Combination of Gemcitabine and Carboplatin in Metastatic or Recurrent Nasopharyngeal Carcinoma

Inclusion Criteria:

1. Written informed consent obtained from patient or parents/guardian.
2. Subject age greater than or equal to 18 years
3. Histologically proven recurrent or metastatic undifferentiated or squamous nasopharyngeal carcinoma, not amenable to local therapy.
4. Measurable disease in distant sites and/or loco-regional sites defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded as \>=10mm with CT scan or MRI. Tumour lesions that are situated in a previously irradiated field are measurable only if the tissue planes are preserved on CT or MRI).
5. Prior concurrent chemotherapy and radiation therapy is permitted.
6. Primary chemo-radiotherapy must be completed at least 6 months prior to study entry.
7. Life expectancy over 3 months.
8. ECOG performance status less than or equal to 2.
9. Patients must have normal organ and marrow function as follows:

   * White blood cell count : \>= 3.0 x 10\^9/L
   * Absolute neutrophil count : \>= 1.5 x 10\^9/L
   * Platelets : \>= 100 x 10\^9/L
   * Total bilirubin : within normal limits
   * AST/ALT/ALP : \<= 2.5 x upper limit of normal
   * Creatinine clearance or estimated GFR : \>=50 mls/min.

Exclusion Criteria:

Patients with any of the following are not eligible for enrollment into the study:

1. Pregnant women are excluded from this study because gemcitabine has potential for teratogenic or abortifacient effects. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with gemcitabine, breastfeeding should be discontinued if the mother is treated with gemcitabine. These potential risks may also apply to other agents used in this study.
2. Women of child-bearing potential and men without an adequate contraception prior to study entry and for the duration of study participation. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately.
3. Prior use of gemcitabine
4. History of allergic reactions attributed to compounds of similar chemical or biologic composition to gemcitabine or carboplatin.
5. Prior lines of chemotherapy for metastatic NPC
6. Prior radiotherapy to the indicator lesion(s) to be measured in the study.
7. Patients receiving any other investigational agents
8. Patients with known brain metastases should be excluded from this clinical trial because of their poor prognosis and because they often develop progressive neurologic dysfunction that would confound the evaluation of neurologic and other adverse events.
9. Patients with bone-only metastases.
10. Clinically significant cardiac disease (e.g. congestive cardiac failure, symptomatic coronary artery disease and cardiac arrhythmias not well controlled with medication) or myocardial infarction within the last 12 months.
11. Severe sensorineural hearing loss affecting normal daily activities or requiring the use of hearing aids.
12. Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection or psychiatric illness/social situations that would limit compliance with study requirements.
13. Patients with immune deficiency. They are at increased risk of lethal infections when treated with marrow-suppressive therapy.
14. HIV-positive patients receiving combination antiretroviral therapy. There is a possible pharmacokinetic interaction between antiretroviral and gemcitabine or other agents administered during the study. Appropriate studies will be undertaken in patients receiving combination antiretroviral therapy when indicated.