Squamous Cell Carcinoma In Situ (SCCIS) of the Nipple Following Breast Conserving Therapy: Case Report.

Bowen's Disease of the Nipple in a Woman with Tongue Cancer

Pigmented squamous cell carcinoma in situ with amyloid deposition mimicking melanoma

Although intakes of dietary fat have been associated with both basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin, the evidence is sparse and inconsistent. This study prospectively investigated the association between total dietary fat; saturated, polyunsaturated and monounsaturated fatty acids; and percent energy from fat in relation to BCC and SCC of the skin. At baseline in 1992, total fat intake and intake of fatty acids were assessed in an Australian community-based longitudinal study, using a validated semi-quantitative food frequency questionnaire in 1,057 adult residents (aged 25-75 years) in Nambour, Queensland. Information on demography, sun-sensitivity history and sun exposure factors were obtained using self-administered questionnaires. Associations with BCC and SCC in terms of persons newly affected and of tumor counts were assessed using Poisson and negative binomial regression models, respectively, based on incident, histologically-confirmed tumors occurring between 1992 and 2002. No significant linear trends were observed in overall risk of BCC or SCC of the skin with increasing total fat intake. However, in participants with a history of skin cancer, total fat intake (multivariable adjusted RR = 2.42, 95% CI = 1.20-4.88; p for trend = 0.01) was associated with increased numbers of SCC tumors comparing the highest to lowest tertile. In conclusion, SCC tumor risk increased as total fat intake increased in people with a history of skin cancer. Dietary fats were not associated with BCC occurrence.

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Squamous cell carcinoma: Could it be the most common skin cancer?

Bone Marrow-Derived Cells Are Not the Origin of the Cancer Stem Cells in Ultraviolet-Induced Skin Cancer

Noninvasive squamous lesions are distinctively uncommon in biopsies of the urinary bladder with the exception of nonkeratinizing squamous metaplasia. The clinical significance of these squamous lesions in the bladder remains to be explored. A total of 29 cases of transurethral biopsies and resections of the bladder containing noninvasive squamous lesions (excluding nonkeratinizing metaplasia) were studied from the consult files of one of the authors. These cases included keratinizing squamous metaplasia (5), verrucous squamous hyperplasia (5), squamous papilloma (5), condyloma acuminatum (3), and squamous cell carcinoma in situ (CIS) (11). Immunohistochemistry for epithelial growth factor receptor (EGFR) and in situ hybridization for wide-range human papillomavirus was performed on 23 cases. The follow-up period ranged from 2 months to 3 years with an average of 1.5 years. After the initial diagnoses in biopsies of the bladder, 10 patients received cystectomies, and 7 patients received repeat tissue sampling of the bladder. Of the 5 patients with keratinizing squamous metaplasia, 2 patients had invasive urothelial carcinoma with squamous features in their cystectomy specimens at intervals of 3 and 14 months, respectively, 1 had persistent keratinizing squamous metaplasia on rebiopsy. Of the 5 patients with verrucous squamous hyperplasia, 1 patient had invasive squamous cell carcinoma at cystectomy at an interval of 14 months, 1 had squamous cell CIS on rebiopsy, 1 had persistent verrucous squamous hyperplasia on rebiopsy, and 2 had no evidence of disease at 6 and 24 months. Of the 5 patients with squamous papilloma, 1 patient had low-grade urothelial carcinoma at cystectomy at an interval of 21 months (h/o low-grade urothelial carcinoma preceding papilloma diagnosis), 2 were free of lesions at rebiopsy. Of the 3 patients with condyloma acuminatum, 1 had squamous CIS at cystectomy at an interval of 3 months, 1 had invasive squamous cell carcinoma at 20 months. Of the 11 patients with squamous cell carcinoma in situ (CIS), 3 patients had invasive squamous cell carcinoma at intervals of 2, 3, and 4 months, respectively, 1 had invasive urothelial carcinoma with squamous features in cystectomies at an interval of 12 months, 1 had squamous cell CIS at 10 months, 1 had high-grade urothelial carcinoma (not otherwise specified) at rebiopsy at an interval of 6 months, and 1 had no evidence of disease at 8 months. Among the 9 patients with invasive carcinoma, 4 patients died in the period of 0.5 to 3 years after the diagnoses. Immunohistochemical study with EGFR demonstrated strong signals in 20 cases and no signals in 2 cases. Wide-range human papillomavirus DNA signal was detected in 1 case of condyloma acuminatum and 1 case of squamous cell CIS. Keratinizing squamous metaplasia, verrucous squamous hyperplasia, and condyloma acuminatum in the urinary bladder can be associated with subsequent or concurrent in situ, or invasive squamous carcinoma and should be closely followed. Squamous cell CIS in the urinary bladder is often associated with subsequent or concurrent invasive carcinoma with squamous differentiation. Enhanced expression of EGFR in these bladder squamous lesions suggests that EGFR may represent a logic therapeutic target in those squamous lesions that are difficult to manage clinically.

Seventy-five skin tumours were studied to investigate the value of immunohistochemistry in differentiating basal cell, squamous cell and basosquamous carcinomas of the skin. Archived paraffin-embedded tissue samples of basal cell carcinomas (n = 39), squamous cell carcinomas (n = 23) and basosquamous carcinomas (n = 13) were stained immunohistochemically using a panel of antibodies. All of the basal cell carcinomas stained positively for Ber EP4, in contrast to the group of squamous cell carcinomas, that showed no staining. Basosquamous carcinomas all showed at least some areas of Ber EP4 positivity. None of the basal cell carcinomas, but most of the squamous cell carcinomas (22 of 23) expressed epithelial membrane antigen (EMA). Only one of the basosquamous carcinomas expressed EMA positivity focally. CAM 5.2, carcinoembryonic antigen (CEA) and 34betaE12 antibodies lacked specificity in relation to the different tumour types. Distinction of basal and squamous cell carcinomas of the skin can be readily achieved with routine immunohistochemistry using Ber EP4 and EMA. Identification of basosquamous carcinoma is also facilitated with this method.

Locally advanced skin cancers including squamous cell carcinoma (SCC) of the skin are increasing in incidence. Patients are often elderly with significant comorbidities and therapy can be difficult. New targeted therapies, such as treatment directed at the epidermal growth factor receptor (EGFR), may be effective and less toxic in these patients. However, before designing appropriate clinical trials it is necessary to characterize the expression and activation of targets such as the EGFR to evaluate the rationale of using EGFR inhibitors (EGFRIs) in the treatment of this type of cancer. To characterize the expression and activation by phosphorylation of EGFR in SCC of the skin by quantitative Western blotting using the LiCor immunofluorescence detection system with validation by immunohistochemistry. Secondary objectives were to evaluate downstream targets of EGFR expression and activation in SCC of the skin and to examine the associations between EGFR, pathological features and clinical behaviour of these tumours. Twenty-one mainly locally advanced skin SCCs collected in our institution and stored in our tissue bank over a 4-year period were used for the study. Nine of 21 (43%) tumours expressed EGFR above background. Of those nine, five expressed phosphorylated EGFR. There was no correlation with downstream activation of canonical signalling pathways, pathological features or clinical behaviour. EGFR is expressed in a minority of tumours and then is not always activated. These results show that, before designing a trial with a targeted agent such as an EGFRI in SCC of the skin, it is important to verify the presence of the appropriate target to maximize the best outcome.

There is some evidence that dietary factors may modify the risk of squamous cell carcinoma (SCC) of the skin, but the association between food intake and SCC has not been evaluated prospectively. We examined the association between food intake and SCC incidence among 1,056 randomly selected adults living in an Australian sub-tropical community. Measurement-error corrected estimates of intake in 15 food groups were defined from a validated food frequency questionnaire in 1992. Associations with SCC risk were assessed using Poisson and negative binomial regression to the persons affected and tumour counts, respectively, based on incident, histologically confirmed tumours occurring between 1992 and 2002. After multivariable adjustment, none of the food groups was significantly associated with SCC risk. Stratified analysis in participants with a past history of skin cancer showed a decreased risk of SCC tumours for high intakes of green leafy vegetables (RR = 0.45, 95% CI = 0.22-0.91; p for trend = 0.02) and an increased risk for high intake of unmodified dairy products (RR = 2.53, 95% CI: 1.15-5.54; p for trend = 0.03). Food intake was not associated with SCC risk in persons who had no past history of skin cancer. These findings suggest that consumption of green leafy vegetables may help prevent development of subsequent SCCs of the skin among people with previous skin cancer and that consumption of unmodified dairy products, such as whole milk, cheese and yoghurt, may increase SCC risk in susceptible persons.

In clinical and histopathological practice, it is sometimes difficult to distinguish pseudoepitheliomatous hyperplasia (PEH) from squamous cell carcinoma (SCC) of the skin. Several studies have shown a low density of Langerhans cells in SCC of the skin, and recent research on cervical SCCs has suggested that the decreased density of dendritic cells is secondary to low E-cadherin expression. SCCs of the head and neck similarly have decreased E-cadherin expression, but E-cadherin expression is preserved in PEH. We hypothesized that PEH of the skin would have an increased number of Langerhans cells compared with SCC. We studied immunohistochemical expression of CD1a on paraffin-embedded tissue in 12 cases of SCC and 11 cases of PEH of the skin. The number of Langerhans cells in SCCs vs. PEH was similar; in both types of lesions, the Langerhans cells were decreased in density compared with the normal flanking epidermis. PEH has a decreased number of Langerhans cells compared with the normal epidermis. As SCCs also have decreased numbers of CD1a-positive cells, this stain is not useful in differentiating these two entities.

Patients with squamous cell skin cancer (SCC) have an excellent prognosis but second primary cancers (SPCs) weaken survival prospects. Family history is a known risk factor for cancer but whether it is a risk factor for SPC in patients with SCC is not known. To quantify the risk of family history on SPCs in patients with SCC and estimate survival probabilities of patients with SPCs depending on family history. With 13945 histologically verified SCCs, relative risks (RRs) were estimated for family history using a generalized regression model. For survival analysis, hazard ratios (HRs) were assessed using a multivariable Cox proportional-hazards model. Family history of invasive SCC increased risk of second invasive SCC [RR = 42·92, 95% confidence interval (CI) 33·69-50·32] compared with risk without family history (RR 19·12, 95% CI 17·88-21·08). Family history of any nonskin cancer in invasive SCC increased risk of the same cancers to be diagnosed as SPC (RRFH = 1·48, 95% CI 1·35-1·61 vs. RRno FH = 1·40, 95% CI 1·32-1·48); significant increases were observed for seven different nonskin cancers. Most results were replicated for insitu SCC. SPC was deleterious for survival irrespective of family history; HR for patients with SPC was 4·28 (95% CI 3·83-4·72) vs. those without SPC (1·04). Family history of nonskin cancer was associated with approximately a doubling of risk for SPCs in patients with SCC. SPC increases the death rate in patients with SCC 3-4 times, irrespective of family history. Taking family history into account at SCC diagnosis may help prevention or early detection of SPCs. What's already known about this topic? Second primary cancers (SPCs) are frequently diagnosed in patients with invasive and insitu squamous cell carcinoma (SCC); some epidemiological studies suggest a link to immune dysfunction. Family history of cancer is a risk factor for practically all first primary cancers but whether it also influences risk of SPCs in patients with SCC is not known. The possible influence of family history on survival in patients with SCC remains to be established. Linked Comment:Youlden and Baade. Br J Dermatol 2020; 183:414-415.

Cystic fibrosis transmembrane conductance regulator (CFTR) represents a cAMP-dependent channel found in normal apocrine glands. The classification and histogenesis of extra-mammary Paget's disease (EMPD) remains controversial, but it is generally accepted that primary EMPD exhibits apocrine differentiation. Therefore, we examined the utility of CFTR in the differential diagnosis of EMPD and squamous cell carcinoma in situ (SCCIS). Twenty-five cases of SCCIS and 14 cases of EMPD were evaluated for immunohistochemical expression of CFTR. Expression was scored as 0 (<5% of cells positive), 1+ (5-75% of cells positive) or 2+ (>75% cells positive). Twenty-three of 25 cases of SCCIS showed no reactivity for CFTR, and the remaining 2 cases showed 1+ staining. Thirteen of 14 cases of EMPD showed 2+ staining, while 1 case showed 1+ staining. We recognize that the pathological appearance along with clinical history and site of occurrence are sufficient to distinguish EMPD and SCCIS in most instances. However, distinction between the two can become more challenging when the location and histopathology are not characteristic. We conclude that when an immunohistochemical panel is diagnostically necessary, the expression of CFTR favors a diagnosis of EMPD over SCCIS.

Squamous cell carcinoma in situ (SCCIS) has more subclinical lateral extension than invasive squamous cell carcinomas (SCC). To determine whether it takes a greater number of Mohs stages for clearance of SCCIS compared with SCC and whether the difference in final defect size and clinical size is larger in SCCIS than SCC. All Mohs micrographic surgery cases of SCCIS and SCC performed between January 2011 and December 2021 were identified. Number of Mohs stages were recorded and difference in final defect size and initial clinical size were calculated for SCCIS and SCC. 4,363 cases were included, 1,066 SCCIS and 3,297 invasive SCC. The initial clinical size, final defect size, and the size difference were similar between SCCIS and SCC groups. However, SCCIS underwent more Mohs stages to achieve tumor clearance than invasive SCCs (1.5 ± 0.7 vs 1.4 ± 0.7 respectively, p < .001). In fact, 71% of SCCs were cleared after 1 Mohs stage compared with 61.1% of SCCIS. These findings support that SCCIS has more subclinical lateral extension and therefore is appropriate for Mohs surgery.

Chronic exposure to inorganic arsenic (iAs) elevates reactive oxygen species (ROS) generation and up-regulates TGF-β signalling. This promotes induction of epithelial to mesenchymal transition (EMT) and causes the development of squamous cell carcinoma (SCC) of skin. Black tea is a popular beverage worldwide and an effective antioxidant. Chemopreventive potential of black tea extract (BTE) against iAs induced carcinogenicity has been explored here. The study aims to investigate the role of BTE in prevention of iAs-induced SCC of skin in Swiss albino mice via the modulation of TGF-β signalling and EMT. Mice were divided into (1) control, (2) iAs, (3) iAs+BTE, and (4) BTE groups and were administered iAs and BTE alone, or in combination for 330 days. Histological studies were performed to assess development of SCC. ROS generation was estimated by flowcytometry. Expression of TGF-β and downstream proteins belonging to suppressor of mothers against decapentaplegic (Smad), phosphoinositide-3-kinase (PI3K)-protein kinase B (AKT) and mitogen-activated protein kinase (MAPK) pathways was assessed by immunoblotting. Expression of EMT markers was evaluated by immunoblotting, immunohistochemistry and semi-quantitative reverse transcriptase-PCR. After 330 days of iAs treatment, development of invasive SCC of skin probably due to excess ROS generation, elevation of TGF-β, downregulation of the Smad pathway, upregulation of PI3K-AKT and MAPK signalling molecules and induction of EMT was observed. All these modulations were found to be reversed by BTE, which inhibits iAs induced SCC of skin by quenching excess ROS, promoting Smad mediated TGF-β signalling, downregulating signalling intermediates of PI3K-AKT and MAPK pathways and inhibiting EMT.