Penile Flashcards
Anatomy
Anterior to rectum and anus
Inferior to bladder and pubic bone
Partially interior and exterior
Superifcial to deep structure: 1. Skin, 2. Superficial fascia, 3. Areolar tissue, 4. Deep fascia 5. Tunica albuginea 6. Corpus cavernosum/spongiosum
Epidemiology
Uncommon in west
Common in SE Asia, India, Africa - second most common male cancer in Uganda
Increased risk after 55
Aetiology
Hygiene
Phimosis (tight foreskin cannot be pulled back over head of penis) (50% of cases)
Chronic inflammatory conditions
Tobacco
History of genital condylomata
Premalignant conditions: bowens disease, pagets disease
HPV
Patterns of spread
Local: wide surface extension, deeper invasion, urethra, corpora cavernosa
Lymphatic: early to inguinal and regional pelvic nodes, inguinal spread can ulcerate ->para-aortic
Distant: uncommon: prostate and bladder using direct seeding
Blood borne to skin, lungs, bone
Histology
SCC - well differentiated (Related to AIDS)
Others: BCC, melanoma, Karposi’s sarcoma
Staging
Tis - carcinoma in sity
Ta- non invasive verrucous carcinoma
T1 - tumour invades subepithelial connective tissue
T2- tumour invades corpus spongiosum or cavernosum
T3- Tumour invades urethra
T4 - Tumour invades other adjacent structures
RT treatment technique
Primary lesion: opposed pair, lateral fields
Bolus to cover top of penis - required to achieve uniform dose around area
High stage or Nodal: Opposed pair (a/p), multiple field conformal, IMRT
Clinical Management
Surgery : total excision, small lesions: cryosurgery, laser. Deeper lesion: wider excision, partial or full amputation. Nodal involvement: block dissemination
Radiotherapy: brachytherapy(iridium implants 60-65Gy over 6-7 days), EBRT
Chemo: very limited (bleomycin, 5FU, Methotrexate, cisplatin)
Very poor prognosis without treatment
Good 5 year survival with treatment
OARs
Rectum
Small bowel
EBRT volumes and doses
Superficial XRT (100-250kV) - primary lesion, 50Gy in 15# to primary lesion
MV photons: whole shaft 50-55Gy in 20# or 60Gy in 30# Up to 74Gy in 37#
Palliative: 30Gy in 10#
Nodal treatment: Bilateral inguinal and pelvic node irradiation
Signs and symptoms
Obvious visible mass, ulceration and bleeding, gland or inner surface of prepuce, discharge, pain
Patient setup
Hands on chest, headrest, supine, block, foot bolster, knee separation, vacbag
Acute side effects
Skin reaction - erythema (cream, loose clothing, salt water bathing), subcutaneous swelling - discomfort, moist desquamation- infection, urinary discomfort/dysuria, diarrhoea, psychosocial impact
Late Side effects
Telangiectasia and fibrosis, ulceration or tissue necrosis, urethral stricture, erectile impotence, psychosocial impact
Nodal dose fraction
no gross disease: 50 in 25#
palpable disease: 60 in 30#
