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• Advanced Malignancies
• Antiphospholipid
• Breast
• Cancer Prevention
• Cancers of the Digestive Tract
• Chronic Myelogenous Leukemia

  Chronic Lymphocytic Leukemia (CLL): Introduction

  Leukemia is cancer that starts in the bone marrow. This is where new blood cells are made. Chronic lymphocytic leukemia (CLL) is a type of leukemia that starts in the lymphoid cells in the bone marrow. These are cells that normally help the body fight infection. 
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• Colorectal (colon, rectum and anus)
• Esophageal Cancer

  Esophageal Cancer: Introduction

  Esophageal cancer is cancer that starts in your esophagus. This is the tube that carries food and liquid from your throat to your stomach.
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• Gastric Cancer
• Gastrointestinal Malignancies
• General Gynecology

  Gynecological Conditions

  Many different gynecological conditions require the care of a health care provider. Learn detailed information on the most common gynecological conditions including Recognizing Gynecologic Problems, Endometriosis, Pelvic Pain, Polycystic Ovarian Syndrome, Sexually Transmitted Diseases, Uterine Fibroids, Pap Test and Safer Sex Guidelines.
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• General Hematology

  Hematology

  Hematology is the study of blood and blood disorders. Hematologists and hematopathologists are highly trained healthcare providers who specialize in diseases of the blood and blood components. These include blood and bone marrow cells. Hematological tests can help diagnose anemia, infection, hemophilia, blood-clotting disorders, and leukemia.
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• General Oncology

  Cancer Overview

  Cancer cells don't function properly, and they can spread to many areas of the body. Tumors are clusters of cells that are capable of growing and dividing uncontrollably; their growth is not regulated.
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• Genitourinary

  Home Page - Genitourinary and Kidney Disorders

  Learn more about genitourinary and kidney disorders in children, including Anatomy of the Urinary System, Overview of Kidney Disorders.
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• Geriatric Breast Cancer

  BRCA

  The BRCA genes are the most common cause of gene-related breast and ovarian cancers. In the U.S., 1 in 20 to 1 in 10 of all breast cancers and 1 in 10 to 3 in 20 of all ovarian cancers in white women are related to BRCA mutations. This blood test checks for mutations.
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• Geriatric Lung Cancer

  Lung Cancer: Introduction

  Lung cancer is cancer that starts in the lungs. Lung cancer is divided into two main types: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). These types grow and spread differently. They are often treated in different ways.
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• Gynecologic Oncology

  Gynecological Cancers

  Detailed information on the most common types of gynecological cancers, including symptoms, risk factors, diagnosis, and treatment. There are several different types of gynecological cancer require the care of a health care provider. A brief overview of Cervical Cancer, Endometrial Cancer, Ovarian Cancer, Uterine Cancer, Vaginal Cancer, Vulvar Cancer is provided.
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• Head and Neck Cancers

  Head and Neck Cancer: Introduction

  Head and neck cancer is the term given to cancers that start in the head and neck region. There are many different types of tissues in this area.  Your healthcare provider can help you understand more about this cancer and the exact type you have.
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• Hepatobiliary Cancers
• Laryngeal Cancer

  Laryngeal Cancer: Introduction

  Laryngeal cancer occurs when normal cells change and grow uncontrollably. These cells form a cancerous tumor in the larynx or voice box, which is located in your neck.
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• Liver Cancer

  Liver Cancer: Introduction

  Cancer is when cells in the body change and grow out of control. Liver cancer is cancer that starts in your liver. Several types of non-cancerous (benign) tumors can also form in the liver. These include hemangiomas, hepatic adenomas, and focal nodular hyperplasia.
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• Lung
• Lung Cancer

  Lung Cancer: Introduction

  Lung cancer is cancer that starts in the lungs. Lung cancer is divided into two main types: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). These types grow and spread differently. They are often treated in different ways.
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• Lung Cancer & Chest Malignancies

  Lung Cancer: Introduction

  Lung cancer is cancer that starts in the lungs. Lung cancer is divided into two main types: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). These types grow and spread differently. They are often treated in different ways.
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• Lymphoma

  Lymphomas

  There are many types of lymphomas that require clinical care by a physician or other healthcare professional. Detailed information on lymphomas, including Hodgkin's lymphoma and non-Hodgkin's lymphoma.
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• Melanoma

  Melanoma: Diagnosis

  If your healthcare provider thinks you might have melanoma, you will likely need certain exams and tests to be sure. Your healthcare provider will take a close look at any suspicious moles or other marks on your skin. 
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• Multiple Myeloma

  Multiple Myeloma: Introduction

  Multiple myeloma is cancer that starts in your bone marrow. Specifically, it starts in plasma cells. In multiple myeloma, normal plasma cells go through a series of changes. This can eventually cause excess cell growth. It can also cause tumors to form in your bones.
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• Ovarian Cancer

  Ovarian Cancer: Introduction

  Many types of tumors can start growing in the ovaries. Some are benign. This means that they’re not cancer. Benign tumors don’t spread. They can usually be treated by removing one ovary or part of the ovary. Ovarian cancer, however, is a malignant (cancerous) tumor. If a cancerous tumor isn’t treated, it can grow and spread to other parts of your body.
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• Pancreas

  Pancreas

  The pancreas is involved in blood sugar control and metabolism within the body, and also in the secretion of substances (collectively pancreatic juice) which help digestion. Detailed anatomical description of human pancreas, including simple definitions and labeled, full-color illustrations.
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• Pancreatic Cancer

  Pancreatic Cancer: Introduction

  Pancreatic cancer often grows within the pancreas for a long time before it causes any symptoms. If the cancer grows outside the pancreas, it often goes into the nearby bile ducts and lymph nodes in your belly (abdomen). In some cases, it spreads to other nearby areas.
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• Prostate Cancer

  Prostate Cancer: Introduction

  Prostate cancer is the most common cancer in men (not counting skin cancer) in the U.S. It tends to occur mainly in older men. In most cases prostate cancer is found before it has spread to other parts of the body. Cancer that hasn’t spread is easier to treat and cure.
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• Renal Cancer

  Kidney (Renal) Cancer: Introduction

  A kidney is made up of many layers of cells. Kidney cancer can affect any one or all of these layers. The cancer can stop the kidneys from working normally. Kidney cancer may spread to other parts of the body. When cancer spreads, it’s called metastasis. 
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• Sickle Cell Anemia

  Autosomal Recessive: Cystic Fibrosis, Sickle Cell Anemia, Tay Sachs Disease

  Mutations (or changes in the DNA) have occurred over time in different parts of the world. Anyone can carry any type of recessive gene. However, certain ethnic groups are more likely to carry certain recessive genes, because of where the mutation originated. Overview of autosomal recessive inheritance, including cystic fibrosis, sickle cell anemia, and Tay Sachs disease.
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• Testicular Cancer

  Testicular Cancer: Introduction

  Cancer that develops in a testicle is called testicular cancer. It is one of the most curable forms of cancer.
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• Thoracic Cancer

  Lung Cancer: Introduction

  Lung cancer is cancer that starts in the lungs. Lung cancer is divided into two main types: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). These types grow and spread differently. They are often treated in different ways.
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• Unknown Primary

  Cancer of Unknown Primary: Introduction

  Cancer of unknown primary (CUP) is cancer that starts in an unknown area and has already spread by the time it's diagnosed.
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• Waldenstrom's Disease

  Non-Hodgkin Lymphoma: Introduction

  Lymphoma is a kind of cancer that starts in the lymphatic system. In non-Hodgkin lymphoma, cells in the lymphatic system grow out of control. Learn more about many of the types and subtypes of non-Hodgkin lymphoma.
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• Breast Cancer
• Treating side effects of cancer therapy

1. Evaluation of an NP-based model of palliative care delivery within an oncology clinic. Sarah F. DAmbruoso, Neil Wenger, Anne Coscarelli, Sara A. Hurvitz, Christopher Pietras, Meghan Nechrebecki, Jennie Kung, Rena Desai Callahan, Jonathan Wade Goldman, Parvin F. Peddi, Drakaki Alexandra, Samuel A. Skootsky, and Anne Margaret Walling Journal of Clinical Oncology20173531_suppl163-163
2. R J Hartmaier, S E Trabucco, N Priedigkeit, J H Chung, C A Parachoniak, P Vanden Borre, S Morley, M Rosenzweig, L M Gay, M E Goldberg, J Suh, S M Ali, J Ross, B Leyland-Jones, B Young, C Williams, B Park, M Tsai, B Haley, J Peguero, R D Callahan, I Sachelarie, J Cho, J M Atkinson, A Bahreini, A M Nagle, S L Puhalla, R J Watters, Z Erdogan-Yildirim, L Cao, S Oesterreich, A Mathew, P C Lucas, N E Davidson, A M Brufsky, G M Frampton, P J Stephens, J Chmielecki, A V Lee; Recurrent hyperactive ESR1 fusion proteins in endocrine therapy-resistant breast cancer, Annals of Oncology, Volume 29, Issue 4, 1 April 2018, Pages 872–880, https://doi.org/10.1093/annonc/mdy025
3. Jennifer S. Woo, Neda A. Moatamed, Peggy S. Sullivan, David Y. Lu, Rena Callahan et al. (2015) Comparison of Phosphohistone H3 Immunohistochemical Staining, Ki-67, and H&E Mitotic Count in Invasive Breast Carcinoma. Journal Of Breast Cancer Survival - 1(1):1-11.
4. Ponec, R., Peddi, P., Callahan, R. "Parp inhibitors in Breast Cancer: Latest Evidence." Current Breast Cancer Reports. Vol 9, 2017.
5. Rena Callahan. Ado-Trastuzumab Emtansine in Metastatic HER2-Positive Breast Cancer. J Adv Pract Oncol. 2014 Mar-Apr; 5(2): 134–139.
6. Rena D. Callahan, Patricia A. Ganz. “Side Effects of Systemic Therapy: Neurocognitive, Cardiac, and Secondary Malignancies.” Diseases of the Breast, 5th edition, Ed. Jay R. Harris, MD, Marc E. Lippman, MD, Monica Morrow, MD, and C. Kent Osborne, MD. Lippincott Williams and Wilkins, May 2014, 1224. ISBN: 978-1-4511-8627-7.
7. RD Callahan, SA Hurvitz. HER2-Positive Breast Cancer: Current Management of Early, Advanced, and Recurrent Disease. Current Opinions in Obstetrics and Gynecology, 2011 Feb. 23 (1):37-43.
8. R.Callahan, R. Patel, D.Chan, M.Allison, B. Dicarlo, L. Bosserman, A. Kennedy, L.M. Zehngebot, J. Miller, A.E. Giuliano, B. Spivack, L.S. Lin, D.J. Slamon, S.A. Hurvitz. Phase II Trial of Presurgical Treatment with Trastuzumab (H) or Lapatinib (Ty) or the Combination of Trastuzumab and Lapatinib (H+Ty), Followed by Six Cycles of Docetaxel (T) and Carboplatin (C) with Trastuzumab (TCH) or Lapatinib (TCTy) or the combination of Trastuzumab and Lapatinib (TCHTy) in Patients with HER2+ Breast Cancer. 2010 San Antonio Breast Cancer Symposium, December 2010.
9. Richard P. Tonino, Pierre J. Meunier, Ronald Emkey, Jose A. Rodriguez-Portales, Charles-Joel Menkes, Richard D. Wasnich, Henry G. Bone, Arthur C. Santora, Mei Wu, Rena Desai, and Philip D. Ross. “Skeletal benefits of Alendronate: 7-Year Treatment of Postmenopausal Osteoporotic Women.” J. Clin. Endocrinol. Metab. 2000. 85: 3109-3115.
10. Rena Desai Callahan, K. Rajender Reddy. “Liver Disease in Pregnancy.” The Clinician’s Guide to Liver Disease. Ed. Reddy KR and Faust T. Philadelphia: Slack, 2006: 211-230.
11. Richard P. Tonino, Pierre J. Meunier, Ronald Emkey, Jose A. Rodriguez-Portales, Charles-Joel Menkes, Richard D. Wasnich, Henry G. Bone, Arthur C. Santora, Mei Wu, Rena Desai, and Philip D. Ross. “Efficacy and Tolerability of Alendronate (7 years), and Effect of Discontinuation.” The 8th Annual Congress on Women’s Health and Gender Based Medicine, Hilton Head, SC, June 2000.
12. Rena Desai, Kirti Shetty, Kim M. Olthoff, Abraham Shaked, Colleen M. Brensinger, K. Rajender Reddy. The Tokyo Score in the Prognosis of Hepatocellular Carcinoma. Young Investigator’s Forum, Controversies in Transplantation. March 2004.
13. Christopher Gasink, Stephen Rulyak, Stephen Rubesin, Rena Desai, James Lewis, Bernard Birnbaum, Jill E. Jacobs, Matthew Gardiner, Gary R. Lichtenstein. Ileal Thickening: Radiographic Features Predictive of Crohn's Disease on Abdominal CT Scan. Digestive Disease Week, May 2004.
14. Rena Callahan, Ashkan Lashkari, Baldeep Singh. Myositis Ossificans. Society for General Internal Medicine Annual Meeting, March 2006.

Winter 2016 Ask the Expert: Neoadjuvant Therapy - (lbbc.org)
The science of why human breasts are so big - (businessinsider.com)

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• Super Doctors southern california rising stars (2018, 2017, 2016 
• Henry Mayo Newhall Hospital Foundation, "Healthcare Hero" 2018, 2017, 2016, 2015 
• Commendation for Excellence in Medical Student Teaching, UCLA, 2007
• Commendation for Excellence in Medical Student Teaching, UCLA, 2006
• Commendation for Excellence in Medical Student Teaching, UCLA, 2005
• Russell J. Stumacher Memorial Award, for academic and artistic excellence, University of Pennsylvania School of Medicine, 2004
• Glasgow Rubin Award, for academic excellence, University of Pennsylvania School of Medicine, 2004
• Alpha Omega Alpha medical honor society, inducted 2003 
• Yale Class of 1956, Summer Fellowship for Study Abroad, 1996

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