Phase I/II Trial of Rhenium 188-P2045 in Small Cell Lung Cancer and Other Advanced Neuroendocrine Carcinomas

Inclusion Criteria:

* Age \>/=18 years.
* Advanced, metastatic or locally recurrent, incurable neuroendocrine tumors (small cell lung cancer, extrapulmonary small cell lung cancer, large cell neuroendocrine lung carcinoma pulmonary carcinoid, GI carcinoid tumor
* Symptomatic CNS metastases: must have received therapy (surgery, XRT, gamma knife)
* Asymptomatic CNS metastatic disease: discuss with Study Chair.
* Histologically-or cytologically documented disease.
* Considered incurable by any combination of therapy including surgery, radiation, chemotherapy.
* ECOG Performance status 0-2
* Renal function: creatinine clearance \> 40 mg/mlxmin (Cockroft-Gault)
* Adequate organ and marrow function by:
* Absolute neutrophil count (ANC) \>/=1,500/mcL.
* Platelets \>/= 100,000/mcL.
* Total bilirubin within normal institutional limits (WNL)
* AST (SGOT)/ALT (SPGT) \</= 2.5 x upper limit of normal (ULN)
* Women (child-bearing potential) and men must use adequate contraception prior to study entry, for duration of study participation, and 90 days after completion of therapy.
* A female of child-bearing potential is any woman is one who has not undergone a hysterectomy or bilateral oophorectomy; or
* Has not been naturally postmenopausal for at least 12 consecutive months
* Ability to understand and the willingness to sign a written informed consent document.

Exclusion Criteria:

* Merkel cell carcinoma
* Leptomeningeal disease or carcinomatous meningitis
* Chemotherapy or radiotherapy within 3 weeks prior to entering the study or those who have not recovered from adverse events due to agents administered \> 3 weeks earlier.
* If the patient was receiving an oral agent, at least 4 half lives should have elapsed.
* Cannot receive any other investigational agent at the time of registration. At least 3 weeks should have elapsed since administration of an IV investigational agent or 4 half lives for an oral investigational agent.
* At least 28 days should have elapsed since administration of a long acting somatostatin analogue.
* Patients with known brain metastases are eligible (see criteria above). Leptomeningeal metastases are not eligible.
* Patients who have received external beam radiation to more than 20% of marrow.
* No prior radiation to the kidneys.
* Prior systemic radiotherapy are not eligible (except for prior I131 for thyroid cancer more than 1 year earlier).
* Receiving long term immunosuppressive medications for rheumatologic or other disease (e.g. low dose methotrexate, mecaptopurine etc).
* History of allergic reactions attributed to compounds of similar chemical or biologic composition to octreotide or other somatostatin analogues.
* Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
* Pregnant or nursing (due to the potential for congenital abnormalities and the potential of this regimen to harm nursing infants.)