A Case of Tubulocystic Carcinoma Simultaneously Occurring with Clear Cell Type Renal Cell Carcinoma and Micropapillary Urothelial Carcinoma of Bladder:

Co‑occurrence of clear cell renal cell carcinoma and bladder urothelial carcinoma: A case report and literature review

The co-occurrence of clear cell renal cell carcinoma (ccRCC) and bladder urothelial carcinoma (bUC) is rare, and owing to the lack of a unified treatment plan, the prognosis is poor. The present report describes the case of a 65-year-old male patient with a history of smoking and no history of malignant tumors who presented with hematuria at the Huanghe Sanmenxia Hospital Affiliated to Henan University of Science and Technology (Sanmenxia, China) in July 2021. Urinary system computed tomography urography revealed a right renal tumor, and cystoscopy revealed intravesical lesions. The patient underwent transurethral resection of a bladder tumor + laparoscopic partial nephrectomy + laparoscopic radical cystectomy and bilateral ureterostomy. Pathological examination revealed right-sided ccRCC (pT1aN0M0) and high-grade invasive bUC (pT2N0M0). After surgery, the patient underwent bilateral ureteral single J tube replacement in the outpatient clinic every 3 months. In September 2022, the patient presented with a mass on the right side of the neck. Further examination revealed a space-occupying lesion in the lower part of the left kidney and space-occupying lesions in the neck, axilla, mediastinal lymph nodes and liver. A neck lymph node puncture biopsy suggested UC, and the patient was diagnosed with metastatic UC (T4N0M1). The patient received tislelizumab (200 mg once every 3 weeks) + sunitinib (50 mg/day, administered for 4 weeks with a 2-week interval) for a total of 2 months and died of an advanced tumor in January 2023. In addition, the data of 36 patients with ccRCC and bUC from the literature were analyzed for the present report. The results showed that the median age at first onset was 56.5 years (range, 31-82 years) and the male-to-female ratio was 6:1. Smoking and male sex may be risk factors for this disease, which has a median survival time of 47.5 months. The survival analysis results showed that the pathological stage of bladder cancer may be associated with its prognosis. The present study reviews the potential risks, clinicopathological characteristics and treatment methods of co-occurrence of clear ccRCC and bUC. In conclusion, the high-risk factors for the co-occurrence of ccRCC and bUC were smoking and male sex, and the median survival time was 47.5 months. The pathological stage of bladder cancer may be related to the prognosis.

Two Unexpected Tumors in a Laparoscopic Nephrectomy Specimen, Including a Rare Tubulocystic Renal-Cell Carcinoma: A Case Report

We present a case of a 52-year-old Caucasian male who underwent a laparoscopic nephrectomy for an atrophic kidney and was found to have two unexpected, synchronous kidney cancers. He had a remote history of testicular cancer complicated by lymphadenopathy and external ureteral compression. Over time, he developed an atrophic left kidney from obstructive uropathy. Years later, due to flank pain and renal scintigraphy showing minimal function, a laparoscopic nephrectomy was performed. Final pathology demonstrated papillary renal-cell carcinoma (RCC) and tubulocystic RCC. Tubulocystic RCC is a rare neoplasm thought to be an indolent subset of collecting duct carcinoma, but was identified as a unique entity in 2004. Currently, there are ∼100 cases of this neoplasm in the literature.

Gains of chromosomes 7 and 17 in tubulocystic carcinoma of kidney: two cases with fluorescence in situ hybridisation analysis

Tubulocystic carcinoma (TCC) is a very rare renal tumour with unique gross and microscopic features, alternatively considered as low-grade collecting duct carcinoma. Recent studies favoured distinction of TCC from collecting duct carcinoma, and some cases of TCC synchronously coexisting with other renal cell tumour subtypes were described. We report here two new cases of pure (case 1) or mixed (case 2) TCC with fluorescence in situ hybridisation (FISH) analysis, which showed gains of chromosomes 7 and 17 in the pure TCC of case 1, as well as in the TCC and the papillary renal cell carcinoma (PRCC) components in case 2. These data may further support the notion that TCC is more closely related to PRCC.

A New Type of Renal Cancer--Tubulocystic Carcinoma of the Kidney: A Review of the Literature

In 2004, A new peculiar subtype of renal cell carcinoma, which later received the name of tubulocystic carcinoma (TCC-RC), was recognized. Though the tumor has distinct macroscopic, microscopic and immunohistochemical features, the tumor was previously considered to have some similarities to various other renal cancers. We did an extensive review of literature using PubMed and CrossRef, which yielded more than 80 cases reported from various parts of the world. We evaluated the epidemiology, tumor presentations, pathological characteristics, treatment, and outcome of TCC-RC.

Synchronous clear cell renal cell carcinoma and tubulocystic carcinoma: genetic evidence of independent ontogenesis and implications of chromosomal imbalances in tumor progression

Seven percent of renal cell carcinoma (RCC) cases are diagnosed as "unclassified" RCC by morphology. Genetic profiling of RCCs helps define renal tumor subtypes, especially in cases where morphologic diagnosis is inconclusive. This report describes a patient with synchronous clear cell RCC (ccRCC) and a tubulocystic renal carcinoma (TCRC) in the same kidney, and discusses the pathologic features and genetic profile of both tumors. A 67 year-old male underwent CT scans for an unrelated medical event. Two incidental renal lesions were found and ultimately removed by radical nephrectomy. The smaller lesion had multiple small cystic spaces lined by hobnail cells with high nuclear grade separated by fibrous stroma. This morphology and the expression of proximal (CD10, AMACR) and distal tubule cell (CK19) markers by immunohistochemistry supported the diagnosis of TCRC. The larger lesion was a typical ccRCC, with Fuhrman's nuclear grade 3 and confined to the kidney. Molecular characterization of both neoplasms using virtual karyotyping was performed to assess relatedness of these tumors. Low grade areas (Fuhrman grade 2) of the ccRCC showed loss of 3p and gains in chromosomes 5 and 7, whereas oncocytic areas displayed additional gain of 2p and loss of 10q; the high grade areas (Fuhrman grade 3) showed several additional imbalances. In contrast, the TCRC demonstrated a distinct profile with gains of chromosomes 8 and 17 and loss of 9. In conclusion, ccRCC and TCRC show distinct genomic copy number profiles and chromosomal imbalances in TCRC might be implicated in the pathogenesis of this tumor. Second, the presence of a ccRCC with varying degrees of differentiation exemplifies the sequence of chromosomal imbalances acquired during tumor progression.

[Tubulocystic carcinoma of the kidney]

A 55-year-old man who presented himself with gross hematuria and right back pain was found to have a right renal mass with evidence of metastasis to the lymph nodes, bone and lung (cT1bN1M1). He underwent a transperitoneal right nephrectomy. Tumor expressed markers of CD10, P504S and CK19 immunohistochemically, so histopathological examination revealed tubulocystic carcinoma of the right kidney (pT3a). After the patient received sunitinib therapy, computed tomography revealed reduction in the size of the metastatic lung nodule and lymph nodes, indicating a partial response. He is alive without disease progression at 12 months after nephrectomy. Tubulocystic carcinoma has been referred to by Amin et al as low-grade collecting duct carcinoma and is not yet included in the World Health Organization (WHO) 2004 classification of renal tumors. The cells lining the tumor range from cuboidal to columnar and have large nuclei with low-grade changes and abundant eosinophilic or amphophilic cytoplasm. Hobnail cells are commonly seen. Immunohistochemically, tubulocystic carcinomas are strongly positive for markers of the proximal nephron (CD10, P504S) and the distal nephron (parvalbumin, CK19). Despite a low nuclear grade, tubulocystic carcinomas occasionally show progressive behavior clinically. Although there is no established salvage therapy, sunitinib was found to be effective for this patient.

Tubulocystic renal carcinoma: a clinical perspective

INTRODUCTION

Tubulocystic renal carcinoma (TCRC) is a recently described neoplastic entity. To date, clinicopathological features on less than hundred cases of these rare tumours have been characterized exclusively in the pathological literature. Herein, we present five additional cases emphasizing clinical aspects on these rare renal neoplasms.

MATERIAL AND METHOD

Cases diagnosed as TCRC were retrieved and reviewed from the routine and consultation files of the Pilsen tumour registry comprising over 20,000 cases of renal tumours.

RESULTS

All patients were men, mean age 56 years (range 29-70). Features on computed tomography (CT) were in two cases Bosniak III, one IV and two were solid tumours. In four patients, nephrectomy was performed, and one patient underwent resection. At the time of surgery, two patients had metastases. In one case, both primary tumour and metastases were active on FDG positron emission tomography (PET)/CT. Both patients with metastatic disease were treated with sunitinib with partial response. One patient died 26 months postoperatively and the other patient is alive 5 months after surgery. Three patients with localized tumours are without evidence of disease 31, 28 and 7 months after surgery. In one case, the resected tumour was histologically combined with a papillary renal cell carcinoma (PRCC).

CONCLUSION

TCRC occurs predominantly in men with a wide age range. TCRC frequently displays a cystic component which may render a radiological classification of Bosniak III or IV. FDG PET/CT is helpful in the detection of metastases. TCRC has definitive malignant potential. Our findings support a possible relationship to PRCC. The tyrosine kinase inhibitor sunitinib may be used a therapeutical agent with partial response and temporary effect.