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, current health topics, and expertise on managing health. Click here for an email preview.

We use the data you provide to deliver you the content you requested. To provide you with the most relevant and helpful information, we may combine your email and website data with other information we have about you. If you are a Mayo Clinic patient, we will only use your protected health information as outlined in our Notice of Privacy Practices. You may opt out of email communications at any time by clicking on the unsubscribe link in the email.

Aug. 26, 2022 See more Expert Answers

See also

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