Chapter 3: Skin, Breast, and Nail Changes

Some visible changes are easier to notice than internal symptoms, but they can still be misunderstood.

The skin and nails can change for countless harmless reasons. A new spot or nail mark is not automatically a sign of cancer.

What matters is whether the change is new, unusual, persistent, or evolving.

7. A Changing Mole or Skin Lesion

One of the most important skin warning signs is a mole or pigmented lesion that changes.

Doctors often use the ABCDE approach when assessing suspicious moles:

• A — Asymmetry: one half looks different from the other.
• B — Border: edges are irregular, uneven, or poorly defined.
• C — Color: multiple or unusual colors appear within the lesion.
• D — Diameter: larger lesions may deserve closer assessment, although melanoma can occur in smaller lesions too.
• E — Evolving: the spot changes in size, shape, color, or appearance.

A lesion that repeatedly bleeds, crusts, itches, or fails to heal can also deserve professional evaluation.

8. Persistent Breast Changes

Breast cancer does not always begin with a noticeable lump.

Possible warning signs can include a new lump, swelling, changes in breast shape, skin dimpling, persistent nipple changes, nipple discharge, or a newly inverted nipple.

Many breast changes are benign and may be related to hormonal fluctuations, cysts, infections, or other non-cancerous conditions.

But a new persistent change should still be checked.

Women should become familiar with what is normal for their own breasts. This makes it easier to recognize something genuinely different.

Recommended breast screening also plays an important role because some cancers can be detected before symptoms appear.

9. A New Dark Streak Under a Nail

A dark vertical streak beneath a fingernail or toenail can have several causes.

Trauma, pigmentation, medications, benign moles, and other conditions can produce dark nail changes.

Rarely, melanoma can develop beneath the nail.

One reason doctors may pay attention to a new or changing dark streak is that pigment may sometimes extend onto the surrounding skin near the nail.

The important point is that a nail streak does not automatically mean melanoma.

However, a new, unexplained, or changing pigmented streak should be examined rather than diagnosed through an internet image.