Because skin metastasis is usually asymptomatic, conducting thorough skin assessments is critical for timely diagnosis of internal malignancy.
In fact, “skin metastasis may be the first sign of internal malignancy,” writes Mellisa Hall, DNP, AGPCNP-BC, chair of the master of science in nursing program at the University of Southern Indiana in Evansville, in The Journal for Nurse Practitioners.
Criteria to identify the primary malignancy site are the location of the skin change and the patient’s age and gender.
New single or multiple skin lesions will likely rapidly change, with changes often firm, mobile and rubbery in texture, akin to benign skin lesions.
Flesh is the most common color of lesions. The incidence of cutaneous metastasis has also been reported in up to 9% of patients with metastatic cancer.
For women with breast cancer, the skin change is limited to one breast. These women may present with erythematous changes comparable to cellulitis or with prominent telangiectatic blood vessels. Others may have a dry, scaly, orange peel-like appearance.
The skin lesions of men with lung cancer, on the other hand, are frequently found on the anterior/posterior chest and the abdomen.
For all cancers, including colon, stomach, pancreas and pelvis, a full-body skin assessment entails a fundoscopic exam for pigment changes of the retina, nails, interdigital skin between toes, vaginal tissue and anal regions.
Skin assessments should also include inspection of surgical scars from previously removed malignancies.
Hall notes that the changing skin of acanthosis nigricans, seborrheic keratoses, erythroderma, pemphigoid and vasculitis “can be associated with internal malignancies, and may appear years before diagnosis of the primary malignancy.”
Documentation of skin findings should include the location, color and size of the lesion and any distribution pattern for multiple lesions.
In addition, sufficient lighting is needed to detect subtle changes in vascularity or scabbing. Palpating the lesion for tenderness or induration is also important because induration is linked to malignancy, especially on the scalp.
Finally, the probability of melanoma recurrence is possible with an immune complex assay that has 70% sensitivity and 85% sensitivity.
Mellisa Hall, DNP, AGPCNP-BC. “Intentionality in skin assessment: identifying internal cancer externally,” The Journal for Nurse Practitioners. Volume 13, Issue 6, June 2017. DOI:http://dx.doi.org/10.1016/j.nurpra.2017.03.014