{{Short description|Reporting systems for pathology}} '''The Bethesda system''' ('''TBS'''), officially called '''The Bethesda System for Reporting Cervical Cytology''', is a system for reporting [[cervix|cervical]] or vaginal [[Cytopathology|cytologic]] diagnoses,<ref name=AFP-TBS2001 /> used for reporting [[Pap smear]] results. It was introduced in 1988<ref name="pmid2791840">{{cite journal |title=The 1988 Bethesda System for reporting cervical/vaginal cytologic diagnoses: developed and approved at the National Cancer Institute workshop in Bethesda, MD, December 12–13, 1988 |journal=Diagn. Cytopathol. |volume=5 |issue=3 |pages=331–4 |year=1989 |pmid=2791840 |doi= 10.1002/dc.2840050318|last1=Soloman |first1=Diane |s2cid=19684695 }}</ref> and revised in 1991,<ref>{{cite journal | author = Broder S | year = 1992 | title = The Bethesda System for Reporting Cervical/Vaginal Cytologic Diagnoses—Report of the 1991 Bethesda Workshop | journal = JAMA | volume = 267 | issue = 14| page = 1892 | doi=10.1001/jama.1992.03480140014005}}</ref> 2001,<ref name=AFP-TBS2001>{{cite journal |vauthors=Apgar BS, Zoschnick L, Wright TC |title=The 2001 Bethesda System terminology |journal=Am Fam Physician |volume=68 |issue=10 |pages=1992–8 |date=November 2003 |pmid=14655809 |url=http://www.aafp.org/afp/20031115/1992.html |access-date=2009-01-03 |archive-date=2008-09-05 |archive-url=https://web.archive.org/web/20080905045527/http://www.aafp.org/afp/20031115/1992.html |url-status=dead }}</ref><ref>Nayar R, Solomon D. Second edition of 'The Bethesda System for reporting cervical cytology' – Atlas, website, and Bethesda interobserver reproducibility project. CytoJournal [serial online] 2004 [cited 2011 Apr 17];1:4. Available from: http://www.cytojournal.com/text.asp?2004/1/1/4/41272 {{Webarchive|url=https://web.archive.org/web/20181002174906/http://www.cytojournal.com/text.asp?2004%2F1%2F1%2F4%2F41272 |date=2018-10-02 }}</ref><ref name="pmid11966386">{{cite journal |vauthors=Solomon D, Davey D, Kurman R|display-authors=etal |title=The 2001 Bethesda System: terminology for reporting results of cervical cytology |journal=JAMA |volume=287 |issue=16 |pages=2114–9 |date=April 2002 |pmid=11966386 |doi= 10.1001/jama.287.16.2114 |url=http://jama.ama-assn.org/cgi/pmidlookup?view=long&pmid=11966386|url-access=subscription }}</ref> and 2014.<ref>Nayar R, Wilbur D. The Bethesda System for Reporting Cervical Cytology, Definitions, Criteria, and Explanatory Notes. Springer; 2015.</ref> The name comes from the location ([[Bethesda, Maryland]]) of the conference, sponsored by the [[National Institutes of Health]], that established the system.
Since 2010, the Bethesda system has been used for [[cytopathology]] of [[thyroid nodule]]s, which is called '''The Bethesda System for Reporting Thyroid Cytopathology''' (TBSRTC or BSRTC). Like TBS, it was the result of a conference sponsored by the NIH and is published in book editions (currently by Springer). Mentions of "the Bethesda system" without further specification usually refer to the cervical system, unless the thyroid context of a discussion is implicit.
==Cervix== Abnormal results include:{{cn|date=November 2022}} * Atypical squamous cells ** Atypical squamous cells of undetermined significance (ASC-US) ** Atypical squamous cells – cannot exclude HSIL (ASC-H) * Low-grade squamous intraepithelial lesion (LGSIL or LSIL) * High-grade squamous intraepithelial lesion (HGSIL or HSIL) * [[Squamous cell carcinoma]] * Atypical Glandular Cells not otherwise specified (AGC-NOS) * Atypical Glandular Cells, suspicious for AIS or cancer (AGC-neoplastic) * Adenocarcinoma ''in situ'' (AIS)
The results are calculated differently following a [[Pap smear]] of the [[cervix]].{{cn|date=November 2022}}
===Squamous cell abnormalities===
====LSIL: low-grade squamous intraepithelial lesion {{anchor|LSIL}}==== [[File:Cytopathology of low-grade squamous intraepithelial lesion (LSIL).png|thumb|right|Cytopathology of low-grade squamous intraepithelial lesion (LSIL), with main features, as compared to an unremarkable intermediate squamous cell. [[Pap stain]].]] A low-grade squamous intraepithelial lesion (LSIL or LGSIL) indicates possible [[Cervical intraepithelial neoplasia|cervical dysplasia]]. LSIL usually indicates mild dysplasia (CIN 1), more than likely caused by a [[human papillomavirus]] infection. It is usually diagnosed following a [[Pap smear]].{{cn|date=November 2022}}
CIN 1 is the most common and most benign form of cervical intraepithelial neoplasia and usually resolves spontaneously within two years. Because of this, LSIL results can be managed with a simple "watch and wait" philosophy. However, because there is a 12–16% chance of progression to more severe dysplasia, the physician may want to follow the results more aggressively by performing a [[colposcopy]] with [[biopsy]].<ref name=wrightjr2007>{{cite journal | vauthors = Wright TC Jr, Massad LS, Dunton CJ, Spitzer M, Wilkinson EJ, Solomon D|date=Oct 2007|display-authors=etal| title = 2006 consensus guidelines for the management of women with abnormal cervical cancer screening tests | journal = Am J Obstet Gynecol | volume = 197 | issue = 4| pages = 346–55 | doi=10.1016/j.ajog.2007.07.047|pmid=17904957 }}</ref> If the dysplasia progresses, treatment may be necessary. Treatment involves removal of the affected tissue, which can be accomplished by [[Loop electrical excision procedure|LEEP]], [[cryosurgery]], [[cone biopsy]], or laser ablation.{{cn|date=November 2022}}
====HSIL: high-grade squamous intraepithelial lesion {{anchor|HSIL}}==== [[Image:High-grade squamous intraepithelial lesion.jpg|thumb|right|HSIL. [[Pap stain]].]] High-grade squamous intraepithelial lesion (HSIL or HGSIL) indicates moderate or severe [[cervical intraepithelial neoplasia]] or [[carcinoma in situ]]. It is usually diagnosed following a [[Pap test]]. In some cases, these lesions can lead to invasive [[cervical cancer]], if not followed appropriately.{{cn|date=November 2022}}
HSIL does not mean that cancer is present. Of all women with HSIL results, 2%<ref>{{cite journal|vauthors=Massad LS, Collins YC, Meyer PM|title=Biopsy correlates of abnormal cervical cytology classified using the Bethesda system|journal=Gynecologic Oncology|date=Sep 2001|volume=82|issue=3|pages=516-522|pmid=11520149|doi=10.1006/gyno.2001.6323}}</ref> or less<ref>{{cite journal|vauthors=Melnikow J, Nuovo J, Willan AR, Chan BK, Howell LP|title=Natural history of cervical squamous intraepithelial lesions: a meta-analysis|journal=Obstetric Gynecology|date=Oct 1998|volume=92|issue=((4 Pt 2))|pages=727-735|pmid=9764690|doi=10.1016/s0029-7844(98)00245-2}}</ref> have invasive cervical cancer at that time; however, about 20% would progress to having invasive cervical cancer without treatment.<ref>{{cite journal|vauthors=McIndoe WA, McLean MR, Jones RW, Mullins PR|title=The invasive potential of carcinoma in situ of the cervix|journal=Obstetric Gynecology|date=Oct 1984|volume=64|issue=4|pages=451-458|pmid=6483293|s2cid=67962449}}</ref>{{Update inline|date=December 2024|reason=40 year old source}} To combat this progression, HSIL is usually followed by an immediate [[colposcopy]] with [[biopsy]] to sample or remove the dysplastic tissue. This tissue is sent for [[pathology]] testing to assign a [[histology|histologic]] classification that is more definitive than a Pap smear result (which is a [[Cytopathology|cytologic]] finding). HSIL generally corresponds to the histological classification of [[Cervical intraepithelial neoplasia|CIN 2 or 3]].{{cn|date=November 2022}}
HSIL treatment involves the removal or destruction of the affected cells, usually by [[Loop electrical excision procedure|LEEP]]. Other methods include [[cryosurgery|cryotherapy]], cautery, or laser ablation, but none are performed on [[pregnancy|pregnant]] women for fear of disrupting the pregnancy—the indication per 2006 American Society for Colposcopy and Cervical Pathology consensus guidelines being only invasive cancer.<ref name=wrightjr2007/>{{rp|348}} Any of these procedures is 85% likely to cure the problem.{{citation needed|date=March 2026}}
===Glandular cell abnormalities===
====Adenocarcinoma==== [[Image:Adenocarcinoma on pap test 1.jpg|thumb|right|Adenocarcinoma. [[Pap stain]].]] [[Adenocarcinoma]] can arise from the endocervix, endometrium, and extrauterine sites.{{cn|date=November 2022}}
====AGC====
AGC, formerly AGUS, is a term for ''atypical glandular cells of undetermined significance''.<ref>[http://www.emedicinehealth.com/script/main/srchcont_dict.asp?src=AGUS AGUS] {{Webarchive|url=https://web.archive.org/web/20160815060122/http://www.emedicinehealth.com/script/main/srchcont_dict.asp?src=agus |date=2016-08-15 }} at [[eMedicine]] Dictionary</ref> Renamed AGC to avoid confusion with ASCUS.<ref name=AFP-TBS2001 />
The management of AGC is [[colposcopy]] with or without an [[endometrium|endometrial]] [[biopsy]].{{cn|date=March 2023}}
==Thyroid nodules== The ''Bethesda System for Reporting Thyroid Cytopathology'' is the system used to report whether the thyroid cytological specimen is benign or malignant on [[fine-needle aspiration cytology]] (FNAC). It can be divided into six categories: {|class="wikitable" |+ Bethesda system ! Category !! Description !! Risk of malignancy<ref name=Renuka2012>{{cite journal|last1=Renuka|first1=I. V.|last2=Saila Bala|first2=G.|last3=Aparna|first3=C.|last4=Kumari|first4=Ramana|last5=Sumalatha|first5=K.|title=The Bethesda System for Reporting Thyroid Cytopathology: Interpretation and Guidelines in Surgical Treatment|journal=Indian Journal of Otolaryngology and Head & Neck Surgery|pages=305–311|doi=10.1007/s12070-011-0289-4|date=December 2012|pmid=24294568|pmc=3477437|volume=64|issue=4}}</ref> !! Recommendation<ref name=Renuka2012/> |- ! I | Non diagnostic/unsatisfactory || - || Repeating FNAC with ultrasound-guidance in more than 3 months |- ! II | Benign (colloid and follicular cells) || 0 – 3% || Clinical follow-up |- ! III | Atypia of undetermined significance/follicular lesion of undetermined significance (follicular or lymphoid cells with atypical features) || 5 – 15% || Repeating FNAC |- ! IV | Follicular nodule/suspicious follicular nodule (cell crowding, micro follicles, dispersed isolated cells, scant colloid) || 15 – 30% || Surgical lobectomy |- ! V | Suspicious for malignancy || 60 – 75% || Surgical lobectomy or near-total [[thyroidectomy]] |- ! VI | Malignant || 97 – 99% || Near-total [[thyroidectomy]] |}
<gallery mode=packed> File:Thyroid cytopathology of Bethesda category III with clotting artifact.jpg|Thyroid cytopathology of Bethesda category III with clotting artifact File:Thyroid cytopathology of Bethesda category IV.jpg|Category IV File:Thyroid cytopathology of Bethesda category V with intranuclear cytoplasmic inclusion.jpg|Category V with intranuclear cytoplasmic inclusion File:Thyroid cytopathology of Bethesda category V with nuclear groove.jpg|Category V with nuclear groove (arrow) File:Cytopathology suspicious for Hürthle cell neoplasm, annotated.png|Cytopathology suspicious for [[Hürthle cell neoplasm]] (Bethesda category IV, rather than Hürthle cell hyperplasia), Pap stain.<ref>Image by Mikael Häggström, MD. References for findings:<br>- {{cite web|url=https://www.pathologyoutlines.com/topic/thyroidhurthlecellneoplasm.html|title=Hürthle cell neoplasm|website=Pathology Outlines|author=Ayana Suzuki, C.T., Andrey Bychkov, M.D., Ph.D.}} Last author update: 7 May 2020. Last staff update: 12 May 2022<br>- {{cite journal| author=Shawky M, Sakr M| title=Hurthle Cell Lesion: Controversies, Challenges, and Debates. | journal=Indian J Surg | year= 2016 | volume= 78 | issue= 1 | pages= 41–8 | pmid=27186039 | doi=10.1007/s12262-015-1381-x | pmc=4848220 }}</ref> </gallery>
Repeated FNAC is recommended for Category I, followed by clinical follow-up in Category II, repeat FNAC for Category III, and [[lobectomy]] for Category IV, near total-thyroidectomy/lobectomy for Category V, and near total thyroidectomy for Category VI.<ref>{{cite journal|last1=Renuka|first1=I.V|last2=Saila Bala|first2=G|last3=Aparna|first3=C|last4=Kumari|first4=R|last5=Sumalatha|first5=K|title=The Bethesda System for Reporting Thyroid Cytopathology: Interpretation and Guidelines in Surgical Treatment|journal=Indian J Otolaryngol Head Neck Surg|date=December 2012|volume=64|issue=4|pages=305–311|doi=10.1007/s12070-011-0289-4|pmc=3477437|pmid=24294568}}</ref> The risk of malignancy in a malignant FNAC report is 93.7% while for a suspicious FNAC report, it is 18.9%.<ref>{{cite journal|last1=Tee|first1=Yoon Y|last2=Lowe|first2=Adrain J|last3=Brand|first3=Caroline A|title=Fine-Needle Aspiration May Miss a Third of All Malignancy in Palpable Thyroid Nodules|journal=Annals of Surgery|date=November 2007|volume=246|issue=5|pages=714–720|doi=10.1097/SLA.0b013e3180f61adc|pmid=17968160|s2cid=30354862|quote=our study showed that the risk of malignancy of malignant FNA and suspicious FNA diagnosis is around 93.7% and 18.9%, respectively.}}</ref>
== See also == * [[American Society for Clinical Pathology]]
== References ==
{{reflist|30em}}
== External links == * [https://web.archive.org/web/20081223051738/http://nih.techriver.net/ ASCP: The Bethesda System Website Atlas] * [https://web.archive.org/web/20090114020353/http://www.bethesda2001.cancer.gov/ Bethesda 2001 Workshop] *{{cite journal |last1=Bongiovanni |first1=Massimo |last2=Spitale |first2=Alessandra |last3=Faquin |first3=William C. |last4=Mazzucchelli |first4=Luca |last5=Baloch |first5=Zubair W. |title=The Bethesda System for Reporting Thyroid Cytopathology: A Meta-Analysis |journal=Acta Cytologica |date=2012 |volume=56 |issue=4 |pages=333–339 |doi=10.1159/000339959 |pmid=22846422 |s2cid=14143335 |url=http://www.thyroid.org/professionals/ata-publications/clinical-thyroidology/january-2013-volume-25-issue-1/clin-thyroidol-20132516-17/ |access-date=24 November 2022|doi-access=free }} {{Human papillomavirus}}
[[Category:Diagnostic endocrinology]] [[Category:Gynaecological cancer]] [[Category:Medical terminology]] [[Category:Papillomavirus-associated diseases]] [[Category:Pathology]] [[Category:Thyroid]] [[Category:Cervical cancer]] [[Category:Bethesda, Maryland]]