Value of PET/CT in diagnosis of lung cancer – Bui Anh Thang

Journal of military pharmaco-medicine n o 8-2018 170 VALUE OF PET/CT IN DIAGNOSIS OF LUNG CANCER Bui Anh Thang1; Pham Ngoc Hoa1; Do Quyet2 SUMMARY Objectives: To remark on SUV of PET/CT in small-cell and non-small cell lung cancer and determine the value of PET/CT in the diagnosis of lung cancer. Subjects and methods: 58 patients diagnosed with lung cancer on PET/CT (24 patients with small cell and 34 patients with non-small cell in Oncology and Nuclear Medicine Center of Bachmai Hospital, from August 2010 to October 2015. Patients were performed with PET/CT to diagnose with lung cancer (size, metastasis) and compared with histopathological results. Results: 24 patients were diagnosed with small cell lung cancer, 33 patients were diagnosed with non-small cell lung cancer and 1 patient with benign lesion. The average of SUV was 5.91 ± 2.12. The average SUV was higher significantly in group of non-small cell than small cell lung cancer (6.58 ± 2.35 vs. 5.01 ± 1.35; p < 0.01). PET/CT diagnosis of lung cancer had the accuracy of 98.3%. Conclusion: PET/CT diagnosis of lung cancer has a very high accuracy. * Keywords: Lung cancer; Non-small cell lung cancer; PET/CT; Value. INTRODUCTION Lung cancer is the most common cause of cancer death in Europe in 2006 (about 334,800 deaths) and is the second frequent type of cancer after prostate cancer in men. The morbidity and mortality rate in 2006 was 75.3 and 64.8 per 100,000 people per year, respectively [2]. In Vietnam, according to the cancer epidemiology record in 2004, lung cancer was the leading one among men with the incidence in Hanoi of 39.8/100,000 [1]. Late detection of lung cancer can result in poor prognosis, high mortality and death in a short time. Early diagnosis and evaluation of lung cancer is essential and urgent. So we made this study with a view to: Examining SUV value of small and non-small cell lung cancer and determining the value of PET/CT in the diagnosis of lung cancer. SUBJECTS AND METHODS 1. Subjects. 58 patients diagnosed with lung cancer on PET/CT in Nuclear Medicine and Cancer Center, Bachmai Hospital, with histopathological examination. Study time: from August 2010 to October 2015. 2. Methods. - Design study description: + SUV value of small and non-small cell lung cancer. 1. Pham Ngoc Thach Medical University 2. Vietnam Military Medical University Corresponding author: Bui Anh Thang (anhthangcdha@gmail.com) Date received: 17/08/2018 Date accepted: 26/09/2018 Journal of military pharmaco-medicine n o 8-2018 171 + Determine the value of PET/CT for definite diagnosis and metastatic detection in lung cancer. - The study variables included age, gender, PET/CT variables (including SUV, tumor size, metastatic location, diagnosis of lung cancer), pathology (lung cancer) small cells, non-small cell lung cancer, inflammatory lesions. - Process of survey PET/CT: + Video recorder PET/CT: PET/CT Biograph True Point - Siemens (Germany). + Prepare the patient: Patients abstain from food at least 4 hours before PET/CT. Patients were examined, exploited a history of illness, records for each patient, measurement of weight, height, pulse, blood pressure, temperature. Check the blood glucose before injection 18F-FDG (blood sugar must be less than 8.0 nmoL/L). - Place a fixed intravenous line. After 18F-FDG injection, the patient stayed at the monitoring room, limiting movement and speech before shooting. Patients should urinate before shooting. 18F-FDG: 18F-FDG (2-fluoro-2-deoxy-D- glucose solution). Dosage: 0.15 - 0.20 mCi/kg body weight (7 - 12 mCi) intravenously. PET/CT: Performed after 18F- FDG 45 - 60 min. Capture whole body from skull base to 1/3 on femur. Capture additional areas. + Image processing and results recognition: The results were analyzed after PET imaging, CT imaging, PET/CT integration and absorption and distribution of 18F-FDG. Qualitative indices such as size, volume of injury, density, SUV were also measured for each of the losses to combine the results of the final evaluation. SUV = [mCi/mL (calibrated decomposition) of tissue organization]/[injection dose (mCi)/gram weight). The SUV value of the lesion found was compared to the median blood vessel volume in the mediastinum (average SUV = 2.5). With SUV values of 2 - 2.5, suspicion of benign and malignant lesions. SUV values > the activity of blood vessels in the mediastinum (2.5) can identify malignant lesions. - Comparisons of PET/CT results with histopathological findings: PET/CT (+): PET/CT images diagnosed with lung cancer. PET/CT (-): The PET/CT image is not diagnosed with lung cancer. Pathological anatomy results (+): surgery for lung cancer. Pathological anatomy results (-): anxiety is a benign lesion. - Data processing: According to the software SPSS 22.0. RESULTS 1. Age and gender. Table 1: Age and gender. Features Small cell lung cancer (n = 24) Non-small cell lung cancer (n = 33) Total (n = 57) Minimum age 44 34 34 Maximum age 81 74 81 Mean age 61.1 ± 8.6 59.7 ± 8.2 60.3 ± 8.3 Sex (male) 22 (91.7%) 24 (72.7%) 46 (80.7%) Mean age of lung cancer patients was 60.3 ± 8.3; no difference between small and non-small cell groups, minimum age 34, the oldest 81. Mostly were male patients (80.7%). Journal of military pharmaco-medicine n o 8-2018 172 2. Histologic diagnosis. Table 2: Classification of lung cancer based on histopathological findings. Classification Patients (n) Rate (%) Small cell lung cancer 24 42.1 Squamous cell carcinoma 6 10.5 Non-small cell lung cancer Adenocarcinoma 27 47.4 Total 57 100 Of 57 lung cancer patients, 24 cases suffered from small cell lung cancer, 33 patients had non-small cell lung cancer (of which squamous cell carcinoma and adenocarcinoma accounted for 10.5%; 47.4%, respectively). 3. Metastatic rate. Table 3: Classification Patients Patients with metastasis (n) Metastatic rate (%) Small cell lung cancer 24 21 87.5 Non-small cell lung cancer 33 28 84.8 Total 57 49 86.0 The prevalence of lung cancer was 86.0%; of which 87.5% for small cell spam and 84.8% for non-cell cancers. 4. The SUV of the primary tumor. Table 4: SUV Small cell lung cancer (n = 24) Non-small cell lung cancer (n = 33) Total (n = 57) Minimum 2.82 3.07 2.82 Maximum 8.38 13.39 13.39 Mean 5.01 ± 1.35 6.58 ± 2.35 (**) 5.91 ± 2.12 (**: p < 0.01) The mean SUV compatible with the SUV was 5.91 ± 2.12, with SUVs in the non-small cell lung group significantly higher than in the small cell population (6.58 ± 2.35 vs. 5.01 ± 1.35, p < 0.01). Journal of military pharmaco-medicine n o 8-2018 173 5. Value of PET/CT in the diagnosis of lung cancer. Table 5: Comparing the PET/CT findings with the histopathology result. Histopathology (+) Histopathology (-) Total PET/CT (+) 57 1 58 PET/CT (-) 0 0 0 Total 57 1 58 The rate of PET/CT diagnosed with lung cancer was 57/58, accounting for 98.3%. DISCUSSION In the world, lung cancer is the most common cause of cancer death among men and women [3]. Non-small cell lung cancer and small cell lung cancer (based on histopathological classification) account for about 85% and 15%, respectively [4]. Patients with small cell lung cancer are mostly males (80.7%), mean age 60. The results of our study are consistent with Park M.R et al’s findings: The average age of patients was 65.66 years and 85.5% were males [5]. In the 57 patients with lung cancer, there were 24 cases of small cell lung cancer, 33 non-small cell lung cancer (of which 10.5% were squamous cell carcinoma, adenocarcinoma carcinoma occupied 47.4%). According to our results, the metastatic rate in lung cancer was 86.0%. In particular, small cell lung cancer had a metastatic rate of 87.5% and 84.8% for non-small cell lung cancer. Thus, although the tumor was small in size, this type of cancer often precedes metastatic non-small cell lung cancer. SUV value for moderate lung cancer: 5.91 ± 2.12, in which SUV values in non- small cell groups were significantly greater than small cell groups (6.58 ± 2.35 vs. 5.01 ± 1.35; p < 0.01). PET/CT is very valuable in assessing lung cancer. In addition, PET/CT helps to diagnose and differentiate primary cancer and lung metastatic lesions: ∆SUV was significantly higher in patients with primary cancer than in lung metastases [6]. The SUV's value assortment helps to distinguish benign tumors and benign lesions in the lung, thereby providing a basis for the development of appropriate treatment regimens. PET/CT is a very good imaging technique, with a higher sensitivity, specificity and accuracy than CT and MRI alone in the diagnosis of lung cancer and assessment of lung cancer stage [2]. Our study showed that the rate of PET/CT diagnosed with lung cancer was 57/58, compared with 57/58 cases, accounting for a very high proportion (98.3%). Journal of military pharmaco-medicine n o 8-2018 174 Figure 1: Primary tumors (non-small cell lung cancer). Figure 2: Primary tumors (small cell lung cancer). Journal of military pharmaco-medicine n o 8-2018 175 Figure 3: Bone metastasis from small cell lung cancer. Figure 4: Lymph node in small cell lung cancer. Journal of military pharmaco-medicine n o 8-2018 176 Figure 5: Lymph node in non-small cell lung cancer. CONCLUSION SUV for moderate lung cancer was 5.91 ± 2.12, with SUVs in the non-small cell lung cancer group were significantly higher than in the small cell group (6.58 ± 2.35 and 5.01 ± 1.35). PET/CT diagnosed with lung cancer was an accuracy of 98.3% compared to the histopathologic result. REFERENCE 1. Nguyễn Bỏ Đức. Tỡnh hỡnh ung thư ở Việt Nam giai đoạn 2001 - 2004. Tạp chớ Y học Thực hành. 2006, tr.9-17. 2. Sứrensen M, Pijls-Johannesma M, Felip E; ESMO Guidelines Working Group. Small- cell lung cancer: ESMO clinical practice guidelines for diagnosis, treatment and follow- up. Ann Oncol. 2010, 21 Suppl 5, pp.120-125. 3. Jemal A, Siegel R, Xu J, Ward E. Cancer statistics. CA Cancer J Clin. 2010, 60, pp.277-300. 4. Brambilla E, Travis W.D, Colby T.V, Corrin B, Shimosato Y. 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