de la Barreda F, Sánchez-Armendáriz K, Zárate-Flores L, García-Galaviz R, Toussaint-Caire S

Language: Spanish
References: 22
Page: 397-401
PDF size: 137.71 Kb.

ABSTRACT

Introduction: the number necessary to excise (NNE) is a concept used for evaluating clinical accuracy in melanoma diagnosis. It measures how many pigmented lesions have to be excised to diagnose one melanoma. A low NNE means that fewer benign lesions are unnecessarily removed. This number has been reported as high as 83 for general practitioners and between 2.7 and 15 for experienced dermatologists. The melanoma to melanoma in situ (MM /MIS) ratio is an additional measure designed to encourage clinicians to detect melanoma at an early stage.
Patients and methods: We investigated the nne and MM /MIS in a group of patients seen by a dermatologist in a private office from February 1 2018 to February 1 2019. nne was also evaluated separately in three subsets of patients according to reason for consulting: patients who came for cancer screening and had a total body skin examination (TBSE), patients who consulted for a specific pigmented lesion (SPL) and patients that consulted for a different skin problem but in whom a suspicious pigmented lesion was found during clinical exam as an incidental finding (IF).
Results: in the time frame of one year, 341 patients were evaluated for pigmented lesions. Biopsies were performed in 23 (6.7%), melanoma was diagnosed in six. Our NNE was 3.8, the MM /MIS ratio was 3. In the TBSE group seven biopsies were taken to 216 patients and none of them was melanoma, so the nne could not be calculated, but it would be at least seven. Ninety patients consulted for a SPL, 12 biopsies were taken and five melanomas were found. The NNE in this group was 2.4. In the if group, four biopsies were performed in 36 patients. Melanoma was diagnosed in one, the NNE = 4.
Discussion: the nne has several drawbacks, the most important is that it does not measure sensitivity and, furthermore, trying to achieve a low NNE might result in a decreased sensitivity. However, it is the only measure of our clinical skill to diagnose melanoma and it can be a good method to evaluate our performance. The MM /MIS ratio is a useful tool to avoid that the aim of a low nne results in decreased sensitivity.
Conclusions: our NNE of 3.8 and MM /MIS ratio of 3 are in the lower range of the average reported by other groups or clinicians. Our analysis of subsets of patients suggest that lower NNE are obtained in patients that consult for a SPL or in those in which the suspicious lesion was discovered as an if than in patients who underwent a tbse for cancer screening.

REFERENCES

1. American Cancer Society, Cancer facts and figures 2020, Atlanta, American Cancer Society, 2020. Disponible en línea.

2. Balch CM, Soong S, Ross MI et al., Long-term results of a multi-institutional randomized trial comparing prognostic factors and surgical results for intermediate thickness melanomas (1.0 to 4.0 mm), Intergroup Melanoma Surgical Trial, Ann Surg Oncol 2000; 7(2):87-97.

3. Rolfe HM, Accuracy in skin cancer diagnosis: a retrospective study of an Australian public hospital dermatology department, Australas J Dermatol 2012; 53:112-7.

4. Argenziano G, Cerroni L, Zalaudek I, Staibano S, Hoffmann-Wellenhof R, Aroaia N et al., Accuracy in melanoma detection: a 10-year multicenter survey, J Am Acad Dermatol 2012; 67:54-9.

5. Antonio JR, Soubhia RM, D’Avila SC, Caldas AC, Trídico LA y Alves FT, Correlation between dermoscopic and histopathological diagnoses of atypical nevi in a dermatology outpatient clinic of the Medical School of São José do Rio Preto, SP, Brazil, Anais Brasileiros de Dermatologia 2013; 88(2):199-203.

6. Esdaile B, Mahmud I, Palmer A y Bowling J, Diagnosing melanoma: how do we assess how good we are?, Clin Exp Dermatol 2014; 39(2):129-34.

7. Kofler R, Egger M y Kofler H, Suspicious melanocytic lesions: number needed to treat to identify a melanoma, Clinical Dermatol 2014; 2:73-6.

8. English DR, Del Mar C y Burton RC, Factors influencing the number needed to excise: excision rates of pigmented lesions by general practitioners, Med J Aust 2004; 180(1):16-9.

9. Sidhu S, Williams N y Roberts DL, The number of benign moles excised for each malignant melanoma: the number needed to treat, Clin Exp Dermatol 2012; 37:6-9.

10. Chia A, Simonova G, Dutta B, Lim A y Shumack S, Melanoma diagnosis: Australian dermatologists’ number needed to treat, Australasian J Dermatol 2008; 49:12-5.

11. Wilson RL, Yentzer BA, Isom SP, Feldman SR y Fleischer AB, How good are US dermatologists at discriminating skin cancers? A number- needed-to-treat analysis, J Dermatol Treat 2012; 23:65-9.

12. Ahnlide I, Nielsen K y Biellerup M, Diagnosis of pigmented skin tumours in a dermatological setting: different aspects of the number needed to excise as a measure of efficiency, Acta Derm Venereol 2014; 94:683-6.

13. Gilmore S, Melanoma screening: informing public health policy with quantitative modelling, plos One 2017; 12(9): e0182349.

14. Johansson M, Brodersen J, Gøtzsche PC y Jørgensen K, Screening for reducing morbidity and mortality in malignant melanoma, Cochrane Database Syst Rev 2016; 2016(9):cd012352.

15. Oliveira SA, Heneghan MK, Cushman LF, Ughetta EA y Halpern AC, Skin cancer screening by dermatologists, family practitioners, and internists: barriers and facilitating factors, Arch Dermatol 2011; 147(1):39-44.

16. Rembold CM, Number needed to screen: development of a statistic for disease screening, bmj 1998; 317:307.

17. Rat C, Quereux G, Grimault C, Gaultier A, Khammari A, Dreno B y Nguyen JM, Melanoma incidence and patient compliance in a targeted melanoma screening intervention. One-year follow-up in a large French cohort of high-risk patients, European Journal of General Practice 2015; 21(2):1-7.

18. Watts CG, Cust AE, Menzies SW, Mann GJ y Morton RL, cost-effectiveness of skin surveillance through a specialized clinic for patients at high risk of melanoma, J Clin Oncol 2017; 35(1):63-71.

19. Guitera P, Menzies SW, Coates E, Azzi A, Fernández-Penas P, Lilleyman A, Badcock C, Schmid H, Watts CG, Collgros H, Liu R, Van Kemenade C, Mann GJ y Cust AE, Efficiency of detecting new primary melanoma among individuals treated in a high-risk clinic for skin surveillance, jama Dermatol 2021; 157(5):521-30.

20. Sgubbi P, Savola F, Dika E, Neri I, Fanti PA y Patrizi A, Melanoma and melanocytic nevi in pediatric patients: a single institution experience, G Ital Dermatol Venereol 2019; 154:14-7.

21. Alarcón J, Carrera C, Palou J, Alos L, Mavehy J y Puig S, Impact of in vivo reflectance confocal microscopy on the number needed to treat melanoma in doubtful lesions, Br J Dermatol 2014; 170:802-8.

22. Rivers JK, Copley MR, Svoboda R y Rigel DS, Non-invasive gene expression testing to rule out melanoma, Skin Therapy Lett 2018; 23(5):1-4.