I have a skin lump doc! What s next? 12 th August 2017 Dr. Sue-Ann Ho Ju Ee
Some thoughts Is this skin cancer? How common is this? How likely is this in this patient? What happens next if it s something suspicious?
Skin cancer in Singapore 6 th in males 1719 new cases 7 th in females 1381 new cases Trends in Cancer Incidence in Singapore 2010-2014 (Singapore Cancer Registry)
Broadly divided into non melanoma skin cancers (NMSCs) and melanomas NMSCs Basal call carcinomas (BCCs) Squamous cell carcinoma (SCC)
In Singapore, NMSC are much more common than melanoma
In normal population, BCCs > SCCs In solid organ transplant patients, SCCs more common 65-250x more often in transplant patients More aggressive and more likely to metastasize Jensen P, Hansen S, Moller B, et al. Skin cancer in kidney and heart transplant recipients and different long-term immunosuppressive therapy regimens. J Am Acad Dermatol 1999; 40(2 Pt 1):177-86. Hayashida MZ, Fernandes DM, Fernandes DR, et al. Epidemiology and clinical evolution of nonmelanoma skin cancer in renal transplant recipients: a single-center experience in Sao Paulo, Brasil. Int J Dermatol 2015 May 13
RISK FACTORS Fair skin Family history Personal history Lifetime cumulative sun exposure History of tanning Weakened immune system Exposure to radiation Exposure to certain substances eg. Arsenic Smoking Rare genetic disorders eg. Gorlin syndrome, xeroderma pigmentosa
Basal cell carcinoma (nodular) Pearly Translucent Rolled edge Telangiectasia As it grows centre starts to ulcerate Wound that just refuses to heal Usually Slow growing Pigmented variant (common in Asian population)
Distribution Head and neck region, sun exposed areas Do not forget to check behind the ears, under the nose piece of spectacle frames
BCC (MORPHEIC) Ill defined waxy yellow white plaque Poorly defined edges Indurated/ firm to palpation Scar like Areas of ulceration may be visible
High risk NMSC Considered high risk NMSC Poorly defined edges with tumour extending far deeper and wider than what is clinically perceived Much greated morbidity Histologically different from nodular BCC infiltrative strands of BCC Head and neck distribution
SUPERFICIAL BCC Red patch/ thin plaque Focal erosions and crust as enlarge Fine raised edge, more evident on stretching skin Can be multiple Commonly on trunk and extremities
Beware the solitary (discrete multiple) red lesion that doesn t respond to topical steroids
Actinic keratosis Premalignant Multiple rough red scaly papules on sun-exposed sites Initially, slight erythema with impercepticle scale or may just feel scaly (better felt than seen) Background sun damaged skin
Sun exposed site eg. Face, dorsum of hands, bald head, upper back, V of neck Suspicious for malignancy Underlying induration, firm papule/nodule, ulcer Lesions become tender Remove scale to examine
Bowen s disease SCC in situ Slow growing Generally asymptomatic Well defined red scaly plaques May become crusty, eroded Sun exposed sites Lower legs common site eso in women
SCC 2 nd common skin cancer Grows more quickly than BCC Can metastasize so early diagnosis is essentual Mets potential increases with Size Site: lips and ears, sites of scars and repeated inflammation Patient : immune suppressed,
Induration not well defined Nodules, plaques Keratotic Sometimes may see adjacent Bowen s,/ AK Well differentiated SCC Keratotic surface, later ulcerates with eroded margin Poorly differentiated SCC Surface ulceration Look like granulation tissue ** always send for histology PG like lesion in elderly
Poorly differentiated SCC
Cutaneous horn Firm white yellow horn Descriptive term may be viral wart, AK, SCC Examine the base for induration, nodule SCC transformation
RED, BROWN, BLACK
Evolving Surface bleeding New lump from old mole Ulceration Change in sensation Ugly duckling sign
What happens next? Diagnostic punch biopsy or excision biopsy
TREATMENT MODALITIES Topicals 5Fluorouracil Imiquimod Ingenol mebutate Cyrotherapy Surgery Cautery and Curettage Wide local excision Mohs Micrographic Surgery Radiation Therapy Photodynamic therapy Targeted Therapy
Focus on NMSC Most NMSCs can be removed by surgery Depending on size, site and type of skin cancer Wide local excision Mohs Micrographic Surgery
Wide Local Excision 4-5mm margin of clinical evident tumour Assumption that tumour is growing symmetrically in all directions at a similar rate and that safe amount of normal margin is taken all around to ensure clearance
Potential problems Margins of clearance <1% of the surface interface is actually examined Risk of incomplete tumour excision and recurrence Recurrent tumours can be silent, more extensive and difficult to cure
High risk NMSC eg morpheic (infiltrative) BCC or large tumours require 9-10mm margins to achieve adequate clearance Head and neck area sensitive sites with minimal tissue to achieve adequate margin without significant morbidity Difficult to achieve clearance in these sites with these margins risk of recurrence/incomplete removal
More subclinical extension / larger More challenging to treat Higher risk of invasion Recurrent/incomplete excision Functionally or cosmetically unacceptable Increase anxiety Decreased patient satisfaction Higher cost of treatment Increase load on public healthcare
Tumours in the H zone of face are high risk tumours
Mohs Micrographic surgery (MMS) In these cases, MMS is recommended MMS first performed for Dr Frederich Mohs Highly specialized technique Permits the immediate and complete microscopic examination of the removed cancerous tissue, so that all roots and extensions of cancer can be eliminated Allows for removal of as little healthy skin around and below the cancer as possible, which keeps the wound as small possible
Mohs Micrographic surgery
The visible tumour is outlined with a pen with a narrow margin It is removed The tissue is colour coded and a facial map is drawn corresponding to the colour codes. Tissue is processed. It is flattened and cut layer by layer upwards towards the surface so the the whole deep margin and peripheral margin can be visualised The slides are read by the dermatologic surgeon If there are any residual tumous at any point, we can map it out and go in again to specifically remove that area only. This continues until everything is out
Indications for MMS For BCCs : tumors 6 mm in other H zone of the) face; 10 mm in other areas of the face (cheeks, forehead, scalp, and neck); tumors 20 mm on trunk or limbs Adapted from uptodate
Take home message Beware the pyogenic granuloma like lesion presenting as SCC in the elderly (always send for histology) the solitary ( or sometimes multiple discrete) rash that doesn t respond to topical steroids the non healing wounds, repeatedly scabs complaints of pain / tenderness immunesuppressed patient, phototherapy patients, plenty of backgrond sun damage, fair... hidden tissue under the keratosis. ( remove the keratosis to examine underneath for induration, nodule, ulcers)
High risk NMSCs Tumour factors site, size, poorly defined borders, recurrent tumours, incompletely excised tumours, aggressive histology subtype Patient factors Immune suppressed, irradiated pts, genetic conditions predisposing to multiple skin cancers MMS is the treatment of choice for these high risk non melanoma skin cancers
Thank You Sue-ann_ho@nuhs.edu.sg