Search Results

This chapter reviews the epidemiology of cutaneous and ocular melanomas. Cutaneous melanoma is the most lethal form of skin cancer. There were an estimated 160,000 new cases diagnosed worldwide in 2002, more than 80% in developed countries, and 41,000 deaths, 66% in developing countries. Sun exposure is its major cause, although a variety of phenotypic and genotypic characteristics contribute substantially to the risk of this complex disease. Ocular melanoma is globally much less significant than cutaneous melanoma and shows little current evidence of uptrend in incidence, in contrast to the continuing uptrend in melanoma. Melanocytes that give risk to ocular melanomas lie principally in pigmentary epithelia that extend continuously from the choroid, a vascular membrane that separates the neural elements of the retina from the fibrous outer covering of the eye (the sclera), anteriorly to the ciliary body and iris.

This chapter discusses skin and soft tissue tumours. Three known skin tumours are the basal cell carcinoma, the squamous cell carcinoma, and the melanoma. Basal cell carcinoma or rodent ulcer predominantly affects the elderly and is rarely a clinical problem except in a few neglected cases and in cases where there is an extensive invasion of the local soft tissues and bones. Squamous carcinoma emerges in middle-aged and elderly patients. Compared to basal cell carcinoma, squamous carcinoma spreads in the local and regional nodes and may develop blood-borne metastases. Melanoma, the most potent of the three skin tumours affects any age, although it is rare in children. It is associated with excessive sun exposure. This disease has rapid blood-borne metastases and can cause rapid death.

This chapter explores the effects that psychosocial interventions can have on cancer prognosis. The results of major studies that examined the impact of psychosocial and behavioral interventions on survival in patients with breast cancer and malignant melanoma respectively are discussed, along with the immune mechanisms that may be involved in the remarkable effects observed. The role of religion and spirituality as elements of psychosocial support in the support, treatment and prognosis of cancer patients is also considered, together with the relationship between stress, endocrine function, and cancer progression. There seems to be a convergence of evidence that factors involved in religious and spiritual belief, including meaning, purpose and hope in life, and social support, may have beneficial effects on how well and even how long people live with cancer.

The predominant carcinogen for all three forms of skin cancer is ultraviolet radiation via sun exposure. Personal susceptibility factors include fair hair and skin, and a tendency to burn and not tan. In theory, skin cancers in fair-skinned people are substantially preventable by avoiding UV radiation exposure. Behavior modification programs have been remarkably successful in some countries, for instance the “Slip (on a shirt), Slap (on a hat), and Slop (on sunscreen)” campaign on Australia. In the coming decades, the extent to which these programs translate into a lower incidence of skin cancer will become apparent.

This chapter focuses on the ozone layer present in the lower stratosphere and its biological significance. The ozone is created and destroyed by ultraviolet radiation from the sun. Various natural phenomena, such as volcanic eruptions and the emmission of chemicals such as chlorofluorocarbons (CFCs), also disturb the ozone layer, resulting in an ozone hole. A decline in stratosphere ozone levels increase terrestrial ultraviolet radiation. The chapter also explores ultraviolet radiation and its biological effects and its effects on agricultural yields, the eco-system, and amphibian species. Ultraviolet light promotes a synthesis of vitamin D, which has a beneficial effect on human health. The mechanisms of all the other effects, which are negative and lead to cortical cataracts, skin cancer, melanoma, and sunburn; DNA damage and photo-immunosuppression; are also described. DNA repair systems, photo-reactivation, and photolysis, the effectiveness of sunscreens, suntan, and solaria are also detailed.

Strategies to protect against excessive exposure to ultraviolet (UV) radiation are required to reduce the risk of melanoma, non-melanoma skin cancers, and eye diseases. The programs that have been most effective in reducing sun exposure involve combinations of education intended to change individual beliefs and behavior, tools for personal protection from the sun, and the creation of environments that support sun protection. Specific strategies include community-wide media campaigns, school-based interventions, counseling by healthcare providers about sun protection, education on the appropriate use of protective clothing and sunscreen, and policies to restrict access to indoor tanning beds. Sun protection strategies are most effective when introduced in childhood, although interventions in adulthood can also reduce skin cancer incidence. There are health risks of complete sun avoidance, so a balance between inadequate and excessive sun protection is necessary.

Appropriate evaluation of an eyelid lesion is necessary before deciding on a course of surgical or nonsurgical treatment. A differential diagnosis is established based on the patient’s history and the physical characteristics of the mass. Many eyelid masses have similar physical and behavioral characteristics. In some cases, radiologic examination can be helpful in determining the extent or even the type of tumor. Certain malignant tumors may look benign or have the appearance of other malignancies. Biopsy is required for the definitive diagnosis. When faced with an eyelid lesion, the physician must first determine whether the lesion is benign or malignant. This determination will then dictate the next direction of diagnostic tests. If a mass has been present for several months to years or if there has been a history of bleeding, malignancy must be considered. Pain is usually not a component of malignancy, but some moderate discomfort may be present. Malignant lesions are usually destructive. The skin may be altered by a mass or ulceration. A malignancy located at the eyelid margin usually results in loss of lashes. Small malignancies may be similar in appearance to early inflammations, but as these malignancies grow, destruction of tissue is usually evident. If malignancy is not suspected, then a decision as to whether the lesion is inflammatory or not should be made. Small inflammatory lesions such as blepharitis may be ulcerative, cause loss of lashes, and simulate eyelid carcinoma. Swelling, redness, and pain are all characteristics of inflammatory masses such as styes or chalazia. Infected glands away from the lid margin can also have these signs. Swelling in the area of the medial canthus could be a lacrimal sac mucocele if there is no evidence of redness, or it could be a lacrimal sac tumor. Benign lesions that are not inflammatory may have swelling but usually not pain. They may be translucent, such as hair follicle cysts. These tumors often transilluminate. They may have a clear fluid that can be easily identified through thin skin, or there may be a yellowish content such as sebaceous material within the cyst. Some benign lesions may be papillomatous or have keratinized ends, such as cutaneous horns.

Examination of the face and hands can identify significant skin diseases and also provide clues to the presence of underlying systemic disease. Many patients ignore even malignant skin tumours because they are often painless, subtle in appearance, and may be slow-growing. Dental healthcare professionals should be aware of how to recognize malig­nant skin tumours. If suspicious, but unsure of the nature of the lesion, the patient should be referred to their general medical practitioner for further evaluation. If malignancy is obvious, then an urgent referral to an appropriate specialist (dermatologist, plastic surgeon, or oral and max­illofacial surgeon) should be made using the ‘2-week wait’ (2WW) path­way (Chapter 1). Benign lesions and inflammatory diseases are more common and are important considerations in the differential diagnosis of head and neck skin abnormalities. It is important that the dental healthcare professional should be able to recognize common skin infections involving the oro-facial region. Some infections, such as erysipelas, can mimic cellulitis associated with a dental infection. When infection is diagnosed, it is vital to consider the underlying or predisposing factors, as these may be not only important diagnoses, but also may require treatment to achieve an effective clin­ical outcome. The adage ‘infection is the disease of the diseased’ is a useful reminder when dealing with patients presenting with infection. Direct inoculation of Streptococcus into skin through minor trauma is the most common initiating factor for erysipelas, which occurs in iso­lated cases. Infection involves the upper dermis and, characteristically, spreads to involve the dermal lymphatic vessels. Clinically, the disease starts as a red patch that extends to become a fiery red, tense, and indurated plaque. Erysipelas can be distinguished from cellulitis by its advancing, sharply defined borders and skin streaking due to lymphatic involvement. The infection is most common in children and the elderly, and whilst classically a disease affecting the face, in recent years it has more frequently involved the leg skin of elderly patients. Although a clinical diagnosis can be made without laboratory testing, and treat­ment is antibiotic therapy, when the diagnosis is suspected in dental practice, referral to a medical practitioner is recommended.

The author’s heart attack in his early 40s, when working as a rural general practitioner (GP) in the National Health Service (NHS). The author’s career journey: from his medical school training, working as a rural GP for the NHS, his transition to specialist training, and work as an occupational physician. The experience of doctors as patients: first from the author’s personal perspective, but also the tricky matter of treating a fellow doctor. The implications of doctors as patients. The problem of middle-aged men as patients: poor health-seeking behaviour and poor compliance. Sudden death in a patient. The author’s new focus on health and prevention, not disease and treatment. Paternalism in the doctor–patient relationship. Patients or clients? The autocratic doctor, and the concept of patient-centred care. What do patients want from their doctors? The concept of working in partnership with patients.

Skin cancer is one of the few types of cancer for which exposure to the major carcinogen, solar ultraviolet (UV) radiation, is strongly implicated on the basis of descriptive epidemiologic data alone. There are three major forms of skin cancer considered in this chapter—melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC)—and each appears to have different causal relations to the pattern and total amount of sun exposure. High-intensity UV exposure and long-term UV exposure appear to be involved differentially in the various skin cancers and their subtypes. Underlying molecular mechanisms are becoming better understood, though many aspects like the cells of origin and the exact roles of intermediate lesions like actinic keratoses and nevi remain unclear. Because exposure of skin to UV radiation is modifiable, skin cancers are substantially preventable.

Ultraviolet (UV) radiation is the principal cause of over 95% of keratinocyte cancers (basal cell carcinomas and squamous cell carcinomas of the skin), the most common cancers in white populations worldwide. UV radiation also causes an estimated 60%–90% of cutaneous melanoma, the cancer affecting the skin’s pigment-producing cells. In addition, UV radiation is the major cause of many eye diseases, including ocular cancers and cataract, the commonest cause of blindness, and is responsible for the underlying changes in skin aging, on which billions of dollars are spent annually in efforts to repair the damage. The sun is the principal source of human exposure to UV radiation. However, artificial sources are encountered in a wide range of industrial and medical settings, and increasingly from commercial tanning facilities. By the late twentieth century, nearly epidemic increases in skin cancer incidence had occurred in white populations, especially in Australia and New Zealand.

Melanoma is a cancer of melanocytes, cells that produce the brown-black skin pigment melanin. Melanocytes originate in cells of the neural crest and migrate during embryogenesis, principally to the epidermis, eyes, and some mucous membranes (mouth, nose, esophagus, anus, genitourinary organs, and conjunctiva). Cutaneous melanoma afflicts mainly fair-skinned people of European origin, among whom sun exposure is the major cause. Five-year relative survival can exceed 90%. Invasive cutaneous melanoma in US whites occurs mostly on the trunk (34%), and upper limbs and shoulders (26%). Melanoma incidence rates have been increasing predominantly in European-origin populations. Ultraviolet (UV) radiation, from the sun or artificial tanning devices, probably both initiates and promotes melanoma. Nevi are markers of increased melanoma risk and direct precursors in some cases; nevus-prone people may require only modest sun exposure to initiate melanoma. Other risk factors include family history and sun sensitivity.

There are a number of important preventable risk factors that have been associated with the prevalence and incidence of various types of cancers. These risk factors include sedentary lifestyle, poor diet, obesity, sun exposure, and tobacco use (Friedenreich & Orenstein, 2002; Healthy People 2010, 1998; Pappo, 2003; Slattery, Schumacher, West, Robison, & French, 1990). These risk factors are modifiable, and early prevention in childhood may reduce the likelihood of developing cancers such as melanoma and lung, colon, breast, prostate, and endometrial cancers (IARC Working Group, 2002). For example, according to the International Agency for Research on Cancer, between one fourth and one third of cancer cases may be attributed to the combined effects of obesity and physical inactivity (IARC Working Group, 2002), thus promoting both weight control and physical activity in youths may be beneficial for preventing cancer. Therefore, the identification of multiple risk factors that may be linked to cancer prevention that could be incorporated into prevention programs may be an effective approach for cancer prevention in youth. A social ecological model is presented in this chapter as a framework for understanding multilevel strategies for promoting healthy lifestyles to prevent cancer in youths (Bronfenbrenner, 1979, 1992; Wilson & Evans, 2003). According to the ecological model, health behavior is affected by intrapersonal, social, cultural, and physical environmental variables. A social ecological framework (McLeroy, Bibeau, Steckler, & Glanz, 1988) conceptualizes health behavior (e.g., physical activity) as affected by multiple levels of influence. Based on this social ecological model, five levels of influence are specified: (a) individual influences (e.g., biological and psychosocial); (b) interpersonal influences (e.g., family, peers); (c) institutional factors (e.g., school, work sites); (d) community factors (e.g., relationship among organizations, institutions, and social networks); and (e) public policy (e.g., laws and policies at the local, state, national, and international levels). In this model, health behaviors such as physical activity, nutrition, sun exposure, and tobacco use are conceptualized as a function of the interaction of individual, family, and peer influences and school, community, mass media, and public policy influences.

The clinical applications of diagnostic ultrasound in ophthalmology were initiated by G.H. Mundt and w.F. Hughes ( 1 ) (1956) as well as A. Oksala and A. Lehtinen ( 2 ) (1957) introducing A-scan, and by G. Baum ( 3 ) (1958) introducing and pioneering B-scan. The first medical society for diagnostic ultrasound was founded in 1964 (Societas Internationalis de Diagnostica Ultrasonica in Ophthalmologia) with subsequent biennial congresses. Ophthalmic diagnostic ultrasound is the only ultrasonographic method heavily relying on A-scans besides the B-scans. Today, four distinct echographic methods (utilizing different types of instrumentation) are being used in ophthalmology: 1) Biometric A-scans for measuring the axial eye length. 2) Low-frequency B-scans for the examination of the posterior eye segment and the anterior orbit utilizing 10–20MHz. 3) High-frequency B-scans for the evaluation of the anterior eye segment applying 25–50MHz. 4) Standardized Echography , a combination of diagnostic as well as biometric A-scan (8MHz) and B-scan echography (10–50MHz) for a comprehensive ultrasonographic examination of the eye (anterior and posterior segments) and of the entire orbit and periorbital region. A-scan (8–12MHz) is used for measurements of the axial eye length, today an important contribution to the calculation of intraocular lens power in cataract surgery. F. Jansson ( 4 ) (1963) proposed biometric A-scan as an immersion (non-touch) technique and also measured the involved sound velocities of the anterior chamber, the lens, and the vitreous cavity which since then have been the accepted standard values. At first, axial eye length measurements were mostly used in studies regarding glaucoma and myopia. when, in the early 1970s, the implantation of artificial lenses during cataract surgery spread quickly, the much more precise but more time-consuming and demanding immersion method temporarily gave way to an easier and quicker contact method. Lately, however, advances in cataract surgery, especially the use of multifocal lenses as well as the competition from laser technology, resulted in a return of Jansson’s immersion method.

The term ‘oral cancer’ encompasses all malignant neoplasms affecting the oral cavity. The majority, greater than 90%, are squamous cell car¬cinomas. The remainder are uncommon and comprise minor salivary gland adenocarcinomas, malignant melanoma, sarcomas, haemato-logical malignancies, and metastases to the oral cavity from cancers at other sites. Oral squamous cell carcinoma is a malignant epithelial neoplasm that arises from the lining mucosa of the oral cavity. The tumour shows vary¬ing degrees of squamous differentiation and is characterized by invasion of local structures and metastasis to regional lymph nodes, followed by metastasis to other organ systems (e.g. lungs and bones) later in the course of the disease. Epidemiological data pertaining to oral cancer can be difficult to evalu¬ate because of variations in the methods of data collection (Box 3.1). Notwithstanding these confounding variables, a database produced by the International Agency for Research on Cancer (GLOBOCAN), esti-mated there were over 400,000 new cases of lip, oral, and pharyngeal cancer worldwide in 2012, placing the disease in ninth position with breast, prostate, lung, colorectal, cervical, stomach, liver, and uterine cancer being more common. These data suggest that oral cancer is uncommon, but there are enormous variations worldwide. Whereas oral cancer is relatively uncommon in the UK, accounting for 2% of all cancers, in India and parts of South-East Asia it is the most common malignant neoplasm and accounts for around a third of all cancers. Furthermore, the incidence rates for large countries, such as India and the USA, conceal regional and ethnic variations. For example, incidence rates tend to be higher in urban as opposed to rural communities, and in the USA are higher for blacks than whites. In the United Kingdom, inci¬dence rates are slightly higher in Scotland than in England and Wales. In the United Kingdom the incidence of oral cancer is 9 per 100,000 of the population, which represents around 6,800 new cases per annum. The disease is more common in men than in women; the male:female ratio is currently 2:1. Oral cancer incidence increases with age, and the majority of cases (greater than two-thirds) are diagnosed after the age of 50 years old; less than 5% occur in individuals below the age of 40 years old.

The differential diagnosis of rhegmatogenous retinal detachment includes secondary (nonrhegmatogenous) retinal detachment and other entities that may simulate a retinal detachment. Nonrhegmatogenous detachments are categorized as exudative (serous) and tractional detachments. Conditions that may be mistaken for retinal detachment include retinoschisis, choroidal detachment or tumors, and vitreous membranes. Sometimes benign findings in the peripheral retina are mistaken for retinal breaks. The most prominent feature of the fundus is the optic nerve head or disc, the only place in the human body that affords a direct view of a tract of the central nervous system. The foveola, the functional center of the fundus, is located in the center of the fovea, which has a diameter of about 5°. The macula is centered on the fovea and has a diameter of about 17°. The multiple branches of the central retinal artery are readily identifi ed by their bright red color and relatively narrow caliber. The multiple tributaries of the central retinal vein are recognized by their dark red color and relatively wider caliber. In a darkly pigmented fundus, the choroidal vessels in the posterior pole can be obscured from view, but in an eye with minimal pigment, they are readily visible. The venous tributaries of the choroid that make up the vortex veins are usually easily seen. The most prominent features of the choroidal venous system are the vortex ampullae, of which there are usually four (but sometimes more). They are located approximately in the 1-, 5-, 7-, and 11-o’clock meridians, just posterior to the equator. The horizontal meridians are usually identifiable by their radially oriented, long posterior ciliary nerves, and infrequently the long posterior ciliary artery can be seen adjacent to the nerve. The nerve is relatively broad and has a yellow color, and the artery is identifiable by its red color. The artery is usually inferior to the nerve temporally, and superior to it nasally (Figure 5–1).

Epithelial malignancy of the eyelid is a common problem, representing about 14% of skin cancers in the head and neck region. The goals when treating any skin cancer are complete elimination of the tumor and minimal sacrifice of normal adjacent tissues. These concepts are of paramount importance when treating periocular epithelial malignancies because of the complex nature of the periocular tissues and their critical function in protecting the underlying globe, as well as the increased risk that recurrent tumor in this area poses. Many modalities have been advocated, by a variety of medical practitioners, for the treatment of epithelial malignancies in the periocular region. There are two key considerations in selecting a treatment for skin cancers. The first is that the selected modality must be capable of eradicating all tumor cells to which it is applied. The second is that some mechanism must exist to ensure that it is applied to all the existing tumor cells. Because tumors of the lid margins and canthi often exhibit slender strands and shoots of cancer cells that may infiltrate beyond the clinically apparent borders of the neoplasm, appropriate monitoring to ensure that the treatment modality reaches all of the cancer cells is essential. Numerous studies have demonstrated that clinical judgment of tumor margins is inadequate, significantly underestimating the area of microscopic tumor involvement. The introduction of frozen-section control to document adequacy of tumor excision marked a major advancement in the treatment of eyelid malignancies and now represents the standard of care. Any treatment modality that does not use microscopic monitoring of tumor margins must instead encompass a wider area of adjacent normal tissue in hopes that any microscopic extensions of tumor will fall within this area. The purpose of this chapter is to explore alternative methods of periocular cancer treatment. Mohs micrographic technique is a refinement of frozen-section control of tumor borders that, by mapping tumor planes, allows a three-dimensional evaluation of tumor margins rather than the two-dimensional examination provided by routine frozen section. The modality was initiated by Frederick E. Mohs, MD, in 1936.

Questions

A tumour in which of the following areas is most likely to lead to behavioural/psychiatric manifestation?

Frontal lobe

Temporal lobe

Posterior fossa

Parietal lobe

Occipital lobe

Which of the following is least associated with a frontal lobe tumour?

Decline in IQ

Dysexecutive...

The anatomy of the orbital vascular bed is complex, with tremendous individual variation. The main arterial supply to the orbit is from the ophthalmic artery, a branch of the internal carotid artery. The external carotid artery normally contributes only to a small extent. However, there are a number of orbital branches of the ophthalmic artery that anastomose with adjacent branches from the external carotid artery, creating important anastomotic communications between the internal and external carotid arterial systems. The venous drainage of the orbit occurs mainly via two ophthalmic veins (superior and inferior) that extend to the cavernous sinus, but there are also connections with the pterygoid plexus of veins, as well as some more anteriorly through the angular vein and the infraorbital vein to the facial vein. A working knowledge of the orbital vasculature and lymphatic systems is important during orbital, extraocular, or ocular surgery. Knowing the anatomy of the blood supply helps one avoid injury to the arteries and veins during operative procedures within the orbit or the eyelid. Inadvertent injury to the vasculature not only distorts the anatomy and disrupts a landmark but also prolongs the surgery and might compromise blood flow to an important orbital or ocular structure. Upon entering the cranium, the internal carotid artery passes through the petrous portion of the temporal bone in the carotid canal and enters the cavernous sinus and middle cranial fossa through the superior part of the forame lacerum . It proceeds forward in the cavernous sinus with the abducens nerve along its side. There it is surrounded by sympathetic nerve fibers (the carotid plexus ) derived from the superior cervical ganglion. It then makes an upward S-shaped turn to form the carotid siphon , passing just medial to the oculomotor, trochlear, and ophthalmic nerves (V1). After turning superiorly in the anterior cavernous sinus, the carotid artery perforates the dura at the medial aspect of the anterior clinoid process and turns posteriorly, inferior to the optic nerve.

Questions

52-year-old man presents to the clinic for review some six weeks after starting phenytoin for complex partial seizures. He is very concerned as he has a rash which began on his face but quickly spread over the upper body. It begins as large,...