‘PTNM’ system provides new classification for Peyronie’s disease and penile curvature

Analysis of men seen at a specialist clinic provides new insights into the classification of Peyronie’s disease (PD) subtypes, according to a report in the September issue of the Journal of Urology, an Official Journal of the American Urological Association (AUA). The journal is published in the Lippincott portfolio by Wolters Kluwer.

“By analyzing real-world clinical data in a large group of patients, we identified four distinct subtypes of PD, and additional categorization of other causes of penile curvature,” comments Landon Trost, MD, of Male Fertility and Peyronie’s Clinic in Orem, Utah. “We propose a new classification system, which we believe will provide a more consistent and standardized approach to classification and treatment of PD.”

Evidence-based approach to Peyronie’s disease classification

Peyronie’s disease is a condition in which the penis becomes curved due to scar-like tissue called plaque. Some men experience pain, erectile dysfunction, or sexual dysfunction. Typically, PD is characterized by palpable plaque and curvature occurring in men in their fifties and sixties (The Urology Care Foundation has a Peyronie’s disease fact sheet).

However, even in men with these “classical” findings, symptoms of PD may vary widely. Some men may develop a sudden curve, with no other symptoms, that remains stable over time; while others may experience ongoing pain and progression of the deformity. In the absence of more specific criteria, men with penile curvature of any cause are often diagnosed with PD.

To identify patterns and clinical subtypes of PD, Dr. Trost and colleagues analyzed clinical data on 1,098 men with confirmed penile deformity evaluated at the clinic from 2020 to 2023. In a second sample, secondary deformity or curvature was reported by 18 of 162 responding to a long-term follow-up survey.

Proposed system a ‘notable advancement’ in PD research and treatment

Statistical analysis of the data identified four distinct subtypes of PD: three “non-classical” subtypes defined by the presence of calcifications, progression (worsening curvature), or a relapsing/remitting pattern; and a “classical” subtype with none of these features. Men with classical PD had some distinct characteristics, including older age, more stable curvature, and fewer problems with pain.

In addition, the researchers identified three non-PD categories: congenital (lifelong), maturational (developing around puberty), and trauma-induced penile curvature. The progressive pattern was the most common finding, seen in 57% of patients. Classical PD and trauma-induced, non-PD penile curvature were each found in 27% of patients. (Some patients had overlapping subtypes, falling into multiple categories.)

Surprisingly, pain was not a reliable predictor for either progression or stability of the penile curvature. Analysis of follow-up data suggested that the distinction between stable and progressive PD can be made after three months’ follow-up. Longer follow-up—at least six months—was needed to identify relapsing-remitting PD.

Dr. Trost and colleagues propose a “PTNM” classification system made up of four factors: the subtype of PD, history of trauma, non-PD subtype, and stable or active mode during follow-up. This system “allows for a more consistent and standardized method of classifying PD and communication among health care professionals.”

“Pending external validation, these findings represent a notable advancement for the field of PD,” the researchers add. They note that the patients in their study may not reflect the broader population of men with PD or non-PD penile curvature.

“We believe our proposed PTNM system will be clinically helpful in the evaluation and management of men with penile curvature,” Dr. Trost comments. “This information has the potential to improve prognostic information, enhance patient counseling, and facilitate treatment decision-making for patients with PD, as well as guiding further research.”