Collision tumor of kidney: A case of renal cell carcinoma with metastases of prostatic adenocarcinoma

Abstract

Simultaneous occurrence of prostatic adenocarcinoma and renal cell carcinoma is well documented in the literature. However, metastatic prostatic adenocarcinoma in a kidney harboring a renal cell carcinoma (RCC) is quite rare. Although renal cell carcinoma is the most common tumor that can harbor metastasis, metastatic prostatic adenocarcinoma in a kidney harboring a RCC is quite rare. There are four cases in the literature showing metastasis of prostatic adenocarcinoma to RCC. However, as per our knowledge, this is the first case of a collision between RCC and metastatic prostatic adenocarcinoma.

Collision metastasis: Renal cell carcinoma and prostatic adenocarcinoma to a retroperitoneal lymph node

“…In general, the definition differs on whether a transitional pattern is allowed at the site of collision of mixed structure, as that could suggest a composite tumor. 4 The collision metastasis found within the patient portrays distinct borders with histologic staining providing evidence of true collision metastasis.…”

“…(4) Concurrent growth of separate cell lines within the same organ. 3 , 4 The patient's history of prostatic adenocarcinoma begs the question of an alteration of a microenvironment from the recurrence of prostate cancer; however, the retroperitoneal lymph node in question is not a common location for prostate cancer to metastasize. The chance meeting of two primary tumors is also a possibility, as was hypothesized by Vyas et al due to the high vascularity of RCCs and the minute volume received by the kidneys.…”

“…Collision metastasis is defined as two histologically distinct malignant neoplasms appearing simultaneously within the same organ "colliding” with one another from separate topographical primaries. 4 We present a case report of metastasis of RCC and prostatic adenocarcinoma to a retroperitoneal lymph node in a 50-year-old male.…”

“…To our knowledge, this appears to be the second case of collision metastasis of prostatic adenocarcinoma and RCC reported in the literature. 4 …”

Collision tumor of bone: primary chondrosarcoma of bone as a rare recipient of tumor-to-tumor metastasis from metastatic breast carcinoma

“…Collision tumors represent the rare phenomenon in which two or more distinct and unrelated tumors reside concurrently in one location as either both primary tumors [1] , one primary and one metastatic tumor (also known as "tumor to tumor metastasis") [2] or both metastatic tumors [3] . We report an unusual case of a collision tumor involving metastatic breast adenocarcinoma and primary grade 1 chondrosarcoma occurring in the femur of a 58-year-old female patient.…”