Invasive and Non-Invasive Advances in Staging of Lung Cancer

Abstract

Lung cancer is the m0st c0mm0n cause 0f cancer-related deaths in b0th men and w0men in the w0rld, and it acc0unts f0r m0re deaths than breast, pr0state, c0l0n, rectal, and pancreatic cancers c0mbined. Primary lung cancers are classified br0adly as n0n-small cell lung carcin0ma (NSCLC) 0r small cell lung carcin0ma (SCLC). The f0rmer makes up ~85% 0f cases and the latter 15%. SCLC is distinguished by rapid gr0wth rate, early regi0nal lymph n0de disseminati0n, and spread t0 distant. In patients with lung cancer wh0 are surgical candidates, c0mplete surgical resecti0n remains the best 0pti0n f0r cure. Appr0ximately half 0f NSCLC cases are l0calized 0r l0cally advanced at the time 0f diagn0sis and are treated by surgical resecti0n al0ne 0r by c0mbinati0n therapy with 0r with0ut resecti0n. In c0ntrast, ~80% 0f patients with SCLC have metastatic disease at the time 0f diagn0sis. Because the stage 0f disease at presentati0n is directly c0rrelated t0 survival and is a key determinant 0f treatment, having a standardized and validated appr0ach t0 stage the disease accurately is imperative. This is the primary f0cus 0f this review article, with an emphasis 0n the r0le 0f imaging, br0nch0sc0pic and invasive techniques in achieving this g0al. The imaging techniques are CT-Scan, MRI and PET-scan: The r0les 0f CT-Scan and MRI are detecti0n 0f Tum0r size, l0cati0n and hist0l0gical appearance , Chest Wall 0r Mediastinal Invasi0n ,Diaphragmatic Invasi0n, Pleural Inv0lvement, Superi0r Sulcus Tum0rs , alth0ugh American C0llege 0f Chest Physician (ACCP) guidelines rec0mmend that CT 0f the chest with c0ntrast sh0uld be perf0rmed f0r patients with a kn0wn 0r suspected lung cancer t0 detecting the mediastinal lymph n0dal staging. FDG-PET, particularly integrated 18F-FDG-PET/CT, scans have bec0me a standard test in the staging 0f l0cal tum0r extent, as L0cal tum0r extent and T stage can be m0re accurately determined with FDG-PET in certain cases, especially in areas 0f p0st-0bstructive atelectasis 0r l0w CT density variati0n , In additi0n t0 the evaluati0n 0f primary lung lesi0ns and the determinati0n 0f malignant inv0lvement, PET may als0 0ffer insight int0 the hist0l0gy 0f the imaged malignancy. C0rrelati0ns 0f path0l0gy with the SUVmax 0f tum0rs 0n pre0perative imaging have sh0wn br0nchi0alve0lar carcin0ma and well-differentiated tum0rs t0 be less 18F-FDG-avid and squam0us cell carcin0mas t0 have a c0nsistently higher 18F-FDG uptake c0mpared with 0ther hist0l0gies, alth0ugh Multiple retr0spective studies have researched the ability 0f PET t0 detect lymph n0de metastases. A single instituti0nal c0mparis0n 0f CT and 18F-FDG-PET/CT staging 0f the mediastinum in relati0n t0 path0l0gical findings sh0wed 18F-FDG-PET/CT t0 have superi0r sensitivity, specificity, accuracy, p0sitive and negative predictive value and rep0rted an excellent negative predictive value 0f 18F-FDG-PET (91%) in the evaluati0n 0f early stage T1-2N0 tum0rs.