasyon pnömonisi (RP), radyasyon fibrozisi sırasıyla; %48, %13, %18 oranında gelişti. Tedavi şekli, RT dozu, tümör BED, dozimetrik faktörler ve KT ile RP arasında anlamlı ilişki gösterilemedi (p >0,05). Fizik ve biyolojik mean akciğer dozu (MLD) arasında iyi bir korelasyon vardı (0,93). Medyan MLD 17 Gy, MLDbiyo 16,7 Gy, V30 %20,5, NTCP 0,142 bulundu. NTCP ile V30, MLD, MLDbiyo arasında pozitif korelasyon vardı (p 59,4 Gy alan hasta oranı, tümör BED3(Gy), BED10(Gy) daha fazla bulunurken (p= 0,02, p= 0,02, p= 0,02), >63 Gy alanlarda fark bulunamadı (p=0,3). Ellibeş Gy alan özafagus volümü RP olmayanlarda daha az bulundu (p=0,03). Medyan-2 yıl genel sağkalım (GSK) 27 ay, %51, medyan-2 yıl hastalıksız sağkalım (HSK); 18 ay, %42 bulundu. PET/BT ile 3. ay yanıt GSK için anlamlı idi (p= 0,009). Radyasyon pnömonisi ile GSK farkı bulunmadı (p= 0,3). Univaryat analizde; MLD yanında kalp V40 ?%80 GSK için (p= 0,03), kalp V40 ≤%80 ve kalp mean ≤2578 cGy HSK için (p= 0,005, p= 0,03) olumlu faktörler olarak bulundu. Multivaryat analizde; GSK için 6. ay yanıt (p= 0,001), fx dozu 1,8 Gy (p= 0,002), MLD 59,4 Gy (p= 0,01), tümör BED3(Gy) ≤100,8 Gy (p= 0,01) anlamlı bulundu. Çalışmamızda RP risk tahmini için MLD ile NTCP arasında doğrusal bir korelasyon olduğu gözlendi. Hastaya uygun RT tekniğini seçerken düşük doz alan büyük volüm dozları (V5-V10) ve yüksek doz alan küçük volüm dozlarına (V40-V50) dikkat etmemiz gerektiği ortaya konmuştur. MLD?nin 20 Gy altında tutulabildiği doz aralığı 59.4-63 Gy arasında olup terapötik aralığın adaptif RT teknikleri ile artırılabileceği düşünülmektedir.The patients with non-small cell lung cancer treated by definitive three-dimensional conformal radiotherapy (3DCRT) ± concurrent chemotherapy (CT) from 2009 to 2012 and those who survive for at least 6 months were analyzed. Total dose was converted to biological effective dose equivalent (BED) and normal tissue complication probability (NTCP) was calculated. Statistical analysis was performed with SPSS v.20 at 20 February 2013. The median age was 59 (range: 36-81) and a median of 63 Gy (range: 54-70 Gy) was delivered with conformal RT using customized blocks (n: 37), 3DCRT (n: 11) and intensity-modulated RT (IMRT) (n: 20). Neoadjuvant, concurrent, adjuvant CT were given to 29, 49, 41 patients, respectively. Acute grade (G) 1-3 esophagitis, acute G1-2 radiation pneumonitis (RP) and radiation fibrosis was developed with rates of 48%, 13%, and 18%, respectively. It was not demonstrated a significant relationship between RP and treatment type, RT dose, tumor BED, dosimetric factors and CT (p >0,05). There was a good correlation between physical and biological mean lung dose (MLD) (0,93). The median MLD, MLDbio, V30 and NTCP were found 17 Gy, 16,7 Gy, 20,5% and 0,142. There was a positive correlation between NTCP and V30, MLD, MLDbio (p 59.4 Gy, tumor BED3(Gy), BED10(Gy) (p= 0,02, p= 0,02, p= 0,02) in patients with MLD 63 Gy (p= 0,3). Volume of the esophagus received 55 Gy was lower in those without RP (p= 0,03). Median-2-year overall survival (OS) were found 27 months, 51% and median-2-year disease-free survival (DFS) were found 18 months, 42%. Response with PET/CT at 3 months was statistically significant for OS (p= 0,009). There was no difference in OS with RP (p= 0,3). On univariate analysis; besides MLD, heartV40 ≤80% for OS (p= 0,03) and heart V40 ≤80%, heart mean ≤2578 cGy for DFS (p= 0.005, p= 0.03) were found favorable factors. On multivariate analysis; response at 6 months (p= 0,001), fx dose 1.8 Gy (p= 0,002), MLD 59.4 Gy (p= 0,01), tumor BED3(Gy) ≤100.8 Gy (p= 0,01) were significant for DFS. In our study, a linear correlation was observed between MLD and NTCP in terms of risk prediction. It is showed that when choosing the individualized RT technique for patients should pay attention to the low doses to large volumes (V5-V10) and high doses to small volumes (V40-50). MLD can be kept below 20 Gy dose range of 59.4-63 Gy and therapeutic range is thought to be increased with adaptive RT techniques