Squamous cell carcinoma of the skin: dual differentiations to rare basosquamous and spindle cell variants

Basosquamous carcinoma (BSC) is defined as a tumor containing the areas of both basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) with a transition zone linking the two. Spindle cell squamous carcinoma (SCSC) may have a variable component of conventional SCC and spindle cells. We present a case of an 89-year-old woman with an eruption on the scalp for several decades. Grossly, the lesion measured 8.5 x 6.0 x 1.8 cm and consisted of a gray-white and focally black tumor. Microscopically, a non-ulcerated upper part of the tumor consisted of large polygonal squamoid cells with occasional keratinization (SCC), trabecular growth of basaloid cells with peripheral palisading (BCC), and an area in which both the components were intermingled. The rest of the tumor was a myxoid area with elongated fusiform spindle cells, which appeared to arise from conventional SCC. Immunohistochemically, the tumor cells in the SCSC (both conventional and spindle cell) area co-expressed CAM5.2, and vimentin. Ber-EP4 was positive in the BCC area with the transition zone of SCC and BCC showing diminished staining. Epithelial membrane antigen was focally positive in the conventional SCC area. To our knowledge, this is the first case report of SCC of the skin that has dual differentiations to BSC and SCSC.     

Rippled-pattern basal cell carcinoma

Basal cell carcinoma (BCC) is the most common malignant cutaneous neoplasm, however, there have been few studies on BCC with a "rippled pattern" so far. We reviewed the 650 BCC specimens from the archives of our institution, and only one example of BCC with a rippled pattern was found. We herein report the histopathological characteristics of this case. Within the lesion, which showed the typical histopathological features of nodular BCC, there was a noticeable area composed of 10-15 basaloid aggregations, which showed the rippled pattern. The rippled pattern was characterized by alternating bands of epithelial cords of spindle-shaped basaloid cells and mucinous spaces. Characteristically, around the rippled-pattern area, neoplastic aggregations with a mucinous reticulated or cystic pattern (pseudo-tubular structures), and many cord-like structures were seen. A review of the published work and the present case suggested that the histopathological characteristics of rippled-pattern BCC are: (i) a nodular type of BCC; (ii) considerably rare; (iii) have frequent intervention by mucinous spaces between the epithelial cords; and (iv) no apparent divergent differentiation with folliculosebaceous-apocrine lineage. The last three characteristics contrasted with those of the rippled-pattern sebaceoma/trichoblastoma. However, neoplastic germinative cells in rippled-pattern BCC may naturally form cord-like structures in a manner similar to rippled-pattern sebaceoma/trichoblastoma.     

Basal cell carcinomas in association with basaloid follicular hamartoma

We describe a unique case of various types of basal cell carcinoma (BCC) associated with basaloid follicular hamartoma (BFH) in a 56-year-old female patient. The lesion consisted of a dark brown and elastic soft nodule and papules within the area of a birthmark on the neck. The lesion was surgically excised. Histological examination of the nodular region revealed aggregations of neoplastic basaloid cells. We diagnosed the nodule as BCC with a racemiform or reticular pattern. In addition, a specimen taken from brownish black papules within the birthmark was found to be composed of anastomosing cords of basaloid cells accompanied by infundibular cystic structures. These features were consistent with an infundibulocystic BCC. In contrast, specimens from a hamartomatous plaque showed distinctive branching strands of basaloid cells that are suggestive of BFH. Therefore, our findings indicate that several types of BCC may develop within a BFH.     

Monster cells in malignant melanoma

Cells with significantly enlarged nuclei have been described in basal cell carcinomas, dermatofibromas, and pleomorphic fibromas, to name a few. These cells are typically visible using low power microscopy and have been termed "pleomorphic" or "monster cells." They have not been previously described in cutaneous melanomas. We sought to determine the prevalence of monster cells in otherwise conventional biopsies of primary cutaneous melanomas and its association with other histopathologic features of this malignancy. Ninety-nine superficial spreading melanomas, nodular melanomas, and acral lentiginous melanomas/lentigo malignas were retrospectively evaluated for the presence of monster cells, multinucleated giant cells, ulceration, inflammation, and depth of invasion (Breslow level). Thirteen cases of melanoma containing monster cells were found. A statistically significant association was noted between the presence of these cells, the histologic subtype of nodular melanoma (P = 0.0125), ulceration (P = 0.0127), the depth of invasion (P = 0.0103), and the presence of multinucleated giant cells (P = 0.0016). The finding of monster cells is not an uncommon occurrence and is seen more often in nodular melanomas.     

Basal cell carcinoma with matrical differentiation.

Three cases of basal cell carcinoma showing shadow cells within basaloid islands have been described using the term basal cell carcinoma with matrical differentiation for this histologic variant. We present four new cases of basal cell carcinoma with evidence of matrical differentiation. Unlike the cases previously published, these lesions showed nests of shadow cells either within the lobules of basaloid cells or forming nests in the stroma. We also noted the presence of a foreign body reaction and calcification. These neoplasms illustrate the capability of basal cell carcinoma to differentiate toward hair matrix cells. Basal cell carcinoma with matrical differentiation must be added to the uncommon variants of basal cell carcinoma showing adnexal differentiation. A parallel between the degrees of differentiation of the cutaneous sebaceous neoplasms with those showing matrical differentiation is proposed.     

Basal cell carcinoma with monster cells

A case of basal cell carcinoma with "monster cells" is reported. Clinically, the lesion presented as a red nodule on the forearm of a 58-year-old male. The histologic picture was striking, with large, "monstrous" nuclei scattered throughout a well defined nodule. Basal cell carcinoma with monster cells appears to represent a histologic variant of nodular basal cell carcinoma. The prognostic significance of the monster cells remains to be established.     

Ber-EP4 and MNF-116 in a previously undescribed morphologic pattern of granular basal cell carcinoma.

Granular basal cell carcinoma (GBCC) is a rare subtype of basal cell carcinoma (BCC) with only seven previously described cases in the literature. A 65-year-old man presented with a papule on his cheek that was subsequently removed. Histopathologic examination revealed that the neoplasm had no connection to the overlying epidermis and that the neoplasm had two different morphologies; nodules composed solely of granular cells and other nodules with a rim of basaloid cells and central granular cells. The neoplasm stained for both Ber-EPF4 and MNF-116 thus confirming it as a subtype of BCC. GBCC should be considered in the differential diagnosis of nodular neoplasms containing granular cells.     

Caveats in BerEP4 staining to differentiate basal and squamous cell carcinoma

Background: Superficial skin biopsies of basal cell carcinoma (BCC) represent some of the most common dermatopathology specimens. Superficial shave biopsies containing partial samples of lesions with squamatization present difficulties in distinguishing BCC from squamous cell carcinoma (SCC). BerEP4 has been employed as a dependable marker in differentiating between BCCs and SCCs.
Methods: We collected 12 cases of superficial biopsies of BCC with centrally located cords and strands suggesting squamous differentiation at the Yale Dermatopathology Laboratory over a 3-month period and stained them with BerEP4.
Results: We found that all cases (12 out of 12) showed membranous and cytoplasmic staining with BerEP4 in the obvious areas of basaloid differentiation at the periphery of the tumors, while cords and strands of enlarged cells with squamoid features in the center and surface of the biopsy failed to label with BerEP4.
Conclusions: BerEP4 labeling is not reliable in superficial biopsies of BCC with squamoid features. It is important to be aware of this caveat in interpreting BerEP4 staining for BCC and SCC.     

Proliferation patterns reflect architectural dedifferentiation: a study of nodular basal cell carcinoma

The distribution of proliferating cells in basal cell carcinoma (BCC) may be related to lesion type and architecture. Single proliferation indexes may not be representative. We aimed to establish the distribution of cell proliferation in BCC as related to architecture. We studied an unselected, consecutive series of 45 resection specimens of nodular BCC from patients in the age range of 25-95 years using MIB-1 staining and systematically reviewed the cases. These lesions included nodular (n=32) and non-nodular (n=9) BCC. Within the nodular BCC, two patterns were recognised, not related to age or gender. In small nodular patterns with well developed peripheral palisading and central parallel streaming of small, elongated nuclei, proliferation is limited to the basal palisading cells in a clustered distribution. In large nodular patterns, proliferation is absent at the basal membrane (BM) and distributed in single random cells throughout the lesion. Both patterns preclude accurate quantitation. Many lesions contained both patterns in a side-by-side, unmixed manner. These pattern differences suggest a loss of differentiation in nodular BCC. Perhaps a single mutation results in the loss of BM associated cell architecture and proliferation control related to tumor-stroma interactions. As a result, the lesion reverts to a low frequency, non-regulated proliferation, diffusely distributed throughout the lesion. The two patterns may exist side-by-side in a single lesion, further supporting the concept of polyclonality. This hypothesis explains perilesional clefting and previously reported variations in intra-lesional laminin synthesis. Based on our findings, representation of tumor cell proliferation activity by a single value is not justified. Nodular BCC exists in one of two dedifferentiation-mutation-determined patterns of cell proliferation; many lesions clearly demonstrate bi-clonality.     

Basal cell carcinoma with sebaceous differentiation

Some authors have used sebaceous epithelioma as a synonym for basal cell carcinoma (BCC) with sebaceous differentiation. However, our review of the literature revealed that definite cases of BCC with sebaceous differentiation that provide adequate clinical and histopathologic information are scarce. We present the case of a 72-year-old woman with a pigmented nodular lesion on her right ala nasi region, clinically diagnosed as pigmented BCC. Histopathologically, this nodular lesion, which was completely excised, showed typical features of BCC. It was noteworthy that within one aggregation of the presented BCC, tiny and small duct-like structures lined by cornified layers with a crenulated inner surface were seen. Vacuolated cells were scattered within a few aggregations, and they had foamy, bubbly cytoplasm and starry nuclei. The vacuolated cells were immunohistochemically positive for epithelial membrane antigen (EMA). These histopathologic findings demonstrated unquestionable sebaceous differentiation in this BCC, namely BCC with sebaceous differentiation, which should be distinguishable from both sebaceoma and sebaceous carcinoma. The small duct-like structures lined by eosinophilic cuticle, indicating apocrine differentiation, were also observed in this BCC.     

Multiple lesions of granular cell basal cell carcinoma: a case report

Granular cell change in basal cell carcinoma (BCC) occurs rarely. Only 11 such cases have been reported; all of them were solitary nodular BCC. We report herein a case of multiple granular cell BCC with infundibulocystic features. The tumors presented as papules on the anterior neck of a 44‐year‐old female with a prior history of a well‐differentiated squamous cell carcinoma (SCC) of the tongue and radiation involving the area in which BCC developed. Microscopically, the tumors were circumscribed small dermal nodules composed of epithelial cords with granular eosinophilic cytoplasm and entrapped infundibular keratocysts. Given the eosinophilic appearance of the tumor, history of SCC and the lesions multiplicity, the initial biopsy was first interpreted as metastatic SCC. The correct diagnosis of granular cell BCC was established upon rereview of the slides at a cancer center. Given the diagnostic controversy, immunohistochemical stains were performed. The tumor cells expressed Ber‐EP4, CD63 (NKI/C3) and CD68. The tumors were compared to the prior SCC finding different morphologies. Extensive clinical evaluation showed no evidence of recurrent SCC. This report expands the clinicopathologic spectrum of granular cell variant of BCC and documents for the first time eruption of multiple such tumors in a localized area.     

A case of sarcomatoid carcinoma of the skin

We describe the histological and immunocytochemical findings of an exophytic cutaneous tumour with mixed features of atypical fibroxanthoma (AFX) and basal cell carcinoma (BCC). A 73-year-old woman presented with a rapidly growing tumour measuring 35 mm in diameter and 10 mm in height on the left forearm. The tumour was excised and histology revealed a biphasic tumour with a pleomorphic spindle cell component and an associated tumour composed of discrete islands of atypical basaloid cells with peripheral palisading consistent with BCC. The two tumours merged into each other at one point. The spindle cell tumour showed a positive immunocytochemical reaction to fibrohistiocytic marker of KP-1 (CD68) and a negative immunocytochemical reaction to AE1/AE3, CAM5.2, S-100 and HMB-45, features consistent with AFX. Immunocytochemistry of the basaloid tumour showed a positive reaction to epithelial markers AE1/AE3 and CAM5.2, and a negative reaction to S-100, HMB-45 and KP-1 (CD68). To date, 15 cases of primary cutaneous carcinosarcoma have been reported in the literature. It has been postulated that these tumours may originate from undifferentiated progenitor cells capable of producing multiple cell lines.     

Fascin-1蛋白在基底细胞癌及鳞状细胞癌中的表达

目的 探讨fascin-1蛋白与基底细胞癌及鳞状细胞癌局部侵袭的相关性。方法 免疫组化方法对10例正常皮肤组织、13例皮肤基底细胞癌（8例结节型、5例浅表型）、24例皮肤鳞状细胞癌（11例原位鳞状细胞癌,13例侵袭性鳞状细胞癌均无转移）进行fascin-1染色,计算机图像分析系统进行观察及定量分析。结果 Fascin-1蛋白在原位鳞状细胞癌（平均光密度0.1152 ± 0.04574）、侵袭性鳞状细胞癌（平均光密度0.1257 ± 0.03096）中的表达明显高于正常上皮组织（平均光密度0.0293 ± 0.00981,P ＜ 0.05）。在结节型基底细胞癌（平均光密度0.0808 ± 0.05642）、浅表型基底细胞癌（平均光密度0.0806 ± 0.04346）中表达差异无统计学意义,但明显高于正常上皮组织（平均光密度0.0293 ± 0.00981,P ＜ 0.05）。结论 在基底细胞癌及鳞状细胞癌中,fascin-1蛋白表达上调可能与肿瘤的局部侵袭相关。     

皮肤鳞状细胞癌和基底细胞癌癌细胞表达CD54抗原的免疫电镜研究

为探讨皮肤鳞状细胞癌（鳞癌）和基底细胞癌（基癌）癌细胞上是否低水平表达CD54抗原,应用低温聚合、包埋后染色的胶体金免疫电镜技术,对3例鳞癌和3例基癌CD54免疫组化色阴性的癌细胞进行了研究。在3例鳞癌和3例基癌中,各2例癌细胞表面及突起处观察到CD54胶体金颗粒的存在;其中1例鳞癌张力微丝－桥粒复合体处还可见CD54胶体金颗粒分CD54抗原。该结果可解释皮肤鳞癌和基癌临床上可发生转移,但发生率较低的机理,值得进一步研究。     

Medusa head-like granules in squamous cell carcinoma with differentiation toward a hair follicle structure

A case of squamous cell carcinoma (SCC) with regional lymph node metastasis in a 69-year-old Japanese man is reported. The tumor was characterized by the proliferation of peripheral basaloid, inner squamoid, and glycogen-rich cells, the presence of trichilemmal keratinization, and the presence of ladder-like, membrane-coating granules. These findings suggested that this tumor differentiates toward a hair-follicle structure. The most interesting feature of this tumor was the presence of medusa head-like granules in the cytoplasm of the clear squamoid cells adjacent to the keratinized cells. We have been unable to find any other studies of these granules in squamous cell carcinoma.     

皮肤基底细胞癌和皮肤鳞状细胞癌270例回顾性分析

 目的:总结我院皮肤基底细胞癌(BCC)和皮肤鳞状细胞癌(SCC)临床与组织病理资料,以期提高BCC与SCC的诊断率。方法：回顾性分析2014年1月1日-2018年12月31日间我院皮肤科门诊经组织病理切片确诊的170例BCC与100例SCC患者的临床与病理资料。结果：BCC与SCC年度发病整体均呈逐渐上升趋势。BCC、SCC男女患病比例分别为0.8∶1、1∶1，好发部位均为曝光部位(头面颈部和四肢)，临床诊断与组织病理诊断符合率分别为62.4%与30.0%。临床诊断上，BCC易与脂溢性角化病(SK)、色素痣混淆；SCC易与BCC、鲍温病、光线性角化病(AK)混淆。结论：BCC和SCC为临床常见的非黑素性皮肤肿瘤，但易误诊和漏诊。临床医生对于可疑病灶应尽早行皮损组织病理检查。     

An unusual apocrine carcinoma on the forehead

We herein report an unusual case of apocrine carcinoma on the forehead. The lesion was formed by the anastomosis of numerous tubular structures with widespread decapitation secretion, thus demonstrating apocrine differentiation. However, we observed some unusual histopathologic features that differed from those found in typical examples of apocrine ductal carcinoma, namely: 1) a relatively well-circumscribed lesion in the dermis, and 2) nodular or solid aggregations composed of basaloid cells. We believe the present case is an apocrine ductal carcinoma, although it has a nodular appearance and basaloid cells. Otherwise, it could be a hitherto undescribed variant of apocrine carcinoma. This apocrine carcinoma on the forehead may have originated from either pluripotential cells or from apocrine glands at an unusual site.     

SGK1在日光性角化病、基底细胞癌及鳞状细胞癌中的表达

目的：检测SGK1在日光性角化病（AK）、基底细胞癌（BCC）及鳞状细胞癌（SCC）中的表达。方法：采用免疫组化SABC法检测SGK1在25例正常皮肤(NS)、25例AK、28例BCC、28例皮肤鳞状细胞癌标本中的表达。结果：NS、AK、BCC和SCC标本中,SGK1阳性细胞率分别为（40.03±14.42）%,（36.63±14.28）%,（52.82±18.73）%和（52.58±20.13）%。BCC组和SCC组分别与NS组比较,差异均有统计学意义（Ps<0.05）。各组SGK1染色阳性细胞率>50%的标本分别为6例（24%）,3例（12%）,16例（57.14%）和14例（50%）,BCC组和SCC组分别与NS组比较,差异均有统计学意义（Ps<0.05）。结论：SGK1的高表达可能与基底细胞癌及鳞状细胞癌的发病有关。