Why are some cancers described as small cell and some as large cell? What do these terms mean?

Answer From Edward T. Creagan, M.D.

The terms "small cell" and "large cell" describe what cancer cells look like under a microscope.

Looking at the cancer cells and noting their size and shape gives your health care team helpful clues about your diagnosis. It helps your care team figure out the type of cancer you have and where the cancer began. A careful study of the cancer cells can also show how much the cells have changed compared to healthy cells.

Your health care team uses this information along with test results for the size and spread of the cancer to determine:

  • The likely course or outcome of the cancer, which is also called the prognosis
  • The best treatment for a certain cancer
  • Whether surgery is an option

Terms used to describe what cancer cells look like under a microscope include:

  • Clear cell. The inside of the cell seems clear. Cancers with clear cells include some kidney, ovarian and uterine cancers.
  • Spindle cell. The cell is narrower at both ends than at the middle. Cancers with spindle cells include some breast, gastrointestinal, muscle or other soft tissue, and skin cancers.
  • Large cell. The cell is larger than a typical cell. Cancers with large cells include some types of lung cancer and lymphoma.
  • Small cell. The cell is smaller than a typical cell. Cancers with small cells include some types of lung cancer, prostate cancer and pancreatic neuroendocrine tumors. Sometimes these cancers are called small round cell cancers.
  • Squamous cell. The cell looks flat. In the body, these cells are often arranged like tiles on a floor. Squamous cell cancers include some types of skin cancer and some types of cancer that start in the lining of organs, such as the bladder.
  • Adenocarcinoma. The cell looks like a gland cell. Cancers with this type of cell include some types of breast, prostate, lung, gastric and endometrial cancers.
  • Anaplastic. The cell looks very irregular. These cells may have an unusual size and may not resemble any typical cells. It may be hard to tell where these cells come from.
  • Metaplastic. The cell has many different looks. Metaplastic cancers are made up of many different types of cells that look different from each other.
  • Poorly differentiated. The cell appears very irregular. In typical tissue, cells in a certain area look different from cells in another area. For example, breast cells look different from colon cells. If cells look very unlike typical cells, they are considered poorly differentiated. In general, these cancers may be aggressive.

Other factors that help classify a cancer include:

  • Part of the body in which the cancer started. Cancers are named for where they start. For example, if breast cancer spreads into the liver, it is still called breast cancer.
  • Type of tissue from which the cancer started. Some terms used to describe cells can tell you about where the cancer started. For example, carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer of the bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

With

Edward T. Creagan, M.D.

Follow on Twitter: @EdwardCreagan

From Mayo Clinic to your inbox

Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health. Click here for an email preview.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

Aug. 26, 2022 See more Expert Answers

See also

  1. Infographic: 3D Printing for Cancer Treatment
  2. Adjuvant therapy for cancer
  3. Alternative cancer treatments: 11 options to consider
  4. Atypical cells: Are they cancer?
  5. Biological therapy for cancer
  6. Biopsy procedures
  7. Blood Basics
  8. Bone marrow transplant
  9. Bone scan
  10. Cancer
  11. Cancer
  12. Cancer blood tests
  13. Myths about cancer causes
  14. Infographic: Cancer Clinical Trials Offer Many Benefits
  15. Cancer diagnosis: 11 tips for coping
  16. Cancer-related fatigue
  17. Cancer pain: Relief is possible
  18. Cancer-prevention strategies
  19. Cancer risk: What the numbers mean
  20. Cancer surgery
  21. Cancer survival rate
  22. Cancer survivors: Care for your body after treatment
  23. Cancer survivors: Late effects of cancer treatment
  24. Cancer survivors: Managing your emotions after cancer treatment
  25. Cancer survivorship program
  26. Cancer treatment
  27. Cancer treatment decisions: 5 steps to help you decide
  28. Cancer treatment myths
  29. Cancer-related fatigue
  30. Cancer-related pain
  31. Cancer-related weakness
  32. Chemo Targets
  33. Chemoembolization
  34. Chemotherapy
  35. Chemotherapy and hair loss: What to expect during treatment
  36. Chemotherapy and sex: Is sexual activity OK during treatment?
  37. Chemotherapy nausea and vomiting: Prevention is best defense
  38. Chemotherapy side effects: A cause of heart disease?
  39. Complete blood count (CBC)
  40. Cough
  41. CT scan
  42. Curcumin: Can it slow cancer growth?
  43. Cancer-related diarrhea
  44. Eating during cancer treatment: Tips to make food tastier
  45. Fatigue
  46. Fertility preservation
  47. Heart cancer: Is there such a thing?
  48. High-dose vitamin C: Can it kill cancer cells?
  49. Honey: An effective cough remedy?
  50. Infographic: CAR-T Cell Therapy
  51. Intensity-modulated radiation therapy (IMRT)
  52. Intrathecal chemotherapy
  53. Joint pain
  54. Low blood counts
  55. Magic mouthwash
  56. Medical marijuana
  57. Microwave ablation for cancer
  58. Mindfulness exercises
  59. Minimally invasive cancer surgery
  60. Monoclonal antibody drugs
  61. Mort Crim and Cancer
  62. Mouth sores caused by cancer treatment: How to cope
  63. MRI
  64. Muscle pain
  65. Needle biopsy
  66. Night sweats
  67. No appetite? How to get nutrition during cancer treatment
  68. Palliative care
  69. PALS (Pets Are Loving Support)
  70. Pelvic exenteration
  71. PET/MRI scan
  72. Radiation therapy
  73. Infographic: Scalp Cooling Therapy for Cancer
  74. Seeing inside the heart with MRI
  75. Self-Image During Cancer
  76. Sentinel lymph node mapping
  77. Sisters' Bone Marrow Transplant
  78. Sleep tips
  79. Mediterranean diet
  80. Radiation simulation
  81. Stem Cells 101
  82. Stem cells: What they are and what they do
  83. Thalidomide: Research advances in cancer and other conditions
  84. Tumor vs. cyst: What's the difference?
  85. TVEC (Talimogene laherparepvec) injection
  86. Ultrasound
  87. Unexplained weight loss
  88. Stem cell transplant
  89. How cancer spreads
  90. MRI
  91. PICC line placement
  92. When cancer returns: How to cope with cancer recurrence
  93. Wide local skin excision
  94. X-ray