Prospective validation of clino-radio-pathological risk scoring system (CRiSS) for prediction of inguinal lymph-nodes metastasis in squamous cell carcinoma of penis.

Objective: To prospectively validate the diagnostic performance of Clino-radio-pathological Risk Scoring System (CRiSS) for prediction of inguinal lymph-node metastasis (ILNM) in squamous cell carcinoma of penis.

Materials and methods: A prospective observational study of all patients with SCC penis was conducted between January 1, 2021, and December 31, 2023, at our institute. Data regarding all CRiSS parameters and MRI features of >8mm size and presence of necrosis or irregular outline were recorded, and patients were assigned CRiSS scores and groups. All included patients were subjected to primary surgery (partial/total penectomy) along with bilateral radical inguinal lymph-node dissection. Multivariate logistic regression analysis was performed with both USG and MRI. Sensitivity and specificity were calculated for CRiSS scores and groups.

Results: A total of 86 patients were enrolled during the study period. Size of lymph-node greater than 8mm (HR: 4.502) and irregular outline or presence of necrosis (HR: 4.002) in MRI were significantly associated with ILNM along with all other CRiSS variables in multivariate analysis. CRiSS groups had a sensitivity of 100% and a specificity of 85.71%. CRiSS could diagnose ILNM with a sensitivity of 100% in both palpable and non-palpable groins.

Conclusions: CRiSS can identify patients in whom ILND can be avoided with a zero false negative rate, irrespective of clinical lymph-node status. CRiSS can identify the patients who are candidates for ILND even after a negative FNAC and biopsy of palpable lymph-nodes. It can identify patients for concomitant penectomy and ILND. MRI is a suitable replacement for ultrasonography if not standard of care (CRiSS-M).