Simon Classification — Matching Grade to Technique

By Assoc. Prof. Dr. Ayhan Işık Erdal, MD, FACS, FEBOPRAS · Updated April 2026
Key takeaway

The Simon classification (1973) grades gynecomastia into four levels — Grade I (minor, no skin excess), IIa (moderate, no skin excess), IIb (moderate, minor skin excess), and III (marked enlargement with skin excess). The grade is the single most important variable in technique selection. Liposuction or pull-through suits Grade I–IIa; gland excision is needed for IIb–III; only Grade III routinely requires skin excision and nipple-areolar repositioning.

The Simon classification (Simon, Hoffman & Kahn, 1973) is the most widely used grading system for gynecomastia. Five decades after its publication it remains clinically relevant because it directly maps severity to surgical technique. This guide walks through each grade, the physical findings that distinguish them, and the technique typically indicated for each.

Why classification matters: choosing the operation before grading the disease produces over-treatment (unnecessary scars in Grade I) or under-treatment (recurrent gland in Grade IIb handled as Grade I). The grade should be assigned at the first clinical examination, photographed, and driven into the surgical plan — not modified on the operating table.

Grade I — Minor enlargement, no skin excess

The subtlest presentation. A small button of glandular tissue (typically 2–4 cm in diameter) lies directly behind the nipple-areolar complex, often with a modest surrounding fat component. Skin envelope is appropriate to the reduced contour after tissue removal — no skin excess, no nipple displacement. Often missed clinically until the patient points it out.

Physical findings:

Recommended technique: Liposuction (if predominantly fat) or pull-through technique (if significant fibrous gland). The pull-through avoids a formal periareolar incision while still addressing the gland.

Grade IIa — Moderate enlargement, no skin excess

The most common presentation in adult men and the technical "sweet spot" for gynecomastia surgery. Clear visible protrusion (the patient avoids fitted shirts, bench press photos, etc.), mixed glandular-fatty composition, but skin tone remains sufficient to retract after tissue removal.

Physical findings:

Recommended technique: Pull-through technique for mixed composition, or formal gland excision via inferior periareolar incision if the gland is dense / fibrous. Liposuction is the adjunct, not the primary modality in true Grade IIa.

Grade IIb — Moderate enlargement with minor skin excess

The borderline grade — sometimes called "2b" in shorthand. Tissue volume is similar to IIa but skin has stretched slightly beyond its elastic capacity. Skin will partially retract after resection, but not to the ideal male chest contour. Conservative periareolar skin excision delivers a better final result than relying on retraction alone.

Physical findings:

Recommended technique: Gland excision via periareolar incision, combined with conservative crescent-shaped skin excision at the inferior areolar border to tighten and slightly lift the nipple-areolar complex. Approximately 2–4 mm of skin removal is typical.

Grade IIb vs. IIa — the decisive examination point

The differentiator is the pinch-and-release test at the inferior areolar border. Pinch the skin at the 6 o'clock position of the areola, then release: in Grade IIa, the skin returns within 1 second; in Grade IIb, there is visible delay (2–4 seconds) or a residual fold. This single finding changes the operation — and honestly telling the patient pre-operatively that they will have a slightly larger scar is better than surprising them intra-operatively.

Grade III — Marked enlargement with significant skin excess

True breast-like appearance with glandular ptosis (sagging) and inferior displacement of the nipple-areolar complex below the inframammary fold. Skin excess is significant and does not retract meaningfully. The operation becomes a skin-driven case rather than a gland-driven one.

Physical findings:

Recommended technique: Gland excision combined with formal skin excision and nipple-areolar repositioning. Incision pattern is commonly circumareolar (for mild Grade III) or a modified vertical/anchor pattern (for severe Grade III) — borrowing from the breast reduction surgical vocabulary. This is the only grade where an obvious surgical scar is anatomically unavoidable.

Grade summary table

GradeTissueSkinTechniqueTypical scar
IMinor, mostly glandNormalLiposuction ± pull-through3–4 mm puncture
IIaModerate, mixedNormal, retractilePull-through or gland excisionPeriareolar arc (hidden)
IIbModerateMinor excessGland + conservative skinPeriareolar + crescent
IIIMarkedSignificant excessSkin excision + NAC repositioningCircumareolar ± vertical

Alternative classifications

Several other systems exist; Simon remains the most cited. Rohrich (2003) proposed a modified system incorporating tissue composition (glandular vs. adipose dominant) as a separate axis — useful in research contexts. Cordova-Moschella (2008) emphasised the role of the inframammary fold and nipple position for Grade III planning. Most working surgeons use Simon as the base language and mentally apply Rohrich's glandular/adipose distinction when planning.

Key references

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Frequently asked questions

What is the Simon classification of gynecomastia?

The Simon classification, developed by Simon, Hoffman and Kahn in 1973, grades gynecomastia by tissue volume and skin redundancy. Grade I is minor enlargement without skin excess. Grade IIa is moderate enlargement without skin excess. Grade IIb is moderate enlargement with minor skin excess. Grade III is marked enlargement with significant skin excess requiring skin excision and nipple repositioning.

Can I determine my own Simon grade from photos?

Approximate self-assessment is possible: assess (1) chest fullness severity from front and oblique angles, (2) whether skin appears stretched or loose, (3) nipple position. However, accurate grading requires physical examination — the firm-versus-soft consistency on pinch test, true skin elasticity, and presence of a discrete glandular disc cannot be assessed reliably from photographs alone. Send photos for surgeon assessment rather than self-grading.

Can my Simon grade change between consultation and surgery?

The grade itself does not change — your anatomy is your anatomy — but the technique chosen for it can be refined intraoperatively if the surgeon finds the gland is denser or skin elasticity is different from external assessment. The grade should be assigned at the first clinical examination, photographed, and used to plan surgery. Adjustments on the operating table are technique adjustments, not grade reclassifications.

Is Simon classification still used in 2026?

Yes — Simon classification remains the most widely used grading system in gynecomastia surgery globally. While newer classifications (Rohrich, Cordova, Cohn-Stuart) have been proposed for specific clinical contexts, Simon's framework remains the reference for technique selection because it directly maps severity to surgical approach in a way that has stood five decades of validation.