Adenoid Variant of Basal Cell Carcinoma: A Case Report with a Glance at Biological Behavior of the Tumor.

Sir,

Basal cell carcinomas (BCCs) are the most common cutaneous tumors in western literature, accounting for approximately 70% of all malignant diseases of the skin.[1] BCC as a pronounced fact is a tumor which possess a wide morphological and histopathological spectra.[2] Histological diagnosis and classifying BCCs into histological variants not only provide important information regarding low- and high-risk types of the malignancy but also has got a prognostic implication. Thus, reporting histopathological variant of any tumor including BCCs is essential in view of planning patient management.[1]

We report one such case of Adenoid BCC which falls under very rare category of the malignancy.

A 61-year-old female patient presented with a slow-growing brownish-black nodule near the right corner of the mouth since 6 months. The lesion had a pearl white rim surrounding it [Figure 1]. The patient was a farmer with a history of prolonged sun exposure. An excision of the nodule was done under local anesthesia [Figure 2]. Three-month follow-up of the patient revealed the scar tissue [Figure 3]. There was no sign of recurrence of the tumor. Histopathological examination of the H and E-stained section revealed a tumor mass which was chiefly consisting of lobes and lobules of basaloid cells which were in connection to the overlying epidermis [Figure 4a]. The cells were arranged in a typical adenoid and lace-like pattern. The tumor cells showed differentiation in the form of tubular and glandular structures [Figure 4b]. Figure 4c depicts high power view of the same ductular and glandular structures. Retraction spaces were seen around few tumor nests, palisading was noted at the periphery of many nests and islands [Figure 4d]. Thus, the diagnosis of adenoid BCC was given.

Figure 1

A slow-growing nodule near the right corner of the mouth with 1.8 cm in diameter, brownish-black with pearl white translucent rim surrounding it. There was the evidence of foci of erythema along the margin of the tumor

Figure 2

An excision of the nodule was done under local anesthesia

Figure 3

Three months follow-up of the patient revealed the scar tissue

Figure 4

(a) Histopathological examination of the H and E-stained sections revealed a tumor mass which is chiefly consisting of tumor lobes and lobules of basaloid cells which is in connection to the overlying epidermis (×10) (b) the cells were arranged in a typical adenoid and lace-like pattern. The tumor cells show differentiation in the form of tubular and glandular structure (×10) (c) figure depicts high power view of the same ductulara and glandular structures (×40) (d) retraction space was seen around few tumor nests. Palisading was noted at the periphery of many nests and islands. A variable inflammatory infiltrate was present in the section (×40)

The architectural pattern of the tumor cells is a crucial histological prognosticator of tumor determinant. At the same time, the impact of pattern and arrangement of tumor cells on differential diagnosis of the malignancy should also not be underestimated. The above sentence holds true because misinterpretation of a particular cellular pattern can lead to misdiagnosis of the malignancy, as few variants of BCC mimic certain other malignancies which are more aggressive.[3] Adenoid BCC is one such rare, indolent variant of conventional BCC.[4] Exact incidence of adenoid BCC is not known, but Patil et al. reported the incidence of 1.3%.[5]

Establishing the diagnosis of this particular variant of BCC is crucial as adenoid BCC is regarded as a low-grade malignancy. Majority of the cases diagnosed as adenoid BCC have low potential for recurrence and metastasis.[45] Brainard and Hart[6] stated that typical adenoid BCC without admixture features of other aggressive variants of BCC were similar to benign lesions. It did not show propensity to metastasize and in no way was the sole cause of death in patients. Thus, they proposed that designation of the term “malignancy/cancer” which is used to describe this tumor should be changed.[6] The treatment of this is although similar to other BCCs.[456]

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Conflicts of interest

There are no conflicts of interest.