The impact of GP sub-specialisation and dermatoscopy use on diagnostic accuracy for melanomas in Australia

Transcription

1 The impact of GP sub-specialisation and dermatoscopy use on diagnostic accuracy for melanomas in Australia Cliff Rosendahl, Gail Williams, Diann Eley, Tobias Wilson, Greg Canning, Jeffrey Keir, Ian McColl, David Wilkinson. J Am Acad Dermatol /j.jaad

2 How good are we at finding melanomas?

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8 Does it matter?

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12 Photograph by Alan Cameron

13 NNT Number Needed to Treat for each melanoma diagnosed Number of lesions treated for each melanoma diagnosed Measure of specificity (not sensitivity) Diverse methods of calculation

14 NNT previous studies Naevi + Melanomas/Melanomas ( ) Naevi + Melanomas + Seb K/Melanomas (19-30) All lesions EXCISED/Melanomas (39) All predicted Melanomas/Melanomas (4)

15 Previous NNT studies numbers of melanomas

16 Previous NNT studies NNT values

17 Skin Cancer Audit Research Database

18 Doctor type Dedicated skin cancer practitioner (DSCP) GP with a special interest in skin cancer (GPSISC) General practitioner (GP)

19 Dermatoscopy use High all pigmented skin lesions Medium most days Low/none less than weekly/not at all

20 NNT Lesions tested to exclude melanoma / melanomas Prior declaration of intent!

21 RESULTS

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23 Lesions tested to exclude melanoma (51) (86) (56)

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25 (95% CI P <0.0001) ( ) ( ) ( ) Doctor-type

26 (95% CI P <0.0001) ( ) ( ) ( ) Dermatoscopy-use

27 The association between NNT and doctor type remained (P< ) when adjusted for dermatoscopy use and other variables. The association between NNT and dermatoscopy use disappeared (P = 0.41) when adjusted for practice type and other variables (doctor-type and dermatoscopy use were too inter-dependant)

28 Fact General practitioners sub-specialized in skin cancer treatment had a higher use of dermatoscopy and excised half the number of benign lesions for each melanoma detected compared to their generalist colleagues Opinion The role of such sub-specialized general practitioners should be defined and the factors that make their performance more effective including trained dermatoscopy use should be promoted

29 For the first time it is shown that there is a measureable benefit of sub-specialisation in General Practice

30 Skin Thank you! Cancer Audit Research Database

31 Dermatoscopy in Routine Practice Chaos & Clues Presented by Dr Cliff Rosendahl & Dr Alan Cameron

32 (1920) Dermatology Dermatologists Dermatoscope Dermatoscopy

33 Conflict of interest a method which cannot be taught is barely a method at all.

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35 ALL pigmented lesions Detects malignancy ANY type No need to decide whether melanocytic Can be applied at examination speed Efficacy similar to the other algorithms

36 What is dermatoscopy? a non-invasive diagnostic technique for skin lesions a low powered microscope designed for visualisation of pigmentation and vessels by reducing the amount of light reflected off the skin surface by either Contact fluid immersion polarising filters

37 Clinical examination looks at lesions in the horizontal plane In contrast, conventional microscopy looks at lesions in the vertical plane

38 Because melanin appears as different colours at different depths in the skin dermatoscopy provides information in both the horizontal and vertical planes. It provides a 3-dimensional view Atlas of Dermoscopy Marghoob Braun Kopf. Page 11

39 What do you put your dermatoscope on? Every lesion? Selected lesions which break the pattern?

40 Photograph Cliff Rosendahl

41 Photograph Cliff Rosendahl

42 Photograph Cliff Rosendahl

43 Photograph Cliff Rosendahl

44 Do you need dermatoscopy? Photograph Cliff Rosendahl

45 Photograph Cliff Rosendahl

46 Photograph Cliff Rosendahl

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48 Instruments and flight charts

49 Algorithms 1987 Pehamberger Classic Pattern Analysis 1989 First hand-held dermatoscope consensus meeting metaphoric terminology 1994 Stolz ABCD rule 1996 Menzies method 1998 Argenziano 7 point checklist 2000 Soyer/Argenziano 3 point checklist 2007 CASH (color, architecture, symmetry, and homogeneity) version of pattern Analysis

50 Algorithms 1987 Pehamberger Classic Pattern Analysis 1989 First hand-held dermatoscope consensus meeting metaphoric terminology 1994 Stolz ABCD rule 1996 Menzies method 1998 Argenziano 7 point checklist 2000 Soyer/Argenziano 3 point checklist 2007 CASH (color, architecture, symmetry, and homogeneity) version of pattern Analysis

51 Do you use Pattern Recognition?

52 In the next slide I will present 2 images One will be innocent and one suspicious I want you to see how long it takes to decide

53 Pattern recognition is innate human behaviour Photographs Cliff Rosendahl

54 In contrast to pattern recognition Pattern analysis is the process of describing and analysing the objects in a logical fashion so they can be defined in a repeatable and teachable manner

55 Algorithms 1987 Pehamberger Classic Pattern Analysis 1989 First hand-held dermatoscope consensus meeting metaphoric terminology 1994 Stolz ABCD rule 1996 Menzies method 1998 Argenziano 7 point checklist 2000 Soyer/Argenziano 3 point checklist 2007 CASH (color, architecture, symmetry, and homogeneity) version of pattern Analysis

56 Melanocytic Criteria Network Pseudo network Aggregated brown globules Pseudopods/radial streaming Parallel ridge pattern (acral) Homogenous blue pigmentation

57 Ink spot lentigo Pigmented solar keratosis Solar lentigo/piec Solar lentigo Network occurs in many non-melanocytic lesions

58 Photographs Cliff Rosendahl Pseudonetwork occurs in facial solar lentigines and facial solar keratoses

59 Photograph Cliff Rosendahl Aggregated brown globules occur in BCCs Parallel ridge pattern (acral) occurs in corneal haemorrhage Homogenous blue pigmentation occurs in tattoos

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61 Melanocytic Criteria You need a microscope to see melanocytes!

62 Why a new method??

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64 There is no doubt that the method will have to be improved. There is also no doubt that methods will have to be found to make pattern analysis more objective Pehamberger H, Binder M, Steiner A, Wolff K. In vivo epiluminescence microscopy: improvement of early diagnosis of melanoma. J. Invest. Dermatol. 1993;100(3):356S- 362S.

65 What makes Pattern Analysis difficult? Lack of clear definitions Descriptions that depend on diagnosis Inconsistent metaphorical terminology No clear diagnostic pathway

66 Photograph Alan Cameron

67 2007 Revised pattern Analysis Harald Kittler

68 Revised Pattern Analysis Rebuilds from the firm foundation of Classic pattern Analysis (no subsequent system gave better results) Iconoclastic - Poorly defined confusing metaphorical language replaced by clearly defined geometric terminology No need to decide melanocytic status as a (hazardous) first step

69 Towards a more objective Pattern Analysis Descriptions precede diagnosis clear and objectively defined descriptions are the same regardless of diagnosis no metaphoric descriptions A clear structure to reach a diagnosis

70 Pattern + Colours + Clues = Diagnosis DESCRIPTION PRECEDES DIAGNOSIS! Describing a lesion assists the cognitive process. Metaphoric terms with preconceived diagnostic implications are not used.

71 Pattern Analysis There are only 5 basic elements.

72 Lines Reticular Pseudopods Branched Circles parallel Clods Radial Dots Curved

73 Definitions Line : a two-dimensional continuous object with length greatly exceeding width Pseudopod : a line with a bulbous end Circle : a curved line equidistant from a central point Clod : any well circumscribed, solid object larger than a dot. Clods may take any shape Dot : an object too small to have a discernable shape Structureless : An area with no basic structure predominating

74 Pattern There are only 5 basic elements. A pattern consists of multiple repetitions of basic elements.

75 Line a two-dimensional continuous object with length greatly exceeding width. Acral naevus Photograph Alan Cameron

76 Photograph Alan Cameron

77 Courtesy Stelios Minas

78 Photograph Alan Cameron

79 Pseudopod a line with a bulbous end. Reed naevus Photograph Alan Cameron

80 Photograph Alan Cameron Circle a curved line equidistant from a central point. Melanoma in situ face

81 Photograph Alan Cameron Dot an object too small to have a discernable shape. Melanoma courtesy Ian McColl

82 Clod any well circumscribed, solid object larger than a dot. Clods may take any shape. Invasive melanoma Photograph Alan Cameron

83 Photographs Alan Cameron

84 Structureless an area without basic elements, or where no basic element predominates. Photograph Alan Cameron

85 Pattern + Colours + Clues = Diagnosis

86 Black Melanin in Stratum corneum, congealed blood Melanin Dark brown Light brown Melanin in the epidermis, dense Melanin in the epidermis, delicate Grey Melanin in the papillary dermis Blue Melanin in the reticular dermis Keratin Orange Yellow Combination of melanin and keratin, serum crust Keratin White Absence of melanin, sclerosis of the dermis, keratin Haemoglobin Red Purple Blood Blood (poorly oxygenized)

87 Pattern + Colours + Clues = Diagnosis

88 Pattern + Colours + Clues = Diagnosis Clues to a specific diagnosis Clues to malignancy ( Chaos and Clues )

89 CLUES TO MALIGNANCY (Chaos and Clues)

90 each person should develop their own method modified by Jeff Keir

91 Polygons Photographs Cliff Rosendahl

92 Evaluating Chaos & Clues Photograph Cliff Rosendahl

93 Tested on 463 consecutive pigmented lesions in an Australian general practice

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95 CONCLUSIONS A simplified algorithm based on pattern analysis (CHAOS & CLUES) is a useful tool for all types of pigmented lesions, including those which are non-melanocytic Sensitivity % Specificity %

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97 Asymmetry of structure or colour

98 Chaos No chaos Judge on pattern and colour, not on outline

99 Photograph Alan Cameron

100 Photograph Alan Cameron concentric = no chaos Be suspicious of other combinations of more than one pattern or colour

101 Photograph Alan Cameron

102 Photograph Alan Cameron

103 CHAOS In a Blink! SCAN for CHAOS The presence or absence of CHAOS can usually be assessed at the speed of a blink! With practice it is a scanning assessment If in doubt assume chaos and assess for clues

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105 In contrast to scanning for CHAOS the search for CLUES involves thoughtful examination

106 1. Eccentric structureless area

107 Eccentric Structureless Area Any colour except skin colour If white usually represents regression Often scattered grey/blue dots Red- increased blood flow Coloured- dense chaotic melanin deposition

108 Photograph Cliff Rosendahl

109 Photographs Cliff Rosendahl

110 Photograph Alan Cameron

111 Photograph Cliff Rosendahl

112 2. Thick lines reticular or branched

113 Thick Lines Reticular or Branched in benign lesions, the lines are thinner than the holes they enclose Lines thicker than the holes they enclose are seen in melanoma melanomas usually display variability of line thickness

114 Photographs Cliff Rosendahl

115 Photograph Alan Cameron

116 Photographs Alan Cameron

117 3. Grey or blue structures

118 Grey or Blue Structures Lines, circles, clods or dots Represent melanin in the dermis Melanoma cells or melanophages or free melanin

119 Photographs Cliff Rosendahl

120 Photographs Cliff Rosendahl

121 Photographs Cliff Rosendahl Dermatomicrographs Richard Williamson Rosendahl C, Cameron A, Bulinska A, Williamson R, Kittler H. Dermatoscopy of a minute melanoma. Australas. J. Dermatol Feb;52(1):76 8.

122 Photograph Cliff Rosendahl

123 4. Black dots or clods, peripheral

124 Black Dots or Clods, Peripheral Black dots and clods can occur centrally in naevi. They can occur anywhere in a melanoma, so peripheral black dots and/or clods are a clue to malignancy.

125 Photograph Alan Cameron Photograph Alan Cameron

126 Photograph Alan Cameron

127 Photographs Alan Cameron

128 Photographs Cliff Rosendahl

129 5. Lines radial or pseudopods, segmental

130 Lines Radial or Pseudopods, Segmental Melanocytic lesions: Represent radial proliferation of nests of melanocytes Only requires one pseudopod or 1 radial line Basal cell carcinomas: Radial lines converging

131 Photographs Cliff Rosendahl

132 Photographs Cliff Rosendahl

133 Lines radial segmental also a clue to piec Photographs Cliff Rosendahl

134 6. White lines

135 White Lines the colour white is the exception to the rule that structures are defined by pigment. lines are white when they are lighter than surrounding skin Skin coloured lines are occasionally a weak clue- not to be ignored

136 Photograph Alan Cameron

137 Photograph Peter Bourne

138 Photograph Alan Cameron

139 Photograph Alan Cameron

140 Photographs Alan Cameron

141 Nodular melanomas may be symmetrical Photographs Cliff Rosendahl

142 7. Polymorphous vessels

143 Polymorphous Vessels A relatively weak clue (pigment structures should take priority when present) More than one vessel pattern Dot vessels often seen in melanomas

144 Vessel patterns Vessel structure left: A- dots; B- clods; C- lines; D- looped; E- curved; F- serpentine; G- helical; H- coiled Vessel arrangement right: A- random; B- clustered; C- serpiginous, D- linear; E- centred; F- radial; G -reticular; H- branched

145 Photograph Cliff Rosendahl

146 Looped Serpentine Helical Photograph Cliff Rosendahl

147 Photographs Cliff Rosendahl

148 Photograph Cliff Rosendahl

149 Photographs Cliff Rosendahl

150 Photograph Cliff Rosendahl

151 8. Lines parallel, ridges (acral) or chaotic (nails)

152 Lines parallel, ridges (acral) or chaotic (nails) Acral skin has a pattern of pattern of ridges and furrows Pigmentation tends to follow either the ridges or the furrows, creating parallel lines In naevi, pigment follows the furrows

153 Photograph Alan Cameron

154 Photograph Alan Cameron Photograph Alan Cameron

155 Lines parallel, ridges (acral) or chaotic (nails) Acral skin has a pattern of pattern of ridges and furrows Pigmentation tends to follow these ridges and furrows Pigmentation on the ridges is a clue to melanoma even in a symmetrical lesion

156 courtesy Jean-Yves Gourhant

157 Photographs Alan Cameron

158 Photographs Alan Cameron

159 Lines parallel, ridges (acral) or chaotic (nails) Lines parallel on nails, varying in width interval and colour

160 Photograph Cliff Rosendahl

161 Photograph Cliff Rosendahl

162 Photograph Cliff Rosendahl

163 1 Poster 1 smart kid + = 1 rare in-situ melanoma

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165 Excluding seborrhoeic keratoses

166 Photograph Alan Cameron

167 Photograph Alan Cameron

168 Excluding seborrhoeic keratoses Multiple orange or yellow clods Multiple white clods Thick curved or reticular lines Well demarcated border Vessels as loops Multiple grouped similar lesions Malignant conditions can have individual criteria Weigh the clues to arrive at a diagnosis If in doubt at all - BIOPSY

169 Photograph Alan Cameron

170 Photograph Alan Cameron

171 Photograph Alan Cameron

172 Photograph Alan Cameron

173 Photograph Alan Cameron

174 Photographs Alan Cameron

175 Photographs Alan Cameron

176 Photograph Alan Cameron

177 The Aoraki Principle If with respect to any skin lesion you remain unable to make a CONFIDENT SPECIFIC BENIGN Diagnosis BIOPSY IS INDICATED Photograph Cliff Rosendahl

178 Photographs Cliff Rosendahl

179 Photograph Cliff Rosendahl Level 1 melanoma No clues to malignancy but he was not aware how long it had been there

180 Chaos and Clues in everyday practice

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187 Exceptions

188 Photographs Alan Cameron

189 Photograph Alan Cameron

190 The most valuable clinical sign of all

191 The break in the pattern The almost inaudible snap of a twig

192 Photographs Cliff Rosendahl Photograph Cliff Rosendahl

193 Photograph Cliff Rosendahl

194 Photograph Cliff Rosendahl

195 Photograph Cliff Rosendahl

196 The signature of an assassin Melanoma writes its message on the skin with its own ink and it is there for all to see Dr Neville Davis Modern concepts of melanoma and its management Annals of Plastic Surgery 1978:1:

197 Look for the break in the pattern Scan for chaos Examine for clues

198 Take out the assassin

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200 If there is more than one way to skin a cat why not choose the easiest method? Harald Kittler

201 If there is more than one way to skin a cat why not choose the easiest method? Harald Kittler Thank you!