Clinico-pathological implications of the 2022 WHO Renal Cell Carcinoma classification

The new WHO classification of urogenital tumours published in 2022, contains significant revisions upon the previous 2016 version regarding Renal Cell Carcinoma (RCC). While the most common histotype remains almost untouched, some of the main novelties concerns papillary RCC and oncocytic neoplasms. The main change is the introduction of a new category of molecularly-defined RCC, which includes TFE3-rearranged RCC, TFEB-rearranged, and TFEB-amplified RCC, FH-deficient RCC, SDH-deficient RCC, ALK-rearranged RCC, ELOC (formerly TCEB1)-mutated RCC, SMARCB1 (INI1)-deficient RCC. In this paper we analyze the current knowledge on emerging entities and molecularly-defined RCC to assess whether the current pathological classification offers the oncologist the possibility of selecting more specific and personalized treatments, from both those currently available, as well as those that will soon be available.

Primary lymphoma of the kidney. Report of a case and update of the literature

OBJECTIVES

To report on a case of primary renal lymphoma (PRL) and update the literature concerning this topic.

MATERIALS AND METHODS

A 48-year-old woman underwent surgery for the presumed diagnosis of renal cell carcinoma with bilateral adrenal metastases.

RESULTS

The neoplasm was assessed as primary renal non-Hodgkin high grade lymphoma, diffuse large B-cell type. Then the patient underwent polychemotherapy according to the VACOP-B protocol. Unfortunately, 5 weeks later the patient was lost since missing chemotherapy and follow-up.

CONCLUSIONS

PRL is a distinct pathological and clinical entity which is extremely rare and highly aggressive since disseminating rapidly from its origin. The disease usually affects adults with an average age of 60 years and slight male preponderance; however it has also been reported in childhood. Etiology factors for PRL are unknown. Several histogenetic theories of the disease have been postulated since the kidney does not normally contain lymphoid tissue. Investigators reported many classes of non-Hodgkin lymphoma which include large, small, intermediate and mixed cell types with high, intermediate or low grade histologies. The neoplastic lymphoid cells may express both B and T immunoblastic phenotypes, primary renal Hodgkin lymphoma has also been reported. The disease may present with progressive renal failure of either oliguric or non oliguric type. Imaging studies in diagnosing and staging primary renal lymphomas include ultrasound examination (US) and computed tomography (CT); there are also some reports of magnetic resonance imaging (MRI). Total body bone scan and bone marrow biopsy will complete disease clinical staging. Renal biopsy is important in assessing the diagnosis of PRL as well as of acute renal failure for bilateral lymphomatous infiltration of the kidneys. Up to now, there are no standard treatment modalities for this entity since the small number of cases reported. Multidrug chemotherapy is mandatory for high grade lymphoma and when the disease is diagnosed preoperatively. High dose chemotherapy in the future may offer a curative approach in primary bilateral renal disease and without end-stage renal disease. Survival is extremely poor since 75% of patients die less than 1 year after operation. Prognosis may be improved by early detection of disease and by performing systemic chemotherapy.