Nghiên cứu đặc điểm hình ảnh và giá trị CHT chẩn đoán phân độ giai đoạn T của ung thư bàng quang

Researching imaging characteristics and assessing values of MRI in the diagnosis of bladder cancer at T-stage

SUMMARY

Purpose: Describing imaging characteristics and assessing values of MRI in the diagnosis of bladder cancer at T-stage.

Subjects and methods: 43 patients with bladder tumors were selected to be in adescriptive study (38 of whom had tumors from tumor histopathology and 5 patients had histology from other organs or benign paraganglioma bladder tumor), in which they got diagnosed, operated (transurethral resection or radical cystectomy) and had pathology results from May 2017 to June 2018 at K hospital in Tan Trieu. All MRI films were evaluated preoperatively and compared with histopathology postoperativelydistinguishing superficial tumors (T1 or lower) and invasive tumors (T2 or higher).

Results: Among 38 patients being studied, the mean age is 56 ± 13.24 andthe gender ratio is M/F ≈ 7/1. Out of 61 tumors, the most common tumor location is bilateral bladder 30.7%, mostly one tumor (26/38). Featured images: mean size 23.47 ± 14.09 mm, max size 68mm, min size 7 mm; most frequently found polype-shaped tumor 25/38 patients (65.8%). According to the assessment of MRI results with T2W, DCE and DWI distinguishing T staging, tumors in T1 or lower 30/38 patients (78.9%) and T2 or higher 8/38 patients (21,1%, in which 4 patients in T2, one in T3 and 3 in T4). There is no correlation between the number of tumors and T staging (p>0.05). There is a strong correlation between the shape of tumors and T staging (p<0.001). When combining T2W with DCE, the sensitivity, specificity and overall accuracy of two observers for differentiating Tis to T1 tumor from T2 to T4 tumors were 79.3 %, 100% and 84.2% respectively. When using all three image types together (T2W, DCE and DWI) to assess T staging, the sensitivity rose up to 96.5%, specificity 66.7%, overall accuracy 89.5% and PPV 90.3%. The Cohen’s Kappa score of 0.685 had a good correlation between MRI results and histopathology in distinguishing T-staging of bladder cancer (p<0.001). In addition, a total 36 patients had urothelial carcinoma, ADC values of 29/36 patients at T1 or lower were 1.138 ×10–3mm2/s and 7/36 patients at T2 or higher were 0.79 × 10–3mm2/s, and this difference of ADC was significant between Grade 1 and Grade 3. The total of 29/38 patients (76.3%) underwent TUR and deep muscle biopsy was performed at the base tumor, 9/38 patients underwent radical cysectomy or chemotherapy before surgery.

Key words: Bladder Cancer, MRI of Bladder cancer.