Subphrenic Lymph Node Metastasis Predicts Poorer Prognosis for Nasopharyngeal Carcinoma Patients With Metachronous Metastasis.

AIM: We retrospectively analyzed the distribution of distant lymph node metastasis and its impact on prognosis in patients with metastatic NPC after treatment. METHODS: From 2010 to 2016, 219 NPC patients out of 1,601 (182 from the Affiliated Cancer Hospital and Institute of Guangzhou Medical University, and 37 from the Affiliated Dongguan Hospital, Southern Medical University) developed distant metastasis after primary radiation therapy. Metastatic lesions were divided into groups according to location: bones above the diaphragm (supraphrenic bone, SUP-B); bones below the diaphragm (subphrenic bone, SUB-B); distant lymph nodes above the diaphragm (supraphrenic distant lymph nodes, SUP-DLN); distant lymph nodes below the diaphragm (subphrenic distant lymph nodes, SUB-DLN), liver, lung, and other lesions beyond bone/lung/distant lymph node above the diaphragm (supraphrenic other lesions, SUP-OL); other lesions beyond bone/liver/distant lymph node below the diaphragm (subphrenic other lesions, SUB-OL); the subtotal above the diaphragm (supraphrenic total lesions, SUP-TL); and the subtotal below the diaphragm (subphrenic total lesions, SUB-TL). Kaplan-Meier methods were used to estimate the probability of patients' overall survival (OS). Univariate and multivariate analyses were applied using the Cox proportional hazard model to explore prediction factors of OS. RESULTS: The most frequent metastatic locations were bone (45.2%), lung (40.6%), liver (32.0%), and distant lymph nodes (20.1%). The total number of distant lymph node metastasis was 44, of which 22 (10.0%) were above the diaphragm, 18 (8.2%) were below the diaphragm, and 4 (1.8%) were both above and below the diaphragm. Age (HR: 1.02, 95% CI: 1.00, 1.03, p = 0.012), N stage (HR: 1.26, 95% CI: 1.04, 1.54, p = 0.019), number of metastatic locations (HR: 1.39, 95% CI: 1.12, 1.73, p = 0.003), bone (HR: 1.65, 95% CI: 1.20, 2.25, p = 0.002), SUB-B (HR: 1.51, 95% CI: 1.07, 2.12, p = 0.019), SUB-DLN (HR: 1.72, 95% CI: 1.03, 2.86, p = 0.038), and SUB-O L(HR: 4.46, 95% CI: 1.39, 14.3, p = 0.012) were associated with OS. Multivariate analyses revealed that a higher N stage (HR: 1.23, 95% CI: 1.00, 1.50, p = 0.048), SUB-DLN (HR: 1.72, 95% CI: 1.02, 2.90, p = 0.043), and SUB-OL (HR: 3.72, 95% CI: 1.14, 12.16, p = 0.029) were associated with worse OS. CONCLUSION: Subphrenic lymph node metastasis predicts poorer prognosis for NPC patients with metachronous metastasis; however, this needs validation by large prospective studies.

[Role of 18F-FDG PET/CT in diagnosis and staging of nasopharyngeal carcinoma].

BACKGROUND & OBJECTIVE: Because (18)F-FDG PET/CT can display cancer lesion morphology, size and the relatinship of the cancer lesion to adjacent tissues, it is used in the diagnosis and classification of nasopharyngeal carcinoma (NPC). This study was to explore the application value of (18)F-FDG PET/CT in TNM staging by comparing the performance of MRI and PET/CT together with pathological results for some small lymph nodes. METHODS: Sixty-eight pathologically proven NPC patients were selected from Sep.2005 to Mar. 2007 in Sun Yat-sen University Cancer Center. All cases underwent both MRI and (18)F-FDG PET/CT examinations. PET/CT two-dimensional (2D) data were collected. Automatic dose tracking scanning and contrast-enhanced CT scanning were performed. (18)F-FDG was intravenously administrated at a dose of 3.7-5.5 MBq/kg. MRI T1W, T2W and T1W Gd-DTPA enhanced images were obtained. Neck lymph nodes of 10 NPC patients were pathologically examined. RESULTS: Nasopharyneal lesions of all 68 cases were all clearly displayed by both PET/CT and MRI. Among 138 small lymph nodes smaller than 1cm in diameter, which were positively detected by PET/CT, only 28.0% were suggested questionable by MRI scanning. Fourteen out of sixteen (87.5%) positive lymph nodes detected by PET/CT from 10 patients were pathologically confirmed. Both PET/CT and MRI revealed enlarged lymph nodes of the neck. Some lymph nodes whose proliferation was inhibited during radiotherapy suggested by PET/CT were displayed intensified images by contrast-enhanced PET/CT and MRI. Metastases to lung, bone and liver in eight stage IVb patients were clearly displayed by PET/CT, but not by MRI. The stage of 24 patients was adjusted after PET/CT scanning. CONCLUSIONS: (18)F-FDG PET/CT with automatic dose tracking scanning protocol and contrast-enhanced scanning can provide more comprehensive information than MRI in diagnosing and staging NPC.

[Primary investigation of dose-effect relationship of 153Sm-EDTMP in treating multiple bone metastases].

BACKGROUND & OBJECTIVE: Dose calculation of radionuclide internal irradiation is a hot topic and difficulty of nuclear medical researches. This study was to calculate the focus absorption dose of 153Sm-EDTMP with the Monte Carlo EGS4 method for treatment of bone metastases from nasopharyngeal carcinoma or breast cancer, and investigate the relationship between the focus absorption dose and painkilling effect of 153Sm-EDTMP. METHODS: Four patients with multiple bone metastases from nasopharyngeal or breast carcinoma and suffered from grade IV bone pain were treated with radionuclide internal irradiation of 153Sm-EDTMP. The absorption dose and dose distribution of bone metastases and other targeted organs were calculated with MC EGS4 program based on the time-order SPECT/CT scanning and the measurement of the radioactivity in the urine accumulation. The release of bone pain and the improvement of life quality were observed. RESULTS: Bone pain of the patients was significantly alleviated to grade II for 3-4 weeks after internal 153Sm-EDTMP irradiation. The 3-dimensional absorption dose distribution image of bone metastases and targeted organs showed that the dose distribution in bone metastases was not asymmetrical. After injection of 0.65x37 MBq/kg 153Sm-EDTMP, the highest absorption dose in bone lesions was about 4.9-5.9 Gy, and the dose in the lesion margin was about 2.0 Gy. Use the highest dose as reference dose point, the relative absorption dose values of bone marrow, bone cortex, and soft tissue near lesions were 0.48-1.1 Gy, 0.51-0.85 Gy, and 0.01-0.14 Gy, respectively. CONCLUSIONS: The absorption dose of bone metastases is significantly lower than treatment dose of 30 Gy after single irradiation of 153Sm-EDTMP. The painkilling effect is limited and in accordance with clinical observation.

[Application of molecular imaging to chemotherapy].

Molecular imaging is a new subject of exploring the biological metabolism process of the cells or organs in living organisms with some non-invasive technologies, such as PETE-CT, MR, and optical imaging instruments, using specific molecular probes to investigate the pathologic and physiologic metabolisms of the patients at molecular and gene levels. With the development of this technology, molecular imaging plays a more and more important role in guiding cancer chemotherapy, choosing sensitive medicines, planning treatment scheme, evaluating chemotherapy effect, and so on.