Spontaneous regression of biopsy proven primary renal cell carcinoma: A case study

Efficacy of 18F-Fluorodeoxyglucose positron emission tomography/computed tomography for detecting renal cell carcinoma in patients with end-stage renal disease

PURPOSE

Dialysis patients are at an increased risk of developing renal cell carcinoma (RCC); however, differentiating between RCC and benign cysts can sometimes be difficult using modalities, such as computed tomography (CT) and ultrasonography. 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET)/CT efficiently detects malignant tumors; however, physiological accumulation of FDG in the kidney limits its efficacy in detecting renal tumors. However, in patients with severely impaired renal function, the renal accumulation of FDG is decreased, possibly improving the detection of renal malignancies in this patient population. This study evaluated the usefulness of FDG-PET/CT as a screening tool for detecting RCC in patients with end-stage renal disease.

MATERIALS AND METHODS

This prospective study recruited 150 participants from 2012 to 2016 who were on dialysis or underwent renal transplantation and were on dialysis until transplantation. FDG-PET/CT was performed to screen for RCC. Three radiologists independently evaluated the images. No protocol was defined for the additional management of positive examinations, leaving decisions to the discretion of each participant. Negative examinations were observed until the end of 2019.

RESULTS

In total, 150 participants (mean age, 58 ± 13 years; 105 men) underwent FDG-PET/CT. Twenty patients (13.4%) were diagnosed as positive. Fifteen patients underwent additional examinations and/or procedures, and RCC was found in seven patients. Of the four patients who underwent surgical resection, the pathological results were clear cell RCC in one, papillary RCC in one, and acquired cystic disease-associated RCC in two. Two participants were diagnosed with RCC on bone biopsy, and one was diagnosed on dynamic CT but opted for observation. The sensitivity, specificity, and negative predictive value were 100%, 93.9%, and 100%, respectively.

CONCLUSION

FDG-PET/CT was useful for detecting RCC in patients with end-stage renal disease. Our findings show the potential use of FDG-PET/CT as a screening tool for RCC in this patient population.

Identifying endoplasmic reticulum stress-related genes as new diagnostic and prognostic biomarkers in clear cell renal cell carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) is one of the most common cancers worldwide, and its incidence is increasing every year. Endoplasmic reticulum stress (ERS) caused by protein misfolding has broad and profound effects on the progression and metastasis of various cancers. Accumulating evidence suggests that ERS is closely related to the occurrence and progression of ccRCC. This study aimed to identify ERS-related genes for evaluating the prognosis of ccRCC.

Methods

Transcriptomic expression profiles were obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA), and clinical data were downloaded from the TCGA. First, the differentially expressed genes (DEGs) were analyzed using the limma package, and the DEGs related to ERS (ERS-DEGs) were identified from the GeneCards database. Second, a function and pathway enrichment analysis and a Gene Set Enrichment Analysis (GSEA) were performed. Third, a protein-protein interaction (PPI) network was constructed to identify the hub genes, and a gene-micro RNA (miRNA) network and gene-transcription factor (TF) network were established using the hub genes. Finally, a least absolute shrinkage and selection operator (LASSO) regression analysis was conducted to establish a diagnostic model, and a Cox analysis was used to analyze the correlations between the expression of the characteristic genes and the clinical characteristics.

Results

We identified 11 signature genes and established a diagnostic model. Further, the Cox analysis results revealed a correlation between the expression levels of the signature genes and the clinical characteristics. Ultimately, five signature genes (i.e., TNFSF13B, APOL1, COL5A3, and CDH5) were found to be associated with a poor prognosis.

Conclusions

This study suggests that TNFSF13B, APOL1, COL5A3, and CDH5 may have potential as prognostic biomarkers in ccRCC and may provide new evidence to support targeted therapy in ccRCC.

Complete spontaneous regression of a primary renal cell carcinoma. Report of a pathological proven case and review of the literature

Regression of primary renal cell carcinoma (RCC) is a rare phenomenon and for several reasons many of the reported cases have been questioned. We present a case that can be considered a true spontaneous and complete regression of a primary RCC. A 79-year-old female underwent nephrectomy because a renal tumor. At the time of surgery image studies showed a small para-aortic lymph node. The tumor measured 3cm and was analyzed completely. Histology showed a fibro-inflammatory lesion with necrosis, foamy macrophages and inflammatory cells. No neoplastic cells were observed and the lesion was interpreted as a localized type of xanthogranulomatous pyelonephritis. One year later a CT control scan, showed that the para-aortic lymph node had increased in size to 4cm. Fine needle aspiration revealed features of clear RCC. Metastatic dissemination was limited so surgical removal of the para-aortic lymph node was performed and the cytologic diagnosis confirmed.

Spontaneous Regression of a Pulmonary Metastasis Secondary to Contralateral Metastasectomy

Spontaneous regression is defined as the partial or complete resolution of a malignant neoplasm either with treatment that is perceived to be inadequate or in the absence of therapy. Here, we present the first case of spontaneous regression of a pulmonary metastasis of a renal cell carcinoma secondary to metastasectomy in the contralateral lung.

Desmoid-type fibromatosis of the lower extremity: A unique case of complete lesion resolution following core needle biopsy

Desmoid-type fibromatosis (DF) is a rare neoplasm characterized by fibroblastic and myofibroblastic proliferation. While characterized as a benign lesion that does not metastasize, desmoid-type fibromatosis exhibits a wide range of behavior from aggressive local tissue invasion and post-surgical recurrence to spontaneous regression. Tumor regression can occur following systemic medical therapy or rarely may occur in the absence of therapy. We present a case of a 50-year-old female with a left thigh vastus medialis intramuscular mass which underwent imaging work-up and subsequent core needle ultrasound-guided biopsy showing results of desmoid-type fibromatosis. Following biopsy, the tumor showed prompt, complete regression with complete MRI resolution 2 months following biopsy. The patient showed no evidence of disease recurrence out to one year on MRI surveillance. This case report will discuss desmoid-type fibromatosis imaging features, treatment strategies, spectrum of disease behavior, and atypical behavior such as the spontaneous tumor regression as seen in this case report. To our knowledge there have been no reported cases of DF spontaneous regression 2 months following a core needle biopsy. Understanding the variable behavior of desmoid-type fibromatosis can assist the radiologist in guiding management of these lesions with the goal of optimizing clinical outcomes and preventing unnecessary aggressive treatments for stable or regressing disease.

Checkpoint inhibitor immunotherapy in kidney cancer

Kidney cancer has unique features that make this malignancy attractive for therapeutic approaches that target components of the immune system. Immune checkpoint inhibition is a well-established part of kidney cancer treatment, and rapid advances continue to be made in this field. Initial preclinical studies that elucidated the biology of the programmed cell death 1 (PD-1), programmed cell death 1 ligand 1 (PD-L1) and cytotoxic T lymphocyte antigen 4 (CTLA-4) immune checkpoints led to a series of clinical trials that resulted in regulatory approval of nivolumab and the combination of ipilimumab plus nivolumab for the treatment of advanced renal cell carcinoma. Subsequent data led to approvals of combination strategies of immune checkpoint inhibition plus agents that target the vascular endothelial growth factor receptor and a shift in the current standard of renal cell carcinoma care. However, controversies remain regarding the optimal therapy selection and treatment strategy for individual patients, which might be eventually overcome by current intensive efforts in biomarker research. That work includes evaluation of tumour cell PD-L1 expression, gene expression signatures, CD8⁺ T cell density and others. In the future, further advances in the understanding of immune checkpoint biology might reveal new therapeutic targets beyond PD-1, PD-L1 and CTLA-4, as well as new combination approaches.

The incidence, predictors, and survival of disappearing small renal masses on active surveillance

OBJECTIVE

To evaluate the incidence, predictors, and survival for those small renal masses (SRM, solid mass ≤4 cm suspicious for a clinical T1a renal cell carcinoma) that disappear on imaging while undergoing active surveillance (AS).

SUBJECTS/PATIENTS AND METHODS

The Delayed Intervention and Surveillance for SRM registry prospectively enrolled 739 patients with SRMs. Patients having at least 1 image showing no lesion were considered to have a "disappearing" SRM. Logistic regression assessed predictors of having a disappearing SRM and Kaplan-Meier estimates illustrated relative survival.

RESULTS

Of 374 patients enrolled in AS, 22 (5.9%) experienced a disappearing SRM. Mean time to tumor disappearance was 2.0 years (SD = 1.9) and 50.0% reappeared on subsequent CT imaging. SRM disappearance, most commonly encountered on ultrasound imaging surveillance, was independently associated with tumors <1 cm on multivariable analysis (OR = 10.6 (95% CI: 1.1-100.3), P = 0.04). Furthermore, patients with disappearing SRMs were healthier than other patients on AS with no compromise in overall survival during follow-up (5-year survival = 100% vs. 73.2%, P = 0.06).

CONCLUSIONS

Approximately 5% of SRM on AS will disappear during follow-up on surveillance imaging. Most of these represent artifacts of heterogeneous imaging modalities, including ultrasound, and the SRM will reappear on subsequent imaging. Given the indolent nature of these lesions, disappearance events do not require reflex repeat imaging and patients should continue AS with their original surveillance schedule intact. A smaller percentage of patients undergoing AS for a SRM may have a mass the permanently disappears.

Immune checkpoint inhibitors in renal cell carcinoma

The immune system has long been known to play a critical role in the body's defence against cancer, and there have been multiple attempts to harness it for therapeutic gain. Renal cancer was, historically, one of a small number of tumour types where immune manipulation had been shown to be effective. The current generation of immune checkpoint inhibitors are rapidly entering into routine clinical practice in the management of a number of tumour types, including renal cancer, where one drug, nivolumab, an anti-programmed death-1 (PD-1) monoclonal antibody (mAb), is licensed for patients who have progressed on prior systemic treatment. Ongoing trials aim to maximize the benefits that can be gained from this new class of drug by exploring optimal timing in the natural course of the disease as well as combinations with other checkpoint inhibitors and drugs from different classes.

A rare case of spontaneous necrosis of primary renal cell carcinoma

A 42-year-old woman was referred to our hospital with a chief complaint of asymptomatic gross hematuria. Computed tomography revealed a 4-cm tumour in the left kidney and radical nephrectomy was performed. Microscopically, the tumour was completely necrotic and consisted of nests of cells with abundant cytoplasm and large nuclei. Immunohistochemical analysis indicated complete infarction of the chromophobe renal cell carcinoma. Two years after surgery, the patient remained recurrence-free.

Spontaneous regression of primary renal cell carcinoma following image-guided percutaneous biopsy

Spontaneous regression of metastatic renal cell carcinoma (RCC) is a rare but well-described clinical phenomenon; spontaneous regression of nonmetastatic RCC has been reported far less frequently. We present three cases of primary RCC that regressed spontaneously following the image-guided biopsy that established their diagnosis. We briefly review the literature describing spontaneous regression of both primary and metastatic RCC and emphasize how knowledge of this phenomenon may be useful for abdominal imagers that perform renal biopsy or interpret postbiopsy follow-up studies.

Management of metastatic kidney cancer in the era of personalized medicine

Patients with localized renal cell cancer (RCC) are often cured following surgical resection. However, a significant proportion of patients will experience recurrence or present with metastatic disease at distant sites and may be deemed incurable. The worldwide incidence of RCC is rising, affecting more than 271,000 people and resulting in 116,000 deaths each year. Unfortunately, advanced RCC is typically resistant to classical chemotherapy and radiotherapy. Previously, non-specific immunotherapies such as interleukin-2 and interferon were used in hopes of improving cancer immunity, leading to rare but durable responses. However, enthusiasm for these immunotherapies has waned due to limited patient responses, their excessive toxicities, and the emergence of alternative targeted therapies that have resulted in improved clinical endpoints for patients with metastatic RCC (mRCC). Strides in targeted treatment can be attributed to an improved understanding of the molecular underpinnings that cause and drive the progression of renal cell cancers. More recently, interest in immunotherapies has resurfaced, as agents inhibiting specific checkpoints involved in cancer immune evasion have demonstrated promising activity in patients with mRCC. Here we review the novel targeted agents, biomarkers and immunotherapies that promise to change the clinical outcomes for patients with advanced RCC.