Year : 2009 | Volume
: 54 | Issue : 5 | Page : 63--65
Basosquamous carcinoma in an Indian patient with oculocutaneous albinism
Nitin Ranjan1, Satyendra K Singh1, Sayeedul H Arif2,
1 Department of Dermatology, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, India
2 Department of Pathology, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, India
Department of Dermatology, Jawaharlal Nehru Medical College, Aligarh Muslim University (AMU), Aligarh - 202 001, UP
A middle-aged man with type IA OCA presented to us with a large ulcerated plaque of three year duration over the forehead. Histopathology showed basosquamous carcinoma in the form of distinct areas of basal and squamous differentiation. Metastasis workup was negative. Complete surgical excision, strict photoprotection and regular follow-up were advised. A timely recognition of this potentially aggressive neoplasm is the key to curative treatment.
|How to cite this article:|
Ranjan N, Singh SK, Arif SH. Basosquamous carcinoma in an Indian patient with oculocutaneous albinism.Indian J Dermatol 2009;54:63-65
|How to cite this URL:|
Ranjan N, Singh SK, Arif SH. Basosquamous carcinoma in an Indian patient with oculocutaneous albinism. Indian J Dermatol [serial online] 2009 [cited 2021 Oct 19 ];54:63-65
Available from: https://www.e-ijd.org/text.asp?2009/54/5/63/45460
Basosquamous cell carcinoma (BSC) is a rare cutaneous neoplasm with features of both basal (BCC) and squamous cell carcinoma (SCC) which has a potential for aggressive infiltration and destruction. Initially a subject of considerable debate, BSC is now generally accepted to exist as a separate entity, with a reported incidence rate of 1-2% of all carcinomas of the skin.  In Oculocutaneous albinism (OCA), the reduction or complete absence of melanin results in severe photosensitivity and high risk of actinic keratoses, SCC and less commonly, BCC. Here we present a patient with OCA having BSC.
A 52-year-old male, having typical type IA OCA with no apparent pigmentation of the skin, hair and eyes, and greatly decreased visual acuity, nystagmus and photophobia, presented with multiple lesions over sun-exposed areas. His parents were not consanguineous and he had the history of albinism in his two younger brothers. The patient was a farmer and had occupational sun-exposure over the past 30 years with no apparent means of photo-protection. He had developed numerous actinic keratoses in the form of multiple itchy, rough, brownish macules over his face and limbs for the past few years. Three years back, he developed a lesion over the left fronto-temporal aspect of the scalp and the adjoining forehead in the form of a small pea-sized, purple, pigmented lesion, covered with transparent scales and centrally depressed area. The lesion was gradually increasing in size from its onset and at presentation, was an exophytic plaque of size 7´5cm, having a central depressed ulcer with rolled-out edges and focal areas with hemorrhagic crusting [Figure 1]. Widespread telangiectases were also seen over the face. Clinical examination revealed no pallor, cyanosis, icterus or organomegaly. His cervical and axillary lymph nodes were not enlarged.
His hemogram, liver and renal function tests were normal. His chest X-ray and abdominal ultrasonography did not reveal any abnormality. Edge biopsy of the exophytic plaque showed two different types of cells in the tumor tissue. One part of the tumor consisted of large polygonal squamoid cells with occasional keratinization, which we considered as a conventional SCC [Figure 2]. In this area, the tumor cells had abundant eosinophilic cytoplasm, and foci of squamous differentiation in the form of keratin pearls. Another portion of the tumor showed a trabecular growth of basaloid cells (BCC) [Figure 3]. In the basaloid area, the tumor cells were much smaller than the squamoid cells and were hyperchromatic, uniform, and arranged in a peripheral palisading manner. Stromal hyalinization and occasionally heavy melanin pigmentation were prominent in the BCC area. We were not able to perform immunohistochemical studies, due to cost constraints on part of the patient. With a histopathological diagnosis of BSC, extensive surgical excision of the neoplasm has been planned and the patient advised strict photo-protection.
BSC was first described in 1910 by MacCormac  and later by various authors as a tumor having histologic features of both BCC and SCC. Whether BSC exists as a distinct entity or merely represents a collision of 2 neoplasms has been a matter of considerable debate. 
Most authors consider it as a variant of BCC, which differentiates into SCC. While some authors  recommend the exclusion of a collision tumour and a keratinizing BCC before making a diagnosis of BSC, others  list 3 histopathological variants: collision tumors, tumors showing distinct areas of basal and squamous differentiation (as observed in our case), and metatypical carcinomas. In our patient, metatypical carcinoma was ruled out as nowhere did the cells seem to show characteristics between basal and squamous. Keratinizing BCC was ruled out as there was absence of any abrupt keratinization at the center of the BCC tumor nodule. In case of combined or collision tumors, BCC abuts to an adjacently arising SCC. As there were distinct components of BCC and overt SCC in our patient with no abrupt transition between the two tumor types, a collision tumor was also ruled out. In light of the above analysis, distinct areas of basal and squamous differentiation were sufficient to make a histopathological diagnosis of BSC. However, immunohistochemical studies could have aided in further confirmation of the diagnosis.
On the basis of immunohistochemistry, the term basosquamous carcinoma can be applied to tumors resembling BCC that have areas of squamoid differentiation and show positive staining for Ber EP4 ((Epithelial antigen: Clone Ber EP4) with negative staining for EMA (Epithelial membrane antigen: Clone E29).  BSC shows areas of definitive BCC (Ber-EP4+) and SCC (cytokeratin AE1/AE3+) with a transition zone of diminished staining. 
BSCs are more common in men; the face and ears being the commonest sites. However, BSCs have also presented as ulceroproliferative lesions in the vulva.  The clinical morphology of BSCs has ranged from flat, rusty red colored tumors with clinically indistinct borders  to ulcerative cutaneous neoplastic growths causing complete destruction of underlying soft tissue and bone.  BSC is more locally invasive and more likely to recur and metastasize than other forms of BCC [Table 1].  Metastases of BSC are known to occur many years after identification of the primary tumor.  Hence, such patients should undergo regular follow-up as long as possible.
Due to this metastatic potential of BSC, extensive primary surgical resection, possibly completed by radiation or photodynamic adjuvant therapy, are the mandatory therapeutic procedures.  As BSC is more likely to recur after conventional treatment, some authors consider Mohs' micrographic surgery as the most suitable treatment.  However, there is consensus that therapy should be similar to that for SCC, taking into consideration the age and general state of the usually elderly patient. A male gender, large size (>20mm), positive surgical resection margins and lymphatic or perineural invasion are indicators for the aggressiveness of BSC.  The five-year survival rate is estimated to be 17.5%. 
Our patient was having type 1A OCA (Tyrosinase negative OCA), an autosomal recessive disorder caused by mutation of tyrosinase gene on chromosome 11q21, in which absent biosynthesis of melanin pigment in the skin results in severe photosensitivity and high risk of skin cancer.  Such individuals require strict photoprotection and dermatological surveillance. To our knowledge, this is the first case report of an Indian patient with OCA and BSC.
|1||Martin RC 2 nd , Edwards MJ, Cawte TG, Sewell CL, McMastersKM. Basosquamous carcinoma: Analysis of prognostic factors influencing recurrence. Cancer 2000;88:1365-9.|
|2||MacCormac H. The relation of rodent ulcer to squamous cell carcinoma of the skin. Arch Middlesex Hosp 1910;19:172-83.|
|3||Maloney ML. What is basosquamous carcinoma? Dermatol Surg 2000;26:505-6.|
|4||Bianchi L, Bernardi G, Orlandi A, Chimenti S. Basosquamous cell carcinoma with massive cranial osteolysis. Clin Exp Dermatol 2003;28:96-7.|
|5||Beer TW, Shepherd P, Theaker JM. Ber EP4 and epithelial membrane antigen aid distinction of basal cell, squamous cell and basosquamous carcinoma of the skin. Histopathology 2000;37:218-23.|
|6||Jones MS, Helm KF, Maloney ME. The immunohistochemical characteristics of the basosquamous cell carcinoma. Dermatol Surg 1997;23:181-4.|
|7||Yesudian PD, Krishnan SG, Jayaraman M, Janaki VR, YesudianP. Basisquamous carcinoma. Indian J Dermatol 1997;42:123-4.|
|8||Bowman PH, Ratz JL, Knoepp TG, Barnes CJ, Finley EM. Basosquamous carcinoma. Dermatol Surg 2003;29:830-3.|
|9||Farmer ER, Helwig EB. Metastatic basal cell carcinoma: A clinicopathologic study of seventeen cases. Cancer 1980;46:748-57.|
|10||Akdeniz N, Calka O, Metin A, Yuca K, Ozen S. A destructive ulcer. Clin Exp Dermatol 2005;30:731-2.|
|11||Witkop CJ Jr. Inherited disorders of pigmentation. Clin Dermatol 1985;3:70-84.|