Inclusion Criteria:

- Pure or mixed variant urothelial carcinoma o Allowable mixed variant subtypes
include: squamous differentiation glandular differentiation nested pattern
microcystic micropapillary lymphoepthelioma-like plasmacytoid and lymphoma-like
sarcomatoid/carcinosarcoma giant cell trophoblastic differentiation clear cell lipid
cell undifferentiated Radical cystectomy and pelvic lymph node dissection within the
prior 48 weeks Pathologic T3 or higher stage disease, N0-2, M0 (AJCC, 7th Ed.,
Appendix C) No clinical evidence of residual or recurrent disease based on the
following minimum diagnostic work-up within 8 weeks of a patients consent to
participate.

- History and physical examination

- Chest imaging by x-ray (PA and lateral views) or CT scan (with or without IV
contrast);

- Axial abdominal and pelvic imaging by MRI (preferably with gadolinium)

- Bone scan

- Patients with microscopically involved (positive) surgical margins, but no
grossly evident residual disease by imaging or physical exam are eligible.

The patient is a candidate for definitive external beam radiotherapy;

- No prior radiotherapy to the region of study;

- No inflammatory bowel disease, active collagen vascular or connective tissue
disorders, and no other medical or social contraindications to radiotherapy, as
determined by a participating radiation oncologist; Age ³18 years ECOG performance
status: 0-2 Concurrent noninvestigational medications will be permitted Informed
consent: Patients must have the ability to understand and be willing to sign the
study-specific informed consent indicating their understanding of the investigational
nature and the risks of this study before any of the protocol related studies are
preformed (this does not include routine laboratory testing or imaging studies
required to establish study eligibility);

Exclusion Criteria:

- Unstable renal function in the month prior to registration defined as a creatinine
rise of 1 mg/dL Prior partial or complete small bowel obstruction either before or
after radical cystectomy Prior radiotherapy to the pelvis; o Prior radiation therapy
for a different cancer or disease process is allowed, provided there will be no
overlap of radiation therapy fields between the participants prior and current course
of radiation therapy, radiotherapy was completed more than four weeks from enrolling
in this study.

Planned concurrent chemotherapy or other investigational drug to be given with radiation
treatments o Prior chemotherapy or investigational drug for bladder cancer or a different
cancer is allowed, provided that: The therapy was completed more than two weeks prior to
the start of adjuvant pelvic radiation The participant has recovered to Grade 1 toxicity
from agents previously administered Subtotal surgical resection with clinically evident
residual disease by physical exam or axial imaging.

Prior or concurrent second invasive malignancy other than prostate and non-melanoma skin
cancers, unless disease free for a minimum of five years. If a patient had a concurrent
prostate cancer, then it must have been resected to negative margins.

Known severe, active co-morbidity, defined as follows:

o Any clinically significant unrelated systemic illness, medical condition, or other
factor, which at the discretion of the Principal Investigators, would interfere in the
safe and timely completion of study procedures, compromise the patients ability to
tolerate the protocol therapy, or is likely to interfere with the study procedures or
results.