Japan: Study Links Low Psoas Muscle Volume to Poor Prognosis in Penile Cancer

According to a recent study in the journal Oncotarget, a low volume of the psoas muscle is associated with poor prognosis in penile cancer.

Sarcopenia is a condition characterized by low muscle volume due to aging. Recently, it has been studied as a risk factor predicting an increased risk of postoperative complications and longer hospitalization. Previous studies have shown the importance of sarcopenia as a risk factor for poor survival in renal and bladder cancer.

Penile cancer accounts for only 0.5% of all cancers in men. Lymph node metastatic cases show a poor prognosis, while localized penile cancer tends to have a relatively favorable outcome. However, with complete resection of the metastatic lymph node, even cases of lymph node metastasis can show a favorable outcome.

A previous study has shown a higher incidence of postoperative complications in sarcopenic penile cancer patients who underwent inguinal lymph node dissection than patients without sarcopenia. Daiji Takkamoto, Yokohama City University Medical Center, Yokohama, Japan, and colleagues therefore examined the importance of sarcopenia as a new prognostic marker in penile cancer.

The study analyzed a total of 25 patients diagnosed with penile cancer who underwent penile resection from 2000 to 2010. Based on the psoas area, the researchers calculated the psoas muscle index (PMI) using preoperative axial computed tomography images at the right L3 level divided by the square of the body height.

76.0% of the patients underwent partial penectomy, and 24.0% underwent total penectomy. The median age was 69.3 (69.0 ± 10.1) years old.

Key Findings of the Study

• Regarding the site of penile cancer, 76.0% of cases were in the glans, 24.0% were in the foreskin, and 8.0% were in the shaft.
• Lymph node metastasis was seen in 6 cases (24.0%), and distant metastasis was seen in 1 case (4.0%).
• The lower PMI group (< 320.0) showed a significantly poorer progression-free survival than the higher PMI group (≥ 320.0), although no significant difference in the overall survival was noted.

"Sarcopenia might be a useful prognostic factor in penile cancer patients," concluded the authors.

The study, "A low psoas muscle volume is associated with a poor prognosis in penile cancer," is published in the journal Oncotarget.

DOI: https://www.oncotarget.com/article/27719/text/