Prolonged survival in a nasopharyngeal carcinoma patient with multiple metastases: a case report and review of the literature

Subdivision of M category for nasopharyngeal carcinoma with synchronous metastasis: time to expand the M categorization system

INTRODUCTION

The current metastatic category (M) of nasopharyngeal carcinoma (NPC) is a "catch-all" classification, covering a heterogeneous group of tumors ranging from potentially curable to incurable. The aim of this study was to design an M categorization system that could be applied in planning the treatment of NPC with synchronous metastasis.

METHODS

A total of 505 NPC patients diagnosed with synchronous metastasis at Sun Yat-sen University Cancer Center between 2000 and 2009 were involved. The associations of clinical variables, metastatic features, and a proposed M categorization system with overall survival (OS) were determined by using Cox regression model.

RESULTS

Multivariate analysis showed that Union for International Cancer Control (UICC) N category (N1-3/N0), number of metastatic lesions (multiple/single), liver involvement (yes/no), radiotherapy to primary tumor (yes/no), and cycles of chemotherapy (>4/≤4) were independent prognostic factors for OS. We defined the following subcategories based on liver involvement and the number of metastatic lesions: M1a, single lesion confined to an isolated organ or location except the liver; M1b, single lesion in the liver and/or multiple lesions in any organs or locations except the liver; and M1c, multiple lesions in the liver. Of the 505 cases, 74 (14.7%) were classified as M1a, 296 (58.6%) as M1b, 134 (26.5%) as M1c, and 1 was not specified. The three M1 subcategories showed significant difference in OS [M1b vs. M1a, hazard ratio (HR) = 1.69, 95% confidence interval (CI) = 1.16-2.48, P = 0.007; M1c vs. M1a, HR = 2.64, 95% CI = 1.75-3.98, P < 0.001].

CONCLUSIONS

We developed an M categorization system based on the independent factors related to the prognosis of patients with metastatic NPC. This system may be helpful to further optimize individualized care for NPC patients.

Partial hepatectomy for liver metastases from nasopharyngeal carcinoma: a comparative study and review of the literature

BACKGROUND

The management of liver metastases from nasopharyngeal carcinoma (NPC) has not been extensively investigated. This study aimed to compare the long-term outcome of patients with liver metastases from NPC who were treated by a partial hepatectomy or transcatheter hepatic artery chemoembolization (TACE).

METHODS

Between January 1993 and December 2010, 830 patients were diagnosed with liver metastases from NPC and exhibited a complete response to the primary cancer of the nasopharynx and regional lymph nodes. Fifteen patients with intrahepatic metastasis underwent R0 partial hepatectomy. As a parallel control group, another 15 patients with a resectable liver metastasis who underwent TACE were selected. Prior to the resection and TACE that were performed on patients in these two groups, radical radiotherapy with or without adjuvant chemotherapy was administered. Clinicopathological data and treatment outcomes were compared retrospectively.

RESULTS

No significant differences were observed between the two groups in terms of the clinicopathological features, which include gender ratio, liver function, accompanying cirrhosis, rate of infection with the hepatitis B virus, tumor size, tumor number, pathological type and preoperative comorbidities. The 1-, 3- and 5-year overall survival rates from the time of hepatectomy were 85.7%, 64.2% and 40.2%, respectively, with a median survival of 45.2 months, whereas the 1-, 3- and 5-year overall survival rates were 53.3%, 26.6% and 20.0% for patients in the control group (P = 0.039), respectively, with a median survival of 14.1 months. The actuarial median progression-free survival (PFS) of the patients in the resection group was 21.2 months, and the 1-, 3- and 5-year PFS rates were 70%, 53% and 18%, respectively. In the control group, the 1-, 3- and 5-year PFS rates were 27%, 7% and 0.0% (P = 0.007), respectively, with a median survival of 4.2 months. Thus far, 5 patients have survived for more than 5 years, and the longest survival time is 168.1 months.

CONCLUSIONS

For patients with limited liver metastases from NPC, hepatectomy provides a survival advantage over TACE. Due to the limited treatment options for patients with liver metastasis from NPC, hepatectomy should be recommended as an optimal treatment. Moreover, perioperative chemotherapy may be associated with an improved prognosis.

Prognostic factors in nasopharyngeal carcinoma with synchronous liver metastasis: a retrospective study for the management of treatment

PURPOSE

To retrospectively analyze the prognosis of patients with nasopharyngeal carcinoma (NPC) initially presenting with liver metastasis, in order to identify independent prognostic factors to facilitate management of treatment.

METHODS

Eighty-five patients with untreated NPC and synchronous liver metastasis, initially diagnosed between January 2000 and December 2009, were selected for this retrospective study. Seventy-eight received systemic chemotherapy, 32 underwent subsequent radiotherapy of the primary tumor, and 18 received local therapy for metastatic lesions. Clinical features, laboratory parameters and treatment modalities were compared by univariate and multivariate analyses.

RESULTS

The median survival time was 19.0 months and the 3-year overall survival rate was 14.1%. The overall response and disease control rates were 70.4% and 86.4%, respectively. Significant predictors of short survival were KPS ≤ 70 (P = 0.03), serum lactate dehydrogenase levels >245 IU/l (P = 0.01) and poor response to chemotherapy (P < 0.01). In contrast, significantly longer survival rates were achieved by patients having at least six chemotherapy cycles compared to those receiving <6 cycles (3-year OS: 18.3% vs. 7.1%; P < 0.01), and patients receiving radiotherapy of the primary tumor following complete or partial response to chemotherapy (3-year OS: 30.8% vs. 3.8%, P < 0.01).

CONCLUSIONS

Five key independent factors were identified and sub-classified as potential prognostic indicators for NPC with liver metastases. Progressive treatments of systemic chemotherapy and radiotherapy at the primary tumor could prolong survival in the subset of patients having fewer negative prognosticators.

Subdividing the M1 stage of liver metastasis for nasopharyngeal carcinoma to better predict metastatic survival

In nasopharyngeal carcinoma (NPC), the M1 stage of the TNM classification does not differentiate between the site of metastasis or the number of metastatic lesions. However, NPC patients with lung or bone metastases survive longer than do those with liver metastasis (LM). We subdivided the M1 stage of LM to better predict survival in these patients. From the records of 305 NPC patients with LM treated at Sun Yat-sen University Cancer Center between January 2000 and December 2007, we determined the effects of clinical characteristics and the subclassifications of the M1 stage for LM characteristics [the number, size, timing (synchronous vs. metachronous), and distribution of metastases and metastases to other organs] on survival since the diagnosis of LM. Metastatic survival rates were 62% at 1 year, 31% at 2 years, and 21% at 3 years. Having 1-3 metastatic lesions, having lesions less than 5 cm in diameter, and having unilobular LM were better univariate predictors of metastatic survival. Better survival was independently predicted by having one to three (vs. more than three) metastatic lesions (hazards ratio=0.52; 95% CI=0.33-0.82) and unilobular (vs. bilobular) lesions (hazards ratio=0.35; 95% CI=0.22-0.57). The current report constitutes large samples of LM from NPC from our single institution with correlation between LM characteristics and metastatic survival. Patients with NPC and one to three liver metastases or unilobular metastases survive longer than their counterparts, and aggressive treatment should be considered.

Tumor growth inhibition of metastatic nasopharyngeal carcinoma cell lines by low dose of arsenic trioxide via alteration of cell cycle progression and induction of apoptosis

BACKGROUND

Although arsenic trioxide (ATO) has displayed anticancer activity against primary nasopharyngeal carcinoma (NPC), its efficacy in metastatic NPC deserved further investigation because the biological/therapeutic difference in cancer cells probably exists between primary and distant sites.

METHODS

Two human metastatic NPC cell lines (NPC-BM1 and NPC-BM2) were investigated. We measured cellular proliferation, cell cycle, and apoptotic extent of BM1 and BM2 cells treated with ATO in vitro. Furthermore, we evaluated the tumor growth after ATO treatment in vivo.

RESULTS

Low-dose ATO treatment is sufficient to induce an antiproliferative effect, alter the cell cycle, and increase apoptosis in BM1 and BM2 cells. BM1 tumor growth in a xenograft model with low-dose and short-schedule (1 mg/kg/day, intraperitoneal injection for 5 consecutive days) of ATO treatment significantly slowed in vivo.

CONCLUSION

ATO at low dose seems to be an encouraging schedule for palliative treatment of metastatic NPC.