RSS

Tag Archives: squamous cell carcinoma

Lack of UV-A Protection In Daily Moisturising Creams


Came across another interesting article in the May edition of ‘The Archives of Dermatology’ 2011. The article is entitled ‘Lack of UV-A Protection In Daily Moisturising Creams’ on page 618.

Ultraviolet radiation (UV) contains UVA, UVB and UVC subtypes. The major source of UV exposure for humans is sunlight. The earths ozone layer blocks approximately 98% of all UV radiation and the 2% which reaches the earths surface 99% is of the UVA subtype. UVB can cause direct DNA damage whereas UVA causes indirect damage of DNA via the formation of free radicals. Therefore it is important any sunscreen solution contains both UVA and UVB filters.

This article reported the estimated long-range UVA1 protection of 29 creams.

Major points of note from the article include

– most daily facial creams contain ingredients known as UV filters claiming broad spectrum UV protection

– Sun protection factor (SPF) doesn’t reflect UV-A1 protection

– UVA penetrates window glass whereas UVB is blocked, therefore women working indoors need to protect themselves from UVA exposure

– of the 29 creams 6 didn’t contain any UVA1 filters

I recommend reading the full article as it is an interesting read. Below is a link to the article.

Lack of UV-A Protection in Daily Moisturizing Creams
Steven Q. Wang; Jacqueline M. Goulart; Henry W. Lim
Arch Dermatol. 2011;147(5):618-620

Thanks for reading and I welcome any comments.

Follow me on twitter (@skinpathology)

Keep an eye out for website COMING SOON (www.skinpathonline.com)

Email me with any questions or queries (feedback@skinpathonline.com)

Advertisements
 

Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Cutaneous Squamous Cell Carcinoma – Overview


Squamous cell carcinoma (SCC) is defined by the World Health Organisation as ‘a malignant neoplasm of epidermal (and mucous membrane) keratinocytes in which the component cells show variable squamous differentiation.’

Most SCCs appear on the areas of the skin which get the most sun exposure though this is not the only place which the can arise. SCCs can also arise on mucosal areas such as on the lip. Patients who have a pale complexion and those who do not tan readily are at a greater risk. SCC is very uncommon in the Black population.

The most important causative agent is sun exposure, more correctly UVB radiation. Others factors that have been incriminated include human papilloma virus (HPV) infection, ulcers, immunosuppression and radiotherapy. Patients with organ transplants are also at a greater risk. SCC can be fatal in some cases (most commonly found in Australia) giving rise to the notion that sun exposure, which causes DNA damage and also suppresses the skin immune system, plays a lead role in the cause of aggressive SCCs.

As sun exposure is the major cause factor of SCC, it is no surprise that the forehead, ears, scalp, face, neck, back of the hands and lips are the most common places to find SCCs on the human body.

SCCs commonly appear as plaques/nodules with an elevated/indurated, crusty surface. The areas immediately surrounding the SCC show the typical signs of sun damage.

I have previously blogged about the prognostic factors of SCC, please click on the link to see more (Prognostic Factors of Cutaneous Squamous Cell Carcinoma)

Thanks for reading and I welcome any comments.

Keep an eye out for my website, soon to be up and running (www.skinpathonline.com)

Follow me on twitter (@skinpathology)

 

Tags: , , , , , , , , , , , , , , , , , , , , , , ,

Superficial Basal Cell Carcinoma – A closer look


Superficial basal cell carcinoma (SBCC) is a growth pattern of basal cell carcinoma (BCC) which accounts for approximately 10-30% of all BCCs.

CLINICAL

SBCC presents typically as a reddish (erythematous) patch ranging in size from approximately 3 to >10 mm. They often have a fine pearly border with central superficial erosions. Pale areas within the lesion can be a clue to regression and the lesion may have a history of bleeding. SBCCs are most commonly found on the trunk.

HISTOPATHOLOGY

SBCC is seen as superficial collections of atypical basaloid cells originating from the bottom layer (basal layer, stratum basale) of the epidermis and projecting down into the papillary dermis. These collections are typically surrounded by a loose myxoid (mucin-like) stroma. Although histologically they have an apparent multifocal appearance recent 3D imaging techniques have found that a huge majority of these foci are truly interconnected and therefore not multifocal. Remember SBCC is also usually seen in conjunction with other BCC growth patterns such as nodular and infiltrative.

PROGNOSIS AND TREATMENT

Due to its superficial nature, SBCC has a very good prognosis and there is a wide range of treatments available. SBCC does have a high recurrence rate due to its margins being difficult to assess (this is attributed to its apparent multifocal appearance histologically). Treatments include topical chemotherapy (eg. aldara), photodynamic therapy (PDT) and curettage.

Thanks for reading and I welcome any comments.

Keep an eye out for www.skinpathonline.com COMING SOON

Follow me on twitter (@skinpathology)

 

Tags: , , , , , , , , , , , , , , , , , , , , , ,

Solar Keratosis and It’s Subtypes


Solar Keratosis is defined by the World Health Organization as ‘a common intraepidermal neoplasm of sun-damaged skin characterized by variable atypia of keratinocytes.’

Subtypes that are recognised are hypertrophic, atrophic, acantholytic, pigmented. lichenoid and bowenoid. All subtypes usually display the common features of hypogranulosis, parakeratosis along with keratinocyte atypia confined to the bottom two layers of the epidermis (basal and spinous). Below is some of the histological features commonly seen in the subtypes apart from the features mentioned above.

HYPERTROPHIC

This variant exhibits hyperkeratosis, acanthosis, papillomatosis, rete ridge elongation, telangiectasia and parakeratosis. The parakeratosis can be seen alternating with the hyperkeratosis.

ATROPHIC

This variant exhibits epidermal atrophy, basal epidermal budding with adnexal extension

LICHENOID

This variant exhibits exocytosis, keratinocytic vacuolation, keratinocytic apoptosis, colloid bodies, band-like superficial dermal lymphocytic infiltrate and pigment incontinence.

ACANTHOLYTIC

This variant exhibits acantholysis (with possible extension down adnexae), suprabasal clefting and dyskeratosis.

PIGMENTED

This variant exhibits increased pigmentation of atypical keratinocytes with associated dermal melanophages.

BOWENOID

Although most pathologists consider this Bowen’s disease, some say bowenoid solar keratosis exhibits less than full thickness atypia and sparing of follicles.

Thanks for reading.

Follow me on twitter (@skinpathology)

Keep an eye out for my website www.skinpathonline.com

 

Tags: , , , , , , , , , , , , , , , , , , , , , ,

Basal Cell Carcinoma and It’s Histological Growth Types


Basal cell carcinoma (BCC) is the most common skin malignancy and it’s incidence is on the increase. Below is a description of the four main different histological growth types and what is features are associated with each of them.

Superficial

Superficial BCC presents as a scaly, reddish patch ranging in size from a few mm to over 100mm. Due to this clinical appearance there is often confusion with psoriasis. Superficial BCCs are most commonly found on the trunk and account for 10-30% of all BCCs. Histologically they are characterised by superficial collections of atypical basaloid cells projecting from the epidermis or from the sides of adnexal structures such as hair follicles or eccrine ducts. Due to the 2 dimensional processing of histology specimens most superficial BCCs appear multifocal but recent studies using digital imaging techniques show that the tumours nests are actually all interconnected. Truly multifocal superficial BCCs do occur but these are less common.

Nodular

Nodular BCC most commonly appear as pale, pearly nodules often with macroscopically visible dilated blood vessels coursing over the top of the lesion. Nodular BCCs are most often found on the more sun exposed areas of the body (eg. face and neck). Histologically they are characterised by large, solid lobules of atypical basaloid cells exhibiting a peripheral palisade and often invading as far as the reticular dermis.  Other commons features including the classical BCC retraction artefact and tumour cystic degeneration.

Micronodular

Micronodular BCC most often present as slightly elevated/flat pale lesions. They are most commonly found on the back. Histologically, micronodular BCC appears as an invasive BCC with the tumour islands between 3-10 cells in width (approximately the size of a hair bulb). These smaller tumour islands commonly exhibit perineural invasion. Compared to nodular BCC, the excision margins of micronodular BCC can be more commonly underestimated leading to a higher recurrence rate.

Infiltrating

Infiltrating BCC presents most commonly as an indurated, pale lesion whose clinical margins appear poorly demarcated. They are mostly found on the face and upper trunk. Histologically they appear as diffuse cords, strands, columns of atypical basaloid cells infiltrating deep into the dermis and that rarely exhibit a retraction artefact or peripheral palisade. Due to the highly diffuse infiltrating nature of this tumour perineural invasion is extremely common therefore recurrences are common.

Many thanks for reading and I welcome any comments or questions.

Keep an eye out for www.skinpathonline.com COMING SOON.

My email is feedback@skinpathonline.com for any correspondence.

Follow me on twitter (@skinpathology)

 

Tags: , , , , , , , , , , , , , , , , , , , ,

Prognostic Factors of Cutaneous Squamous Cell Carcinoma


Below is a brief description of the prognostic factors involved with cutaneous squamous cell carcinoma, ie. SCC of the skin.

Site

The actual site of the SCC provides much prognostic information, most importantly that SCCs from sites such as the ear, lip and sole have an increased rate of metastasis.

Size

The physical size of the tumour is also related to prognosis, generally speaking the larger the tumour the poorer the prognosis.

Invasion

If the SCC is seen to be invasive this reflects a poorer prognosis. The actual depth of invasion is again prognostic, ie. the deeper the invasion, the poorer the prognosis.

Tumour differentiation

Histologically SCCs are graded for their differentiation with them being either well, moderately or poorly differentiated. The poorer the tumour differentiation, the poorer the prognosis.

Other

There are many other factors which can affect the prognosis of cutaneous squamous cell carcinoma including immune status of the patient, HPV infection status, age and genetic predisposition.

 

Thanks for reading

Keep an eye out for my website soon to be up and running (www.skinpathonline.com)

Follow me on twitter (@skinpathology)

My email is feedback@skinpathonline.com for any questions or queries.

 

Tags: , , , , , , , , , , , , , , , , , , , ,

Non-melanoma skin cancer (NMSC) treatments


Below are the most common treatments available, plus a brief description, once a NMSC has been diagnosed (usually a basal cell carcinoma or a squamous cell carcinoma).

Surgical excision (standard) – the most common and preferred form of treatment. Good for nodular tumours with a sharply demarcated border. Has a high cure rate and is dependent on the closeness of tumour to the resection margin in regards to the pathology (ie. the closer the tumour is to the margin the more likely it is to recur). One let down is the bread loafing technique which results in only approximately 5% of the actual margins being visualised by the pathologist for assessment of complete excision.

Moh’s /  Moh’s Micrographic Surgery – form of treatment with the highest reported cure rate (~97-99%). This technique results in the entire peripheral margins and the deep margins being visualised and assessed for completeness of excision (this is why the cure rate is so high). One let down is the time-consuming nature of the technique and the specialised training that is involved.

Topical chemotherapy – the most common available topical chemotherapy agents include 5-fluorouracil (5-FU) and 5% imiquimod. Generally speaking 5-FU works by inhibiting DNA replication therefore the growth of the tumour and imiquimod works by modifying the local tumour immune response of the patient. Advantages include the non-invasiveness topical therapy. Disadvantages are that, used alone, they can only be used on superficial tumours and not invasive tumours. Experimentation of their use in conjunction with other treatments (eg. curettage then topical treatment, or topical use to reduce tumour size before excision) have resulted in reports of higher cure rates.

Curettage +/- Electrodissection – put simply the tumour is physically scrapped away then the treated area is exposed to an electrical current which results in the softening of the skin and the procedure is repeated until the treating physician is satisfied excision is complete. The curettage portion technique can be applied alone without the electrodissection. This technique is usually reserved for site which are cosmetically unimportant (eg back). The cure rate is dependent on how aggressive the technique is applied (ie. the more the aggressive the higher the cure rate) and the growth type of the tumour being treated (ie. the more invasive the tumour the lower the cure rate).

Cryotherapy – one of the older treaments for NMSC which involves treatment of the tumour most commonly with liquid nitrogen. Cure rate can be high but there is reduced tumour margin control resulting in a higher recurrence rate.

Photodynamic Therapy (PDT) – fairly new technique which involves applying a topical photosensitizer to the target tumour and then exposure of the target area to light. This results in the production of aggressive chemicals which damage the cell causing death. Disadvantages include the ineffectiveness on invasive and thicker tumours due to lack of light penetration, and high cost. Advantages include the non-invasiveness of the technique.

Radiotherapy – usually reserved for older patients or where the surgical removal of the tumour is not a viable option. Has a reported cure rate of approximately 80-95%. Tumours recurring after radiotherapy are generally more aggressive and can become radiotherapy resistant.

I welcome any comments or other therapies you have encountered.

Keep and eye out for www.skinpathonline.com.

Follow me on twitter (@skinpathology)

 

Tags: , , , , , , , , , , , , , , , , , , , ,