Basal cell carcinoma

Basal cell carcinoma 

Updated: 03/17/2021

© Jun Wang, MD, PhD

General features
  • Most common skin cancer
  • Usually > 40 years of age
  • Multiple BCCs may develop early if nevoid basal cell carcinoma syndrome
  • Mainly sun exposed skin, especially hair-bearing areas
  • Slow growing, rarely metastasize
Risk factors
  • Exposure to natural and artificial ultraviolet light
  • Radiation
  • Gene mutations
  • Existing actinic keratosis
  • Arsenic exposure, immunosuppression, albinism, alcohol, xeroderma pigmentosum
Key pathogenesis
  • UV
UVB: most carcinogenic, absorbed by DNA
DNA damage and p53 mutation
  • DNA mismatch repair defect
  • PTCH mutation
Hedgehog pathway
Causes loss of inhibition of SMO, results in constant activation
Seen in nevoidbasal cell carcinoma syndrome, sporadic basal cell carcinomas and Xeroderma pigmentosum associated basal cell carcinoma
Clinical features
Key pathological features
Multifocal growth
Irregular budding from basal layer
  • Nodular type
Nodular growth of tumor cells
  • Morpheaform
Irregular cords or nests of tumor cells
Fibrotic stroma
Higher recurrence rate
Likely perineural invasion
Mohs surgery indicated
  • Other variant: basasquamous cell carcinoma, clear cell type, etc
Management
  • Excision
  • Radiation
  • Photodynamic therapy
  • Hedgehog pathway inhibitors



Back to skin tumors
Back to contents

Comments

Post a Comment

Popular posts from this blog

Contents

Pathology notes Jun Wang, MD, PhD 1. General information Frequently discussed syndromes Terms of dermatology Terms of hematology 2. Primary immunodeficiency disorders 3. Hemodynamic abnormalities Shock Thrombosis and embolism Bleeding disorders 4. Benign white cell disorders 5. Hematopoietic neoplasms Lymphoid neoplasms Myeloid neoplasms Histiocytic neoplasms: Langerhans cell histiocytosis 6. Cardiovascular system Pulmonary hypertension Cardiovascular system tumors 7. Respiratory tract tumors 8. Gastrointestinal tract Congenital disorders Infectious gastroenteritis Oral cavity Esophagus Stomach Intestinal tumors Salivary glands Exocrine pancreas and gallbladder 9. Urinary system Kidney masses Lower urinary tract 10. Male reproductive system 11. Female genital tract 12. Breast 13. Endocrine organs Pituitary gland Adrenal gland Thyroid gland Parathyroid gland Endocrine pancreas Multiple endocrine neoplasms 14. B
Read more

Female genital tract

Pathology of female genital tract   Updated: 01/23/2024 © Jun Wang, MD, PhD Key anatomic features Opened channel, pathological basis for pelvic inflammatory disease Cervix: exocervix, endocervix, transformation zone Uterus: fundus, body Fallopian tube: intramural, isthmus, ampulla, infundibulum, fimbriae Placenta: umbilical cord, fetal membrane, placenta Key histologic features Stratified squamous epithelium from vulva to exocervix Simple columnar epithelium from endocervix to fimbriae Uterine corpus Endometrium: Glands, stroma Myometrium Perimetrium: Mesothelium/peritoneum Ovaries: three components Epithelium (mesothelium) Stroma Germ cells (follicles) Placenta: Cytotrophoblast, syncytiotrophoblast, intermediate trophoblast Infectious/inflammatory diseases Diseases of vagina and vulva Molluscum contagiosum Lichen sclerosus Paget disease Sarcoma botryoides Squamous cell carcinoma Diseases of cervix Cervical intraepithelial neopla
Read more

Neoplasms of respiratory tract

Neoplasms of respiratory tract   Updated: 11/14/2022 © Jun Wang, MD, PhD Anatomy Nasal cavity Nasopharynx Oropharynx Laryngopharynx Larynx Trachea and bronchi Lungs Histology Squamous mucosa Respiratory mucosa May have abundant lymphoid tissue in pharynx Type I and Type II pneumocytes Key risk factors Human papillomavirus: Squamous cell carcinoma, squamous cell papilloma Epstein Barr virus: Nasopharyngeal carcinoma Smoking Tumors of nasal cavity and nasopharynx Olfactory neuroblastoma Nasopharyngeal angiofibroma Sinonasal papilloma NUT midline carcinoma Nasopharyngeal carcinoma Tumors or tumor like lesions of larynx Vocal cord polyp Squamous papilloma Squamous cell carcinoma Branchial pouch/cleft anomalies Branchial cyst Thyroglossal duct cyst Neoplasms of lung Squamous cell carcinoma Adenocarcinoma Large cell carcinoma Small cell carcinoma Carcinoid Lymphangioleiomyomatosis Neoplasms of pleura Mesothelioma
Read more