Basaloid squamous carcinoma of the oral cavity: report of 2 cases and study of AgNOR, PCNA, p53, and MMP expression

Case Report: Basaloid Squamous Cell Carcinoma of the Tongue: A Case Report

The upper aerodigestive tract is where basaloid squamous cell carcinoma (BSCC), a rare variation of conventional SCC, is most frequently found. The hypopharynx, tonsil, supraglottic larynx, tongue (base), and head-neck regions are particularly susceptible to BSCC. Clinically, the presentation of BSCC is similar to that of conventional SCC, but it has a poorer prognosis than conventional SCC. BSCC is distinguished histopathologically by a dimorphic pattern, a distinctive basal cell component paired with a squamous component, and a squamous component. However, its similar features to conventional SCC make it difficult to diagnose. Therefore, histopathology and immunohistochemistry play a crucial role in diagnosing such tumors. Here we present the case of a 70-year-old male diagnosed with BSCC involving the tongue.

Histopathological Characterization of a Series of Oral Basaloid Squamous Cell Carcinoma

Basaloid squamous cell carcinoma (BSCC) is a rare, distinctive, and aggressive variant of squamous cell carcinoma (SCC) primarily seen in the upper aerodigestive tract with epiglottis, soft palate, and base of the tongue being site of high preference in head and neck region. It differs from conventional SCC histologically and immunologically, is most frequently found in males in their sixth and seventh decades, and is frequently linked to alcohol and tobacco use. High stage disease with distant metastases, a high recurrence rate, and a dismal prognosis is how BSCC typically manifests. In the present article, we report four cases of BSCC.

Recent Advances in Nano-Bio-Sensing Fabrication Technology for the Detection of Oral Cancer

Nanotechnology-based miniaturized devices have been a breakthrough in the pre-clinical and clinical research areas, e.g. drug delivery, personalized medicine. They have revolutionized the discovery and development of biomarker-based diagnostic devices for detection of various diseases such as tuberculosis, malaria and cancer. Nanomaterials (NMs) hold tremendous diagnostic potential due to their high surface-to-volume ratio and quantum confinement phenomenon, improving the detection limit of clinically relevant biomolecules in bio-fluids. Thus, they are helpful in the translation of bench-on platform to point-of-care (POC) screening device. The nanomaterial-based biosensor fabrication technology has also simplified and improved oral cancer (OC) or oral squamous cell carcinomas (OSCC) diagnosis. The fabrication of nano-bio sensors involves application specific modifications of NMs. The unique properties functionalized NMs have augmented their application on the nano-biosensing platform for the detection of clinically relevant biomolecules in bio-fluids. Therefore, this article summarizes the recent advancements in the process of fabrication of nano-biosensors for detection of OC.

Differential expression of claudin‑4, occludin, SOX2 and proliferating cell nuclear antigen between basaloid squamous cell carcinoma and squamous cell carcinoma

Basaloid squamous cell carcinomas (BSCCs) in oral lesions are extremely rare, and the histology is not well understood. Histologically, they are often similar to conventional squamous cell carcinoma (SCC). The present study was designed with an aim to distinguish BSCC from SCC using claudin‑4, occludin, SRY‑box 2 (SOX2) and proliferating cell nuclear antigen (PCNA) immunoreactivities and staining patterns. Three BSCCs (with abundant, with moderate, and without squamous components) specimens and 20 SCC specimens were selected for comparison of their immunoreactivity. These specimens were stained with claudin‑4, occludin, SOX2 and PCNA. In addition to histological analysis, the expression of claudin‑4, occludin and PCNA was determined in oral cancer HSC2 and HSC3 cells with or without SOX2 overexpression, and cell proliferation was determined by XTT assay. Claudin‑4 had strong and occludin had weak immunoreactivity as detected in the membrane of squamous components of BSCC but not in cancer cells. No obvious detection of squamous components and cancer cells were observed in SCC. SOX2 and PCNA immunoreactivities in SCC had dot‑like staining patterns in the nuclei of partial and marginal cancer cells. In contrast, in BSCCs, SOX2 and PCNA had diffuse staining patterns in almost all cancer cells. SOX2 overexpression had little effect on the expression levels of claudin‑4, occludin and PCNA. It also had little effect on the cell proliferation of HSC2 and HSC3 cells. Differences in immunoreactivity and staining pattern may be valuable to distinguish between BSCC and SCC in diagnosis.

A Rare Case of Stage IV Basaloid Squamous Cell Cancer with Intrapulmonary and Brain Metastases

BACKGROUND Metastatic basaloid squamous cell carcinoma is a fatal, high-grade variant of squamous cell carcinoma that is extremely rare in the oral cavity. We present a rare case of metastatic basaloid squamous cell carcinoma arising from the hypopharynx with pulmonary and brain metastases. Recognizing this diagnostic subtype is of critical importance due to the aggressive nature and high incidence of recurrence, lymph node metastases, and mortality. CASE REPORT A 42-year-old male arrived at the Emergency Department reporting a 1-week headache. Six months prior, he reported throat pain and neck swelling. Triple endoscopy revealed a large ulcerative tumor. A carbon dioxide laser procedure debulked and removed the mass. Incisional biopsy with histopathology was consistent with invasive basaloid squamous cell carcinoma. Computed tomography (CT) of the neck with contrast demonstrated bilateral cervical level II/III necrotic adenopathy, and CT chest with contrast demonstrated bilateral pulmonary nodules. The patient completed chemoradiation therapy with cisplatin; however, repeat CT chest revealed enlarging intrapulmonary metastases. CT brain without contrast demonstrated a central brainstem lesion. The patient started treatment with pembrolizumab. On day 14 of treatment, he presented to the Emergency Department again for headache. MRI of brain with contrast demonstrated a new lesion with vasogenic edema. Intravenous dexamethasone was started and the decision to pursue stereotactic radiosurgery was made. CONCLUSIONS The diagnosis of basaloid squamous cell carcinoma in the setting of intrapulmonary and brain metastases is an extremely rare, high-grade bimorphic aggressive variant of squamous cell carcinoma that needs to be histopathologically differentiated from other tumors. Given its high mortality rate and poor prognosis the decision to pursue further treatment versus aggressive palliative care should be discussed.

Basaloid squamous cell carcinoma - A rare and aggressive variant of squamous cell carcinoma: A case report and review of literature

Basaloid squamous cell carcinoma (BSCC) is a rare and aggressive variant of oral squamous cell carcinoma with a predilection for the tongue and in other locations, such as floor of the mouth, palate, retromolar trigone, and gingival mucosa. Here, we present a case of BSCC of oropharynx in a 60-year-old male patient.

Potential impact of human papilloma virus on survival of basaloid squamous carcinoma of the head and neck

OBJECTIVES

Basaloid-squamous-carcinomas (BSCC) have been considered as aggressive variants of common squamous-cell-carcinomas (HNSCC). Recent studies demonstrated a different clinical course depending on the tumour site. The aim of the study is to analyze the histopathologic/clinical features of BSCC/HNSCC resolved by the HPV-status.

METHODS

We analysed the histopathologic/clinical features of BSCC (n=59) and HNSCC (n=981), subdivided due to the HPV status. Differences were analysed using Chi square, Fisher exact, and student's t-test. Survival rates were calculated by Kaplan-Meier and log-rank test. Prognostic variables were subsequently evaluated by Cox regression.

RESULTS

Our cohort was congruent with the literature regarding sex, age, metastases, and a predilection in the oropharynx. HNSCC/BSCC did not show a different disease-specific-survival. After UICC matching, univariate analysis revealed a better survival of UICC stage IVa BSCC compared to HNSCC (69% vs. 42%, p=0.022) that was associated with a better response to radio-chemotherapy (p = 0.009). These results referred to the high prevalence of HPV+ (86%) oropharyngeal BSCC. Subgroup analysis demonstrated a better survival of HPV+ oropharyngeal BSCC than HPV- BSCC (p=0.017).

CONCLUSION

The clinical outcome in BSCC depends on the tumour site and HPV-status. Prospective studies have to evaluate the beneficial application of postoperative radio-chemotherapy in HPV+ BSCC.

Expression of E-cadherin and β-catenin in basaloid and conventional squamous cell carcinoma of the oral cavity: are potential prognostic markers?

Background

Basaloid squamous cell carcinoma presents with a preference for the head and neck region, and shows a distinct aggressive behavior, with frequent local recurrences, regional and distant metastasis. The alterations in the cadherin-catenin complex are fundamental requirements for the metastasis process, and this is the first study to evaluate the immunostaining of E-cadherin and β-catenin in oral basaloid squamous cell carcinoma.

Methods

Seventeen cases of this tumor located exclusively in the mouth were compared to 26 cases of poorly differentiated squamous cell carcinoma and 28 cases of well to moderately differentiated squamous cell carcinoma matched by stage and tumor site. The immunostaining of E-cadherin and β-catenin were evaluated in the three groups and compared to their clinicopathological features and prognosis.

Results

For groups poorly differentiated squamous cell carcinoma and basaloid squamous cell carcinoma, reduction or absence of E-cadherin staining was observed in more than 80.0% of carcinomas, and it was statistically significant compared to well to moderately differentiated squamous cell carcinoma (p = .019). A strong expression of β-catenin was observed in 26.9% and 20.8% of well to moderately differentiated squamous cell carcinoma and poorly differentiated squamous cell carcinoma, respectively, and in 41.2% of basaloid squamous cell carcinoma. The 5-year and 10-year overall and disease-free survival rates demonstrated no significant differences among all three groups.

Conclusions

The clinical and biological behavior of three groups of the oral cavity tumors evaluated are similar. E-cadherin and β-catenin immunostaining showed no prognostic value for basaloid and conventional squamous cell carcinomas.

Basaloid squamous cell carcinoma of retromolar trigone: A case report with review of literature

Basaloid squamous cell carcinoma (BSCC) is a rare distinct histologic variant of squamous - cell carcinoma of the head and neck region. BSCC is more aggressive and has a poorer prognosis, although histologically, it is associated with squamous cell carcinoma and squamous atypia. The usual site of occurrence for BSCC is the upper aerodigestive tract, floor of the mouth and base of the tongue. This is a case report of an unusual case of BSCC of retromolar trigone, which is quite rare.

Basaloid squamous cell carcinoma of the tonsil: report of a case and review of the literature

The most common type of malignancy affecting the upper aerodigestive tract is squamous cell carcinoma. Basaloid squamous cell carcinoma (BSCC) is a rarely seen, high-grade, bimorphic variant of squamous cell carcinoma, which displays distinct histological features. This entity was first described by Wain et al. in 1986. Since then, approximately 170 cases of head and neck basaloid squamous cell carcinoma have been reported. Tonsils are an uncommon site of occurrence of basaloid cell carcinoma. Only 10 cases of basaloid squamous cell carcinoma arising in the tonsils have been described in current English literature. Histopathologically, these carcinomas are characterised by the presence of a basaloid component in close association with squamous cell carcinoma. In this article, a case of BSCC of the tonsil is reported. The clinical and histopathological features of this tumour are discussed. Relevant literature has been reviewed and differential diagnosis of this tumour is discussed.

Basaloid squamous cell carcinoma of the head and neck: report of 18 cases

Objective:

To evaluate the clinical course and pathological characteristics of basaloid head and neck squamous cell carcinoma.

Method:

Retrospective study of 18 cases of basaloid head and neck squamous cell carcinoma. Epidemiological, clinical and histological data were analysed and the Kaplan–Meier test used to estimate survival rates.

Results:

The majority of lesions were at an advanced stage. These lesions were primarily localised in the larynx, hypopharynx and oropharynx. Routine pre-therapeutic assessment of squamous cell carcinoma was performed. Pathological diagnosis was difficult, although immunostaining was extremely useful. Positive staining for KL1, MNF 116 and 34βE12 and negative immunostaining for chromogranin and synaptophysin were also important factors in obtaining a definitive diagnosis. In the majority of cases, treatment involved surgery and radiotherapy. The five-year survival rate was 5 per cent.

Conclusion:

Basaloid squamous cell carcinoma is an uncommon head and neck lesion, with a challenging histological diagnosis. These lesions must be carefully monitored due to their aggressive course, and require multimodality treatment.

Basaloid squamous carcinoma of mandible

Basaloid squamous carcinoma is a rare distinct histologic variant of squamous cell carcinoma of the head and neck region. Basaloid squamous carcinoma is more aggressive and has a poorer prognosis, although histologically, it is associated with squamous cell carcinoma and squamous atypia. The usual site of occurrence for basaloid squamous carcinoma is the base of the tongue, hypopharynx (pyriform sinus), and the supraglottic larynx (Wain et al. Hum Pathol 1986;17:1158-1166). We are reporting an unusual case of basaloid squmous carcinoma of the mandible with no secondaries and features of sarcomatoid pattern histologically.

Expression of PCNA and Bcl-2 in Basaloid Squamous Cell Carcinoma of the Larynx: A Controlled Study

We investigated the difference in the biologic nature of typical squamous cell carcinoma (SCC) and basaloid SCC (BSCC) of the larynx by studying proliferation and antiapoptotic markers. We performed an immunohistochemical analysis of the expression of proliferating cell nuclear antigen (PCNA) and bcl-2 protein in 15 patients with laryngeal BSCC and 15 stage-and site-matched controls with typical laryngeal SCC. We found no significant difference between the two groups in the PCNA index or the frequency of bcl-2 overexpression, nor did we find any significant difference in survival. Our findings indicate that the biologic nature of typical laryngeal SCC and laryngeal BSCC is similar. In addition, our follow-up data suggest that the clinical course of laryngeal BSCC is no worse than that of typical laryngeal SCC.

Basaloid squamous cell carcinoma of the soft palate: case report

Basaloid squamous cell carcinoma (BSCC) is a histologically distinct variant of squamous cell carcinoma. It occurs in various sites of the head and neck region and is believed to carry a dismal prognosis. The palate is a very rare site of BSCC development and only three cases have been reported in the international literature. In this report, we present a case of basaloid squamous cell carcinoma of the soft palate. The therapeutic strategy and histological findings are described in detail, including immunohistochemistry with the use of involucrin, an agent used for the first time for BSCC diagnosis. In addition, a brief review of the literature is presented.

Computer-assisted analysis of cell proliferation markers in oral lesions

Abnormalities in any component of the cell cycle regulatory machine may result in oral cancer, and markers of cell proliferation have been used to determine the prognosis of tumor progression. The aim of this study was to determine whether silver-stained nucleolar organizer region (AgNOR) and Ki-67 measurements could improve the assessment of growth rates in oral lesions. Eighty-three oral biopsies were studied, 20 of which were classified as fibrous inflammatory hyperplasia (FIH), 40 as leukoplakia (LKP) and 23 as oral squamous cell carcinoma (OSCC). Within the LKP group, 22 out of 29 biopsies were diagnosed as non-dysplastic leukoplakia (LK) and 18 as dysplastic leukoplakia (DLK), presenting discrete, moderate and severe dysplasia. Ki-67 immunolabeling of the lesions increased steadily in the following order: FIH, DLK, LK and OSCC, indicating that Ki-67 is a good marker for predicting the proliferative fraction among benign, premalignant and malignant oral lesions. The median values of AgNOR parameters indicate that the morphometric index gives better results regarding the proliferative rate than the numerical one. A series of linear regressions between AgNOR parameters and Ki-67 showed positive associations. We conclude that a combination of Ki-67 and morphometric AgNOR analyses could be used as an aid in the determination of the proliferative status of oral epithelial cells in oral cancer.

Spindle basaloid squamous carcinoma of the upper aerodigestive tract: immunohistochemical and clinicopathological study of three cases

We describe the clinicopathological and immunohistochemical features of three spindle (sarcomatoid) basaloid squamous carcinomas in three men aged 73, 69, and 59 years with a history of tobacco and alcohol abuse. Two tumors were located in the hypopharynx and one was located in the nasal cavity. The three tumors have a pedunculated polypoid appearance. Histologically, they were composed of conventional basaloid squamous carcinomas with extensive malignant spindle cell proliferation, comprising more than 50% of the tumor. The sarcomatoid component demonstrated immunoreactivity with one or more epithelial markers. One case in addition expressed CD99 and Bcl-2 and was originally diagnosed as monophasic synovial sarcoma; however, a subsequent biopsy disclosed basaloid squamous cell carcinoma with sarcomatoid stroma. Two patients were treated with surgery and radiation whereas one refused therapy. The patients were alive 14 (case patient 1), 10 (case patient 2), and 8 (case patient 3) months after diagnosis. In the absence of evidence from immunohistochemical or electron microscopy studies, a polypoid malignant spindle cell tumor of a mucosal surface of the upper aerodigestive tract should be considered a sarcomatoid carcinoma until proven otherwise. The type of epithelial component would determine the subtype of sarcomatoid carcinoma.

Increased expression of matrix metalloproteinase-2 and 9 and human papilloma virus infection are associated with malignant transformation of sinonasal inverted papilloma

BACKGROUND AND OBJECTIVES

In this study, we identified matrix metalloproteinase (MMP)-2 and 9 expression in exophytic papilloma (EP), inverted papilloma (IP) with dysplasia, IP with carcinoma, and invasive squamous cell carcinoma (SCC). We also compared the presence of MMP-2 and 9 with human papilloma virus (HPV) infection.

METHODS

The nasal tissue were stained with monoclonal antibodies to MMP-2 and 9. The results were analyzed using quantitative immunohistochemical analysis. In situ hybridization studies for HPV DNA for 6/11, 16/18, and 31/33 were also performed on the tissue.

RESULTS

Significant increase of MMP-2 and 9 were observed in IP with moderate and severe dysplasia, IP with carcinoma, and invasive SCC compared to control nasal mucosa. Among IP, HPV 6/11-positive was present in 41% and HPV 16/18-positive was present in 31%. In HPV 6/11 and 16/18-positive IP, significant increase of MMP-2 and 9 were observed.

CONCLUSIONS

Precancerous lesions of IP exhibited elevated levels of MMP-2 and 9 and these expression may be associated with early events in IP carcinogenesis. HPV infection would be an early event in a multistep process of malignant formation of IP.

Expression of PCNA, p53, Bax, and Bcl-X in oral poorly differentiated and basaloid squamous cell carcinoma: Relationships with prognosis

BACKGROUND

The aim of this study was to compare the clinical features and proliferating cell nuclear antigen (PCNA), p53, Bcl-X, and Bax expression in primary oral basaloid squamous cell carcinoma (BSCC) and poorly differentiated squamous cell carcinoma (PDSCC) matched by stage and site and to assess the possible prognostic significance of these variables.

METHODS

Seventeen cases of oral BSCC were compared with 27 PDSCCs matched by stage and tumor site. In addition, PCNA, p53, Bax, and Bcl-X expression in both carcinomas were evaluated in relation to their clinicopathologic features and prognostic values using the Kaplan-Meier method and Cox regression models.

RESULTS

No statistically significant differences were found between the groups (BSCC and PDSCC) in regard to clinical features and immunohistochemical reactivity for antibodies PCNA, p53, and Bcl-X. In comparison with PDSCC, the BSCC group exhibited a higher Bax score (p = .031). The 5-year and 10-year overall survival, cancer-specific survival, and disease-free survival rates demonstrated no significant differences between the BSCC and PDSCC groups, and the PCNA, p53, Bax, and Bcl-X also showed no prognostic value.

CONCLUSIONS

These results suggest that the clinical and biologic course of BSCC is similar to PDSCC in the oral cavity when clinical stage and site are matched.

Basaloid Squamous Cell Carcinoma of the Larynx: A Report of Four New Cases

OBJECTIVES

This study is designed to report the clinical and pathologic features and outcome of cases of basaloid squamous cell carcinoma (BSCC) of the larynx treated in our clinic.

STUDY DESIGN

A retrospective review of the medical records of these patients.

METHODS

Four cases of BSCC of the larynx were treated in our department. Histopathologic slides were reevaluated to confirm the diagnosis. Immunohistochemical studies were performed, and file records were reviewed. Follow-up was available for all patients and ranged between 11 and 72 (mean 37) months.

RESULTS

All patients were male (mean 57), with supraglottic or transglottic larynx tumors. Two patients presented with stage-II disease and the other 2 with stage-IV disease. Initial diagnosis was invasive squamous cell carcinoma in 3 patients and BSCC in one patient. Two patients who had stage-II disease underwent partial laryngectomy and bilateral neck dissections; total laryngectomy and bilateral neck dissections were performed in stage-IV patients. Three patients received adjuvant postoperative radiotherapy, and 2 of them also received additional chemotherapy. Patients with stage-IV disease were found to have 4 and 27 metastatic lymph nodes on histopathologic examination and died because of distant metastases at 11 and 14 months, respectively. Patients with stage-II disease did not have cervical metastasis on histopathologic examination and were alive and free of disease at 52 and 72 months respectively.

CONCLUSION

In contrast with the literature reporting the tendency of more aggressive clinical behavior of the BSCC, we can say that BSCC has a behavior similar to conventional squamous cell carcinoma based on our 4 cases.

Basaloid squamous cell carcinoma of the head and neck

PURPOSE OF REVIEW

Basaloid squamous cell carcinoma is an uncommon variant of squamous cell carcinoma and was first described as a distinct entity in 1986. Basaloid squamous cell carcinoma seems to have a poorer survival rate than classical squamous cell carcinoma. On the basis of a critical literature survey, we attempt to evaluate if basaloid squamous cell carcinoma is really more aggressive and presents a poorer outcome than squamous cell carcinoma.

RECENT FINDINGS

All papers are retrospective, and most include small numbers of cases, which are further diminished when subdivided according to specific sites. Only in three studies was basaloid squamous cell carcinoma of the head and neck region compared with matched squamous cell carcinoma controls. These studies did not show a uniform tendency regarding the aggressiveness and outcome of basaloid squamous cell carcinoma. In addition, several recent papers confirmed the presumed greater aggressiveness and worse outcome, and other recent papers questioned these characteristics.

SUMMARY

The presented literature survey does not permit conclusions regarding the aggressiveness and outcome of basaloid squamous cell carcinoma compared with squamous cell carcinoma. Greater numbers of basaloid squamous cell carcinoma should be studied and compared with site-matched, stage-matched, and age-matched controls of conventional squamous cell carcinoma.

Basaloid in contrast to nonbasaloid head and neck squamous cell carcinomas display aberrations especially in cell cycle control genes

BACKGROUND

At present, the differences between head and neck basaloid squamous cell carcinoma (BSCC) and nonbasaloid squamous cell carcinoma (SCC) are mostly on the basis of histologic and immunohistologic findings.

METHODS

In this study, we investigated 8 BSCCs and 59 SCCs for loss of heterozygosity (LOH) at chromosomes 5q, 9p, 9q, 10q, 11q, 13p, 17p, and 18q. In addition, we analyzed p16, PTEN, and CCND1 (cyclin D1) and investigated the HPV status. Immunohistochemically, the expression of MIB-1, p16, p53, and cyclin D1 was determined.

RESULTS

Aberrations in the BSCCs were especially frequent at 9p and in the CCND1 gene. In contrast, alterations at 10q occurred almost exclusively in conventional SCCs. Obvious differences could be determined concerning the HPV status: HPV-DNA was detected in all BSCCs but only in 17% of conventional SCCs.

CONCLUSIONS

Although the number of investigated BSCCs is rather low and did not allow statistical conclusions, our results focus on certain differences between the molecular pathogenesis of BSCCs and SCCs.

Sebaceous adenoma of oral cavity: report of case and comparative proliferation study with sebaceous gland hyperplasia and Fordyce's granules

Sebaceous adenoma (SA) is a rare solitary tumour with a predilection for the forehead and scalp. In the English literature, less than 10 cases of SA have been described in the oral cavity. The objective of this study was to examine the clinicopathologic features and evaluate the expression of epidermal growth factor and its receptor, estrogen receptor and androgen receptor in SA and in its differential diagnoses including sebaceous gland hyperplasia (SGH) and Fordyce's granules (FG). Additionally, we analysed the proliferative potential of sebaceous cells from SA, SGH and FG by measuring proliferating cell nuclear antigen (PCNA) expression and quantification of argyrophilic nuclear organizer regions (AgNORs). The SA showed many clinicopathologic similarities to cases previously reported including the biphasic population of cells, in the periphery of lobules undifferentiated basaloid cells whereas the central area was formed by mature sebocytes. SA was composed of 198 lobules of sebaceous cells, whereas SGH and FG showed a mean of 21 +/- 7.81 and 5.84 +/- 2.83, respectively. The AgNOR and PCNA indices were similar in SA, SGH and FG. These data suggest that lobule counts may be used as additional criteria in distinguishing SA of the oral cavity from other intraoral sebaceous gland lesions.

Basosquamous carcinoma

BACKGROUND

Basosquamous carcinoma (BSC) is a rare cutaneous tumor that has been poorly described in the dermatologic literature. It has been depicted as an aggressive tumor with a high incidence of distant metastasis.

OBJECTIVE

To examine the average extent of local tissue invasion and presence of distant metastases in cases of BSC compared with those of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC).

METHODS

One thousand consecutive Mohs surgery cases performed between January 1993 and May 1995 at the Oschner Clinic in New Orleans, Louisiana, for histologically confirmed BCC, SCC, and BSC were reviewed. Each case was retrospectively evaluated for tumor type, anatomic location, number of Mohs stages performed, and presence of metastases at the time of surgery, as determined by chest radiograph.

RESULTS

Seven hundred forty-five BCCs, 228 SCCs, and 27 BSCs (1,000 tumors total) were treated in 580 patients. The average number of stages required for clear margins in cases of BCC, SCC, and BSC was 1.62, 1.51, and 2.00, respectively. The prevalence of metastasis was 0.87% for SCC and 7.4% for BSC, which was statistically significant (P<0.001).

CONCLUSION

In this retrospective study, BSCs displayed tissue invasion similar to that of BCC or SCC but had a higher frequency of pulmonary metastasis than SCC.