Bortezomib, Paclitaxel, and Carboplatin in Treating Patients With Unresectable, Metastatic Cancer of the Esophagus or Gastroesophageal Junction

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed adenocarcinoma of 1 of the following sites: Esophagus Gastroesophageal junction Gastric cardia No greater than 2 cm from the gastroesophageal junction into the stomach Unresectable, metastatic disease Not a candidate for potentially curative therapy AND no other more reasonable potentially curative conventional therapy exists At least 1 measurable lesion ≥ 2.0 cm by conventional techniques OR ≥ 1.0 cm by spiral CT scan No known CNS metastases PATIENT CHARACTERISTICS: Age 18 and over Performance status ECOG 0-2 Life expectancy At least 12 weeks Hematopoietic Absolute neutrophil count ≥ 1,500/mm^3 Platelet count ≥ 100,000/mm^3 Hepatic Bilirubin normal AST ≤ 3 times upper limit of normal (ULN) Alkaline phosphatase ≤ 2 times ULN Renal Creatinine ≤ 1.5 times ULN Other Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for up to 6 months after completion of study treatment No peripheral neuropathy ≥ grade 2 No uncontrolled infection No chronic debilitating disease No prior allergic reaction to carboplatin or paclitaxel No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer PRIOR CONCURRENT THERAPY: Biologic therapy No prior immunotherapy for recurrent or metastatic disease No prior biologic therapy for recurrent or metastatic disease No concurrent prophylactic colony-stimulating factors (filgrastim [G-CSF] or sargramostim [GM-CSF]) Chemotherapy No prior chemotherapy for recurrent or metastatic disease Prior chemotherapy in the neoadjuvant or adjuvant setting (after complete resection of the original tumor) allowed Prior combination chemotherapy and radiotherapy allowed provided patient achieved a complete response AND the last dose of combination therapy was administered ≥ 6 months ago Endocrine therapy Not specified Radiotherapy See Chemotherapy No prior radiotherapy for recurrent or metastatic disease Prior radiotherapy in the neoadjuvant or adjuvant setting (after complete resection of the original tumor) allowed No prior radiotherapy to > 25% of bone marrow for locally advanced disease More than 4 weeks since prior radiotherapy Surgery More than 4 weeks since prior open abdominal exploration (e.g., laparotomy) More than 2 weeks since prior minimally invasive procedures (e.g., laparoscopy)