Cancer of unknown primary site (CUP) constitutes approximately 5% of all cancers [1,2]. It is defined as a histologically confirmed metastatic tumor in which the primary source remains unknown despite comprehensive clinical evaluation and diagnostic work-up. Most are aggressive with poor prognosis. Metastatic inguinal lymphadenopathy originates from the genitalia and anorectal areas. This case report describes an uncommon case of two different histological types of metastases in inguinal nodes with unknown primary sites.

•A 65 year old gentleman, ECOG 0, with hypertension, bidi smoker 5 pack year, and tobacco chewer since 3 years, presented with right inguinal swelling since 2 years, gradually progressive in nature. •On examination, 5x3 cm multiple matted LN palpable at right inguinal region, mobile , non tender. No growth/ ulcer over penis scrotum or B/L lower limb. •MRI PELVIS suggestive of partially necrotic three LN in Rt inguinal region largest 43x35 mm, possibility of neoplastic secondary deposit. CECT suggestive of enlarged heterogeneously enhancing necrotic LN 41x27 mm in right inguinal region. FDG PET SCAN suggestive of metabolically active few enlarged necrotic right inguinal LN.

•Underwent FNAC s/o metastatic SCC, For better categorization, underwent incisional biopsy s/o metastatic SCC , CK 7 -ve, CK 20-ve, GATA3 mild focal positivity,p40 +ve. Slide review s/o metastatic deposit of urothelial carcinoma Ck7 –ve, CK 20-ve, p40 +ve, p60 +ve, GATA3 +ve. •Serum CEA, CA19-9, AFP, PSA, and beta HCG were within normal range. •Urine cytology for malignant cell -ve, Gene X pert :- MTB not detected •CPE+ urethroscopy:- normal study. •Tumor board discussion done. •Underwent Right std PLND + Right radical ILND. Hpe s/o Metastatic SCC, P40, P63 +ve, HMB 45 & GATA -ve . Right PLN- no evidence of mets (0/4), Right Superficial ILN- 2/7 +ve for mets, Right Deep ILN- 1/2 +ve for mets.

Carcinoma of unknown primary with inguinal metastasis is a rare entity. Although there are no clear guidelines for the management of such patients, treatment should be multimodal, including aggressive surgical resection and postoperative radiotherapy. The possible role of chemotherapy is unknown. A diligent follow-up is a must. In the future, molecular studies may increase our ability to distinguish subtypes of CUP and treat them differentially.