細胞病理のエキスパートを目指す人へ

同窓会雑誌６号に掲載される記事の依頼を受けました。紹介いたします。 2011年3月和歌山県立医科大学を辞して、神戸常盤大学保健科学部医療検査学科教授に転身いたしました。今まで和歌山県立医科大学第2病理学（人体病理学）教室で行ってきた細胞検査士養成（20年間で14名が資格認定）を、大学教育として行うことを目的に、神戸常盤大学に現職教授として移動しました。早いものでまる2年となります。細胞検査士養成コースの担当者として、臨床検査技師の育成と細胞検査士の養成を担当しています。4年制大学の医療検査学科で、4回生の1年間を卒業研究と並行し細胞検査士養成コース（900時間）を開講しています。2011年から2年間担当し、1期生、2期生を合わせ、18名が細胞検査士認定試験（日本臨床細胞学会認定資格）に合格し就職していきました。合格率72％（受講生25名）と新規参入のコースとしては健闘しています。今年も13名の学生が細胞検査士養成コースを希望しています。しっかりしごいてできるだけ多く合格させたいと思っています。和歌山県内には臨床検査技師養成の学校はなく、細胞検査士養成のコースもありません。養成コースの学生は、半数が兵庫県以外から集まっています。和歌山県出身の学生も毎年１名程度参加し、卒業後は和歌山で就職する例も多いようです。病院関係者の皆様には、神戸常盤大学学生の臨地実習受け入れ、卒業生の就職など、大変お世話になりありがとうございます。これからも引き続き宜しくお願い申し上げます。 一般に名誉教授となられた先輩の方々は、現職を退いた意識の強い方もおられ、新規の取り組みをあまりされない方もおられるようです。私はそれを避けて、論文発表、学会講演活動も引き続き継続しています。2012年には、以下の英文論文7篇を発表いたしました。日本甲状腺学会が編集するガイドライン『甲状腺結節取扱い診療ガイドライン2013』の作成にも参加しました。これは2年間の編集作業の後、本年南江堂より出版予定です。また自前のホームページ（http://www.kakudok.jp/）に活動報告と第２病理の同門会活動報告、私のライフワークである甲状腺腫瘍診断のコンサルテーション業務も掲載しています。お時間のあるときにご覧いただければ幸いです。 先日は、卒業生に招待され、謝恩会に参加し卒業生だけでなく、お世話になりました皆様とも懐かしいひと時を過ごさせていただきました。和歌山を離れてみますと、和歌山医大の良かったことが懐かしく思い出されます。まだ和歌山に家がありますので、たまには手入れに行きたいと思っています。そのような機会を捕まえてできるだけ和歌山医大の現在を拝見したいと思っています。和歌山医大のご発展と皆様のご健勝を祈念いたします。

1. Kakudo K, Bai Y, Ozaki T et al: Intrathyroid epithelial thymoma (ITET) and carcinoma showing thymus-like differentiation (CASTLE). CD5-positive neoplasms mimicking squamous cell carcinoma of the thyroid. Histol Histopathol, 2012 Dec 11.Epub ahead of print.
2. Kakudo K, Bai Y, Liu Z et al. Encapsulated papillary thyroid carcinoma, follicular variant: a misnomer, Pathol Int. 62(3):155-160, 2012.
3. Kakudo K, Li Y, Taniguchi E et al: IgG4-related disease of the thyroid glands. Endocr J, 59(4):273-281, 2012.
4. Ozaki T, Matsubara T, Kakudo K et al: Thyroid regeneration: characterization of clear cells after partial thyroidectomy.Endocrinology, 153(5):2514-2525, 2012.
5. Li Y, Zhou G, Kakudo K et al: Distinct histopathological features of Hashimoto’s thyroiditis with respect to IgG4-related disease.Mod Pathol, 25:1086-1097, 2012
6. Tang W, Morgan DR, Kakudo K et al: Epstein-barr virus infected gastric adenocarcinoma expresses latent and lytic viral transcripts and has a distinct human gene expression profile.Infect Agent Cancer, 2012 Aug 28; 7(1):21. [Epub ahead of print]
7. Nishigami K, Liu Z, Kakudo K : Cytological features of well-differentiated tumors of uncertain malignant potential: Indeterminate cytology and WDT-UMP. Endocr J, 2012 Jun 30;59(6):483-487, 2012

医学研究に携わって多くの論文を書いてきましたが、研究内容が地味（？）なため、また基礎研究で重箱の隅をつつく内容（？）であるため、今まであまり注目を集めることはありませんでした。また治療に直接関与していないため、患者さんから感謝の言葉をいただいたこともありませんでした。しかし、先週初めて以下のようなmailを、面識のない患者（病院名、患者名は個人情報のため伏せさせていただきます）からいただき、インターネット情報はすごい、研究論文を書くことで患者に情報を発信し、時に役に立っているのだと実感することができ喜んでいます。どのような内容の論文であるか興味のある方はhttp://onlinelibrary.wiley.com/doi/10.1111/j.1440-1827.2011.02773.x/full　をご参照ください。 Dear Dr. Kakudo, I wanted to write and thank you for publishing your comprehensive review of the literature on encapsulated thyroid tumors, and your related papers.  I am referring to Classification of thyroid follicular cell tumors: with special reference to borderline lesions (2011), and Encapsulated papillary thyroid carcinoma, follicular variant: a misnomer, (2012), which make many salient points and provide an excellent review of the literature for both professionals and interested patients. I am a patient who was diagnosed with an encapsulated, mutation-negative, non-invasive thyroid cancer in 2011 in the United States.  The pathology report read that it was an encapsulated classic PTC.  I did wonder a bit at the time whether there could be some kind of question or error about the diagnosis because the tumor did not appear to have been behaving in a way that could be construed as aggressive.  There was no spread to the nodes or outside the thyroid, molecular tests revealed no known genetic mutations and I was also tg undetectable, both basal and stimulated.  I was puzzled, and I did see while looking online that there was some kind of controversy about encapsulated FVPTC, but I was told that I didn’t have FVPTC and also that there are many cases of mutation negative thyroid cancer.  I was also told that I was “low risk” but on the advice of my endocrinologist I submitted to a treatment of radioiodine (50 mCi). Like many or even most patients, when I was diagnosed I really had very little idea of the definition of thyroid cancer according to tumor classification and how that plays into the reasoning of a given pathologist. I had no way of contextualizing “thyroid cancer” in a more meaningful way.  It seems that the hospital that I used treats classic encapsulated PTC the same as garden variety non-encapsulated PTC.  I had no idea that encapsulated PTC could be regarded as being under the same umbrella as encapsulated FVPTC until I did a Google search about it and saw your papers, which elucidate very effectively the problems of inter-observer variation among pathologists and also the questionable ascendency of PTC-N as a major diagnostic criterion.  I would even go beyond that and say that any patient with this type of thyroid tumor who has been diagnosed with cancer and who can read and understand your reports will probably come away feeling rather disturbed, or at the very least disconcerted by the implications.  A cancer diagnosis entails a considerable psychological burden even when the prognosis is good. It really surprised me to learn of the observer-dependent nature of the line between benign and malignant in certain situations.  But I guess what unnerved me the most is the realization that pathologists and other clinicians at times actually do not know with certainty the true nature of some lesions due to the limitations of current knowledge.  Yet these cases will nevertheless often be translated to the patient as definitively being cancer.  How is a patient to react when confronted with this actuality, other than by experiencing a lessening of confidence in the way in which thyroid pathology is being conducted in many hospitals and also with nagging uncertainty about whether their case has been over-treated?  I feel that I was not empowered as a patient and that more transparency is needed in medical practices as to the gaps in understanding in the current classification system, and the resultant gray zones in diagnosis which directly impact the lives of patients like me. It seems to be the case that there is a certain segment of patients who are the unwitting “poster children” of this gray zone in thyroid pathology. My case proceeded on the basis of PTC-N (FNA and pathology) alone because the molecular results were negative.  These uncertainties which have been unmasked by your reports suggest to me that a borderline category based upon degree of invasiveness is a very sensible solution until more hard data becomes available.  At least I can attest to what a difference it would have made to me personally.  Had I known of your research before I had my surgery and treatment, I may have insisted on a lobectomy and almost certainly would not have agreed to receive RAI ablation. Since I saw your papers I conferred with a second pathologist from New England about them, and he confirmed that the diagnosis of these “very low grade lesions” is subjective and sometimes even amounts to a “suggestion” from the pathologist.   I only wish that my original pathologist could have somehow conveyed this information to me. Maybe many pathologists and clinicians in the USA and elsewhere feel that their hands are tied due to legal concerns, but I think that for patients a borderline category makes very good sense and most likely will prevent overtreatment and psychological trauma.  It would have made such a difference for me in that it would have allowed for a lesser degree of treatment while preserving appropriate follow-up. Thank you again, Dr. Kakudo.