Expression of BerEP4 and CD10 IHC Markers in Basal Cell Carcinoma, Squamous Cell Carcinoma and Adnexal Tumours of Follicular Differentiation: A Comparative Study.

Background: Basal cell carcinoma (BCC) is the most common cutaneous malignancy. In most cases, BCC can be diagnosed by its characteristic histopathological features. The differential diagnosis includes basaloid squamous cell carcinoma (SqCC) and adnexal tumours of follicular differentiation. Cluster of differentiation 10 (CD10) and name of an immunostain (BerEP4) are reported to be useful in differentiating between them. Objectives: The primary objective was to compare the expression of BerEP4 and CD10 in BCC with that of SqCC and adnexal tumours of follicular differentiation, and the secondary objective was to evaluate the proportion of different histological subtypes of BCC. Materials and Methods: Twenty-eight cases of BCCs, 34 cases of SqCCs and 16 adnexal tumours of follicular differentiation received in the institution during the study period January 2017 to June 2018 were included in this descriptive study. Immunostaining with CD10 and BerEP4 was performed, and the staining pattern was studied in all 78 cases. A detailed histopathological evaluation including subtyping was carried out for BCC cases. Results: All BCCs showed positivity with CD10 and BerEP4, but the intensity and pattern varied. Squamous cell carcinomas were completely negative for BerEP4 and CD10 in tumour cells, and 25 of 34 cases showed stromal CD10 positivity. Among adnexal tumours of follicular differentiation, proliferating trichilemmal tumour was completely negative for both markers; other adnexal tumours (n = 11/16) showed peritumoral stromal accentuation for CD10, and nine of 11 cases showed BerEP4 tumour cell positivity (P < 0.001). Conclusion: BerEP4 can reliably detect BCCs of all types and distinguish between BCC and SqCC, but it is unable to do so for adnexal tumours such as trichoepithelioma, trichilemmoma and trichoblastoma. CD10 is a useful adjunct marker in distinguishing both trichoepithelioma (TE) and SqCC from BCC. CD10-positive tumour cells favour a diagnosis of BCC and peritumoral stromal accentuation for trichoblastoma (TB) and trichilemmoma (TL). Tumour cells in SqCC are almost always negative for CD10. A combined immunohistochemistry (IHC) panel of CD10 and BerEP4 can serve as a very reliable adjunctive in the diagnosis of BCC.

Spontaneous Change in Density of Colloid Cyst: An Unusual Phenomenon.

BACKGROUND: Colloid cysts of the third ventricle are benign congenital lesions. They are at times totally asymptomatic or may be detected in the evaluation for headache, neurologic disturbances, or psychiatric disturbances. They may sometimes cause grave consequences such as coma or even sudden death. The radiologic appearance is unique and important for making decisions in the management. CASE DESCRIPTION: We report a patient with a colloid cyst who presented to us after sudden deterioration in consciouness. It was noted that he underwent brain computed tomography (CT) scan 10 months ago in the evaluation of headache. Compared with previous CT scan, there was a sudden change in the density and size of the colloid cyst with obstructive hydrocephalus. This unique change in the character of the colloid cyst occurred without any intervention. We discuss the possible etiologies behind this phenomenon along with a review of the literature. CONCLUSIONS: This case stands out remarkably because it is only the second case in literature with similar natural history.

Study of S100 Immunostaining in Demonstrating Neural Granulomas in Paucibacillary Leprosy.

CONTEXT: Neural granulomas are hallmark of leprosy. Challenges faced in diagnosing paucibacillary leprosy include: (i) Difficult visualization of nerve twigs on hematoxylin and eosin (H and E) sections due to their small size and (ii) Paucity of organisms on acid-fast bacilli stain. AIMS: (1) This study aimed to test the role of S100 immunostain in demonstrating neural granulomas in skin biopsies of paucibacillary leprosy, (2) to compare morphology of S100 staining of nerves inside granulomas among clinicohistologically defined different types of leprosy, and (3) to test whether the pattern of S100 immunostaining can distinguish nerve fragmentation/destruction from a normal intact nerve in skin biopsy. MATERIALS AND METHODS: Sixty four diagnosed cases of leprosy were included in this study. Five skin biopsies with no significant pathology (for studying intact nerve) and nine nonleprosy cutaneous granulomas were also studied. RESULTS: (i) In demonstrating neural granuloma, sensitivity of H and E was 48.27% and that of S100 was 100%, (ii) Morphology of nerve fragments on S100 stain for cases of leprosy was fragmented and infiltrated in 37, intact and infiltrated in 19, reduced, fragmented, and infiltrated in seven, and absent in one, (iii) There was a significant difference (P <0.001) in the pattern of staining of S100 on intact nerve and nerves involved by granuloma in leprosy, and (iv) The probability to differentiate between leprosy and nonleprosy granuloma was statistically significant (P <0.001). CONCLUSION: S100 immunostaining showed to be an effective adjuvant to histopathology in diagnosing paucibacillary leprosy and differentiating it from nonleprosy cutaneous granuloma.