Inclusion Criteria:

1. Patients must have histologically or cytologically confirmed adenocarcinoma or carcinoma of the pancreas that is metastatic and not amenable to resection with curative intent.
2. Patients must have measurable disease defined by Response Evaluation Criteria In Solid Tumors (RECIST) criteria. For the purpose of this study, primary mass in the pancreas is not considered as measurable disease.
3. Patients must have received one (1), and only one, prior systemic regimen for metastatic disease. Patients who have received prior cisplatin or oxaliplatin are eligible. A systemic regimen administered for unresectable locally advanced disease that subsequently progressed to metastatic will be counted as 1 prior regimen. Chemotherapy administered as adjuvant therapy or as a radiation sensitizer is not counted as a prior regimen.
4. Prior radiation is permitted; however, at least three (3) weeks must have elapsed since the completion of prior radiation therapy and patients must have recovered from all associated toxicities to National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) Version 3.0 </= Grade 1 at the time of registration. Measurable disease must be outside the previous radiation field or a new lesion inside the port must be present.
5. At least two weeks must have elapsed since any major surgery and patients must have recovered from all associated toxicities to </= CTCAE Grade 1 at the time of registration
6. At least 4 weeks must have elapsed since previous chemotherapy except for regimens that are administered on a daily, weekly, or every other week schedule, in which case at least 2 weeks must have elapsed since previous chemotherapy. Patients must have recovered from all associated toxicities to CTCAE </= Grade 1 at the time of registration
7. Age >/= 18 years. Because no dosing or adverse event data are currently available on the use of bortezomib in combination with carboplatin in patients <18 years of age, children are excluded from this study but will be eligible for future pediatric phase 2 combination trials.
8. Eastern Cooperative Oncology Group (ECOG) performance status </=1 (Karnofsky >/= 70%).
9. Patients must have adequate organ and marrow function as defined below: absolute neutrophil count >/= 1,500/mcL; platelets >/= 100,000/mcL; hemoglobin >/= 9 g/dl; total bilirubin </= 1.5 * institutional upper limit of normal; aspartate aminotransferase (AST or SGOT) and alanine aminotransferase (ALT or SGPT) </= 2.5 * institutional upper limit of normal or </= 5 * institutional upper limit of normal if patient has liver metastasis; creatinine </= 1.5 mg/dL OR creatinine clearance >/= 60 mL/min/1.73 m^2 for patients with creatinine levels above institutional normal.
10. Other prior malignancy is allowed as long as the patient does not require active treatment for their second malignancy and there is no radiographic evidence of second malignancy. Patients who are receiving hormonal therapy for breast or prostate cancer as adjuvant treatment are eligible.
11. The effects of bortezomib on the developing human fetus at the recommended therapeutic dose are unknown. For this reason and because carboplatin, the other therapeutic agent used in this trial, is known to be teratogenic, women of child-bearing potential and men of reproductive potential must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) 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.
12. Ability to understand and the willingness to sign a written informed consent document. Written informed consent must be obtained prior to any evaluations being performed solely for the purposes of screening for eligibility for this study.

Exclusion Criteria:

1. Patients who have only locally advanced disease (not metastatic) are excluded.
2. Patients who have received prior treatment with carboplatin, bortezomib, or another proteasome inhibitor are excluded.
3. 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. However, brain imaging studies are not required to assess eligibility if the patient has no neurological signs or symptoms.
4. Patients with current neurotoxicity, defined as greater than CTCAE Grade 1 neurotoxicity.
5. Patients must not be planning to receive any other concomitant anticancer treatment including chemotherapy, radiation therapy, biologic agents, or any other investigational drugs.
6. Patients must not have significant history of cardiac disease, i.e., unstable angina, congestive heart failure with New York Heart Association class 3 or 4, and myocardial infarction within the last 6 months.
7. Pregnant women are excluded from this study because bortezomib is a proteasome inhibitor agent with the potential for teratogenic or abortifacient effects. Carboplatin has been shown to be embryotoxic and teratogenic in rats. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with bortezomib and carboplatin, breastfeeding should be discontinued if the mother is treated with these drugs.
8. HIV-positive patients on combination antiretroviral therapy are ineligible because of the potential for pharmacokinetic interactions with bortezomib and carboplatin. In addition, these patients are at increased risk of lethal infections when treated with marrow-suppressive therapy. Appropriate studies will be undertaken in patients receiving combination antiretroviral therapy when indicated.