Combination Chemotherapy in Treating Patients With Recurrent, Refractory, or Metastatic Solid Tumors or Lymphomas

DISEASE CHARACTERISTICS:

* Diagnosis of cancer that has failed standard therapy or for which no such therapy exists, including, but not limited to:

  * Unresectable primary or recurrent solid tumors (e.g., colon, pancreatic, lung, esophageal, or cholangiocarcinoma)
  * Metastatic disease
  * Lymphoma with no prior high-dose chemotherapy requiring autologous or allogeneic stem cell rescue
* No leukemias
* No CNS metastases or primary CNS malignancies
* No failure on prior gemcitabine therapy

PATIENT CHARACTERISTICS:

Age:

* 18 and over

Performance status:

* ECOG 0-2

Life expectancy:

* Not specified

Hematopoietic:

* Absolute granulocyte count at least 2,000/mm\^3
* Platelet count at least 100,000/mm\^3

Hepatic:

* Bilirubin no greater than 2.0 mg/dL
* Transaminases less than 6 times upper limit of normal

Renal:

* Creatinine no greater than 2.0 mg/dL

Other:

* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* No other serious concurrent medical illness that would preclude study
* No active infections requiring IV antibiotics
* HIV negative

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* See Disease Characteristics
* More than 4 weeks since prior immunotherapy and recovered

Chemotherapy:

* See Disease Characteristics
* More than 4 weeks since prior chemotherapy (at least 6 weeks for mitomycin or nitrosoureas) and recovered
* At least 3 months since prior suramin
* At least 5 weeks since prior eniluracil (8 weeks prior to start of fluorouracil) and recovered

Endocrine therapy:

* No steroid therapy if utilized for chronic lymphoma therapy
* At least 4 weeks since prior steroidal therapy as disease treatment

Radiotherapy:

* At least 2 weeks since prior radiotherapy to no more than 20% of bone marrow
* At least 4 weeks since prior radiotherapy to 21% or more of bone marrow
* Recovered from prior radiotherapy

Surgery:

* Recovered from prior surgery

Other:

* No concurrent cimetidine