'Cannibalism' (cell phagocytosis) does not differentiate reactive renal tubular cells from urothelial carcinoma cells

Cell-in-cell phenomenon in urinary sediment: a case report

The internalization of apoptotic cells by non-phagocytic cells has been observed in different tissues and could be an important mechanism for the elimination of dying cells. Here, we describe a probable event of phagocytosis of apoptotic cells mediated by urothelial cells in urinary sediment. A 90-years-old male patient was admitted unconscious to the hospital, visible signs included: pale skin and dry mucous membranes, presumptively diagnosed as dehydration. Blood test revealed anaemia (haemoglobin 130 g/L) and hyperglycaemia (glucose 7.8 mmol/L), urinalysis showed a picture of urinary tract infection (leukocyturia and bacteriuria). The microscopic analysis of urinary sediment revealed the presence of urothelial cells and leukocytes internalized in urothelial cells. Anti-CD68 (membrane marker of macrophages) was tested by immunocytochemistry and a negative result was observed. Based on the findings phagocytosis of apoptotic cells mediated by urothelial cells was identified. This phenomenon can be observed in urinary sediment and should not be confused with a neoplastic process since it is a physiological event of cell elimination.

p53 expression in repair/reactive renal tubular cells: A potential pitfall leading to a false-positive diagnosis of urine cytology

Background

p53 immunostaining is routinely used as a surrogate marker for TP53 mutational status. In urine cytology, p53 immunocytochemistry is reportedly useful in detecting urothelial carcinoma cells as well as in improving the detection sensitivity and specificity. However, to the best of our knowledge, p53 expression in repair/reactive renal tubular cells (RRTCs) from urine cytologic specimens has not been assessed to date.

Methods

We evaluated the immunoexpression of p53 and homogentisate 1,2‐dioxygenase (HGD) antibody, a renal tubular cells marker, in RRTCs using voided urine and renal biopsy samples from 80 patients who were histologically diagnosed with glomerular disease.

Results

Repair/reactive renal tubular cells were detected in 68 (68/80, 85%) samples at a mean count of 141.1 cells per sample (range, 5–4220). Immunocytochemical analysis found p53‐positive RRTCs in all the samples (68/68, 100%) with an average p53 positivity rate of RRTCs per sample at 47.7% (range, 3.8%–96.5%). Of the 68 p53‐positive RRTC samples, 38 (55.9%) included cells that were HGD positive for cytoplasm. Similarly, renal biopsy analysis revealed p53‐positive RRTCs in all the specimens (68/68, 100%). All 68 (100%) cases showed RRTCs that were positive for both p53 and HGD.

Conclusion

To avoid false positives of p53 immunocytochemistry, cytologists must consider the fact that RRTCs from patients with glomerular disease are positive for p53.

An insight into the cannibalistic behavior of giant cell granulomas of the jaws

Background:

Cellular cannibalism is defined as a large cell engulfing a smaller one within its cytoplasm. It is predominantly a feature of aggressive malignancies but has recently been demonstrated in giant cell (GC) lesions such as GC tumor of tendon sheath, central GC granuloma (CGCG) and peripheral GC granuloma (PGCG).

Aim:

The aim of the study is to assess the cannibalistic GCs in CGCG and PGCG and correlate with aggressiveness of the lesion.

Settings and Design:

Archival data of histopathologically confirmed cases of CGCG (n = 40) and PGCG (n = 25) were studied in the Department of Oral Pathology, Maulana Azad Institute of Dental Sciences.

Materials and Methods:

Quantification of cannibalistic cells was performed using H&E stain on microscopic sections. One hundred GCs were examined in each slide, and the number of cannibalistic cells was expressed in percentage.

Results:

GC cannibalism was observed in all cases. The mean number of cannibalistic GCs in CGCG was 44.67 which was significantly higher (P = 0.028) than PGCG (mean 28.04). In aggressive (n = 18) CGCG, the mean number of cannibalistic GCs was 51.27 which was significantly higher (P = 0.019) than cannibalistic GCs in nonaggressive (n = 22) CGCG (mean 39.27). No significant difference was observed between the number of cannibalistic cells in recurrent (mean = 52.9) and nonrecurrent (mean = 49.2) cases of CGCG (P > 0.05). Two of the nine cases treated initially by steroid showed fewer and smaller cannibalistic GCs with vesicular nuclei.

Conclusion:

There was a clear distinction in the mean cannibalistic count between aggressive and nonaggressive CGCG. Hence, the aggressiveness of the lesion could be assessed following which appropriate treatment modality can be constituted.

Detecting cell-in-cell structures in human tumor samples by E-cadherin/CD68/CD45 triple staining

Although Cell-in-cell structures (CICs) had been documented in human tumors for decades, it is unclear what types of CICs were formed largely due to low resolution of traditional way such as H&E staining. In this work, we employed immunofluorescent method to stain a panel of human tumor samples simultaneously with antibodies against E-cadherin for Epithelium, CD68 for Macrophage and CD45 for Leukocytes, which we termed as "EML method" based on the cells detected. Detail analysis revealed four types of CICs, with tumor cells or macrophage engulfing tumor cells or leukocytes respectively. Interestingly, tumor cells seem to be dominant over macrophage (93% vs 7%) as the engulfer cells in all CICs detected, whereas the overall amount of internalized tumor cells is comparable to that of internalized CD45+ leukocytes (57% vs 43%). The CICs profiles vary from tumor to tumor, which may indicate different malignant stages and/or inflammatory conditions. Given the potential impacts different types of CICs might have on tumor growth, we therefore recommend EML analysis of tumor samples to clarify the correlation of CICs subtypes with clinical prognosis in future researches.

Is a consistent cytologic diagnosis of low-grade urothelial carcinoma in instrumented urinary tract cytologic specimens possible? A comparison between cytomorphologic features of low-grade urothelial carcinoma and non-neoplastic changes shows extensive overlap, making a reliable diagnosis impossible

INTRODUCTION

The ability to consistently diagnose low-grade urothelial carcinoma (LGUC) in urinary tract cytology (UTCy) specimens remains controversial, as the reported sensitivity of UTCy in the detection of LGUC is as low as 10%. To determine whether a consistent cytologic diagnosis of LGUC is possible, we assessed the presence and frequency of previously described cytomorphologic features of LGUC in UTCy from patients with LGUC and a negative control group.

MATERIALS AND METHODS

Biopsy-proven cases of LGUC from June 1, 2010 to January 31, 2014 were identified; UTCy obtained within 3 months prior to biopsy composed the study group (n = 98). The negative control group consisted of UTCy obtained from patients with negative cystoscopy and biopsy (n = 53). All specimens were masked and reviewed in random order to evaluate 17 cytomorphologic parameters.

RESULTS

Univariate statistical analyses demonstrated that the prevalence of paired cells, clumpy chromatin, and cytoplasmic homogeneity was higher in the study group; however, multivariate analysis did not show these features as significant predictors of LGUC.

CONCLUSIONS

No cytomorphologic feature was statistically significant in the LGUC group versus the negative control group. The presence of 3-dimensional papillary structures with fibrovascular cores is diagnostic of LGUC, but it is only seen in a small minority (2 of 98) cases. Our results reemphasize the fact that urinary tract cytology has a low sensitivity for the diagnosis of LGUC and suggest that, instead of striving to detect LGUC in urine specimens, we should concentrate on the clinically relevant goal of urine cytology-the detection of high-grade lesions.

Androgen receptor (AR) positive vs negative roles in prostate cancer cell deaths including apoptosis, anoikis, entosis, necrosis and autophagic cell death

Androgen/androgen receptor (AR) signaling plays pivotal roles in the prostate development and homeostasis as well as in the progression of prostate cancer (PCa). Androgen deprivation therapy (ADT) with anti-androgens remains as the main treatment for later stage PCa, and it has been shown to effectively suppress PCa growth during the first 12-24 months. However, ADT eventually fails and tumors may re-grow and progress into the castration resistant stage. Recent reports revealed that AR might play complicated and even opposite roles in PCa progression that might depend on cell types and tumor stages. Importantly, AR may influence PCa progression via differential modulation of various cell deaths including apoptosis, anoikis, entosis, necrosis, and autophagic cell deaths. Targeting AR may induce PCa cell apoptosis, autophagic cell deaths and programmed necrosis, yet targeting AR may suppress cell deaths via anoikis and entosis that may potentially lead to increased metastasis. These differential functions of AR in various types of PCa cell death might challenge the current ADT with anti-androgens treatment. Further detailed dissection of molecular mechanisms by which AR modulates different PCa cell deaths will help us to develop a better therapy to battle PCa.

Cell cannibalism and cancer

Cellular cannibalism, defined as a large cell enclosing a slightly smaller one within its cytoplasm. In this review, we discussed the morphology, possible mechanism, and the cytological significance of cannibalism in relation to malignancy. Cannibalism is a completely different entity than phagocytosis, entosis, and emeriopoliosis. It is an important morphologic feature to distinguish benign from malignant lesions. Cannibalism has been described in various cancers such as, bladder cancer, breast cancer, lung cancer, etc, and this is related with the aggressiveness of the malignancy.