Christine J. Ko - Dermatopathology

Edition History John Wiley & Sons, Ltd (3e, 2017, 2e 2011); Christine J. Ko and Ronald J. Barr (1e, 2008)

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Library of Congress Cataloging‐in‐Publication Data

Names: Ko, Christine J., author. | Barr, Ronald J. (Dermatopathologist) author.

Title: Dermatopathology : diagnosis by first impression / Christine J. Ko, Ronald J. Barr.

Description: Fourth edition. | Hoboken, NJ : Wiley‐Blackwell, 2022. | Includes index.

Identifiers: LCCN 2021049387 (print) | LCCN 2021049388 (ebook) | ISBN 9781119826057 (paperback) | ISBN 9781119826064 (adobe pdf) | ISBN 9781119826071 (epub)

Subjects: MESH: Skin Diseases–diagnosis | Skin Diseases–pathology | Microscopy | Skin–pathology | Atlas

Classification: LCC RL96 (print) | LCC RL96 (ebook) | NLM WR 17 | DDC 616.5/075–dc23/eng/20211015

LC record available at https://lccn.loc.gov/2021049387LC ebook record available at https://lccn.loc.gov/2021049388

Cover Design: Wiley

Cover Images: Courtesy of Christine J. Ko

Main image shown is epidermodysplasia verruciformis; small images, from left to right, are subcutaneous fat necrosis of the newborn, mastocytosis, tubular apocrine adenoma, and plantar fibromatosis.

To Ulla, Anna, Jessica, and Sara who let me pursue

my career while they took care of everything else.

– Ronald J. Barr

To Peter, Dylan, and Owen.

– Christine J. Ko

The purpose of this book is to focus on a selection of commonly tested entities, showing low‐power to high‐power views. Major differences among diagnoses that are sometimes confused are emphasized on “Key Differences” pages to help train the eye to rapidly notice distinctive features. As a picture is worth a thousand words, text is kept to a minimum. This book should be used as a companion to dermatopathology textbooks and as a pictorial reference/study tool, given that this approach is utilized by the experienced dermatopathologist when constructing examination questions. Major distractors are based on gestalt rather than etiology or conventional classifications; lookalikes that are the most deceptive often have no obvious relationship to the correct diagnosis. This book will also be helpful to the dermatopathology novice as it introduces a simple and effective way to approach a slide and, to that end, common diagnoses have been specifically included (i.e., actinic keratosis, basal cell carcinoma).

Dr James H. Graham, MD, master of dermatopathology and dermatology, who taught me most of what I know. (Ronald J. Barr)

Dr Ronald Barr, Dr Scott Binder, my dermatopathology colleagues at Yale (Dr Jennifer McNiff, Dr Earl Glusac, Dr Shawn Cowper, Dr Anjela Galan, Dr Marcus Bosenberg, Dr Peggy Myung, Dr Gauri Panse, Dr William Damsky, and Dr Antonio Subtil Deoliveira [still part of my Yale dermatopathology family]), Dr Jean Bolognia – their insights over the years have been invaluable. We also acknowledge the residents at Yale, those in Thailand, and Hadas Skupsky, who rotated with Dr Barr, all of whom gave constructive feedback on how to improve the atlas. Thanks is also due to the team at Wiley‐Blackwell for all their efforts to improve the book. (Christine J. Ko)

This book is accompanied by a companion website:

www.wiley.com/go/ko/dermatopathology4e

The website includes:

Interactive multiple choice questions

PowerPoints of all figures from the book for downloading

Recognizing a disease process on a histopathologic slide becomes instantaneous, with increasing familiarity. Breaking this process down into the “how” is difficult, especially given that the steps may not be the same for each individual. Nonetheless, on a basic level, it is important to separate a solitary growth (“tumor” or “lesion”) from a rash (“inflammatory” process; Figures 1–3), focus on the most obvious pathologic finding, and run through a differential diagnosis. With experience, that “obvious” pathologic finding (i.e., where to start) becomes second nature. The diseases in this atlas are grouped, arbitrarily, by such findings (see the Index by Pattern). Notably, basic algorithms are ultimately overly simplistic, and there is overlap of the two major divisions in Figure 1(tumor versus rash). For example, clear cell acanthoma can architecturally mimic psoriasis, mycosis fungoides can appear to be a dermatitis, and epithelioid sarcoma can be confused with a palisading granulomatous process.