Adenoid squamous cell carcinoma of the larynx: an uncommon histological variant of squamous cell carcinoma

Adenoid squamous cell carcinoma (ASCC) or acantholytic squamous cell carcinoma is a well-recognized variant of squamous cell carcinoma. ASCC commonly occurs in the sun-exposed areas of the skin and has only rarely been observed in mucosal sites. We report a case of ASCC in the larynx of a 75-year-old man with a history of odynophagia and dysphonia of 3 months' duration that presented as an exophytic lesion on the right vocal cord. Biopsy was performed and the histological diagnosis was squamous cell carcinoma. Treatment consisted of total laryngectomy and radical neck dissection. Microscopically, the tumor showed a prominent alveolar pattern with cystic degeneration of the neoplastic epithelium and formation of pseudoglandular structures. In the lumina there were acantholytic cells. Transition areas from conventional squamous cell carcinoma to adenoid pattern were found. To the best of our knowledge this is only the third case of ASCC reported in the larynx. We reviewed the nine mucosal ASCCs of the upper aerodigestive tract reported. The assertion that these tumors are associated with an aggressive behavior and poor prognosis cannot be estimated in this review as the number of cases is small and the tumors are located in different places.     

A case report of papillary thyroid carcinoma dedifferentiated to squamous cell carcinoma presenting as a lung metastasis: A potential diagnostic pitfall

Papillary thyroid carcinoma (PTC) tall cell variant (TCV) with squamous dedifferentiation is a rare entity. We present a case of 90‐year‐old woman who initially had a 2.8 cm conventional PTC in right lobe of thyroid who, couple decades later, had metastatic dedifferentiated PTC to right neck lymph nodes level II and IV with tall cell features; to right level IV and V lymph nodes with tall cell and squamous components, which recently presented exclusively as squamous cell carcinoma (SCC) metastasizing to lung. The squamous component in the lymph node and SCC in the lung were both positive for squamous marker p63 and PTC markers TTF1, PAX‐8 and BRAF V600E while negative for thyroglobulin and p16. The papillary component was positive for TTF‐1, BRAF V600E and P63 (majority); negative for thyroglobulin and p16. Final diagnoses were rendered based on combination of cytological features and immunohistochemical profiles. This report highlights the utilization of current biomarkers to distinguish between metastatic dedifferentiated PTC with squamous features and primary lung SCC, as well as the importance of recognizing this rare entity.     

Coexistence of primary squamous cell carcinoma of thyroid with classic papillary thyroid carcinoma

Primary squamous cell carcinoma of the thyroid gland is very rare and its histogenesis is poorly defined so far. Although there have been some cases of squamous cell carcinoma with variant types of papillary thyroid carcinoma (PTC), the present case is the first primary squamous cell carcinoma with classic PTC to be reported. A 43‐year‐old woman presented with a 20 year history of neck mass. Neck ultrasound indicated a 6 × 4 × 3 cm large mass. The patient underwent total thyroidectomy. Histopathology indicated a well‐differentiated squamous cell carcinoma and squamous metaplasia in conjunction with classic PTC. On immunohistochemistry cytokeratin 7 was positive in papillary carcinoma and squamous metaplasia, thyroglobulin was positive only in papillary carcinoma, and p63 was positive in squamous metaplasia and squamous cell carcinoma. Postoperatively, the patient received 59.4 Gy adjuvant radiotherapy, hormonal therapy and radioactive iodine therapy. At 8 months after surgery the patient remained disease free.     

Papillary squamous cell carcinoma of the mandibular gingiva

Papillary squamous cell carcinoma (PSCC) has rarely been reported in the oral cavity. Herein reported is a case of PSCC in the mandibular gum. A 70-year-old man consulted our hospital because of a papillary tumor in the left mandibular gum. Physical examination revealed an exophytic papillary tumor of the left mandibular gum, and an excision of the tumor was performed. Grossly, the tumor was exophytic and papillary, and measured 1 x 1 x 0.8 cm. Microscopically, the tumor showed exophytic papillary proliferation with fibrovascular cores and consisted of atypical squamous epithelial cells. The tumor cells showed hyperchromasia, nuclear atypia, mitotic figures, apoptotic bodies, cancer pearls, and individual keratinization. Mild stromal invasion was seen. Immunohistochemically, the tumor cells were positive for pancytokeratin AE1/3, pancytokeratin CAM5.2, p63, p53, and Ki-67 (labeling index=40%), but negative for human papilloma virus (HPV). HPV in situ hybridization revealed no signals. Therefore, PSCC was diagnosed. The lateral and vertical margins are negative for tumor cell. The pathological diagnosis was PSCC. The patient was healthy and free from tumor three months after the operation.     

Pigmented squamous intraepithelial neoplasia of the esophagus

Squamous cell carcinoma (SCC) usually lacks melanocytes within the tumor. A few reports have documented invasive SCC or SCC in situ (intraepithelial neoplasia, IEN) with melanocytic hyperplasia within the tumor, referred to as pigmented SCC, in some organs. However, case series of pigmented SCC or IEN of the esophagus have not yet been reported. This is the first study to analyze the incidence and clinicopathological features of pigmented SCC or IEN of the esophagus. We reviewed 18 surgically-resected and 122 endoscopically-resected esophageal specimens, including 79 cases of IEN. Three cases of pigmented IEN were observed in this series, and all of them were located in the middle to lower third of the esophagus. Two of 3 cases had melanocytosis in the non-neoplastic squamous epithelium around the IEN. The incidence of pigmented IEN was 2.5% of all endoscopically resected specimens and 3.8% of IEN cases. No pigmented invasive SCC was detected in both endoscopically-resected and surgically-resected specimens. The mechanism of pigmentation of esophageal IEN is unknown. However, production of melanocyte chemotactic factors by tumor cells has been demonstrated in pigmented SCC of the oral mucosa. Moreover, two of 3 cases of pigmented IEN in the present series had melanocytosis in the non-neoplastic squamous epithelium, and melanocytosis is thought to be associated with chronic esophagitis, therefore, it has been hypothesized that various stimuli can cause pigmentation in squamous epithelium. Additional studies are needed to clarify the mechanism of pigmentation in squamous IEN of the esophagus.     

Cytopathology of high‐grade papillary thyroid carcinomas: Tall‐cell variant,diffuse sclerosing variant,and poorly differentiated papillary carcinoma

Cytologic reports of the aggressive tall‐cell and diffuse sclerosing variants of papillary carcinoma have emphasized features such as tall and large cells, increased nuclear size, nuclear pleomorphism, intranuclear pseudoinclusions, three‐dimensional tissue fragments, squamous‐like cells, and dense inflammatory background as characteristic features. However, the specificity of these features in identifying the particular variants and distinguishing them from other poorly differentiated papillary carcinomas and typical low‐grade forms of papillary carcinoma has not been established. The objective of this study was to assess the predictive value of these reported cytologic features. Fourteen cases of high‐grade papillary carcinoma consisting of the aggressive variants (tall‐cell variant (tcv) and diffuse sclerosing variant (dsv)) and poorly differentiated papillary carcinomas (pdpc) were compared to 18 cases of low‐grade papillary carcinoma. Seven cytologic features consisting of the presence of tall and large cells, architectural disorganization, nuclear enlargement, prominent intranuclear pseudoinclusions, nuclear pleomorphism, lymphocytic infiltrate, and squamoid appearance of the neoplastic cells were evaluated. Cytology samples from tcv, dsv, and pdpc consistently demonstrated 3 of the 7 cytologic features (architectural disorganization, nuclear enlargement, and pleomorphism). In contrast, only two of the samples from low‐grade cases demonstrated these 3 features. The recognition of these 3 cytologic features had a positive predictive value of 88% and a negative predictive value of 100% for identifying tcv, dsv, and pdpc. The remaining cytologic features were not a consistent feature in the variants, and by cytology alone, distinction between the aggressive variants (dsv and tcv) and pdpc could not be made. Diagn. Cytopathol. 1999;20:19–23. © 1999 Wiley‐Liss, Inc.     

Papillary and verrucous lesions of the oral mucosa

A wide variety of papillary and verrucous lesions can affect the oral mucosa. Benign and reactive lesions (e.g. squamous papilloma, verruciform xanthoma) usually present little diagnostic difficulty. However, premalignant and malignant verrucous and papillary lesions pose a much greater diagnostic challenge, not helped by often confusing terminology. For example, papillary hyperplasia is a reactive inflammatory condition, whereas the term “verrucous hyperplasia” is often used to describe a potentially malignant lesion, which is probably part of the spectrum of verrucous carcinoma. A classical verrucous carcinoma, with an exo-/endophytic growth pattern and a “pushing” invasive front is easily identified, but many exophytic verrucous proliferations can also show endophytic growth. These can reasonably also be considered as verrucous carcinoma and managed accordingly. The distinction becomes academic in the face of conventional invasion, when squamous cell carcinoma is the appropriate diagnosis. This review aims to summarise and highlight the key features seen in these lesions, and to provide a practical approach for tackling these entities in routine diagnostic practice.     

Rare variants of head and neck squamous cell carcinoma –differential immunohistochemical profiles

We aimed to immunohistochemically characterize the pattern of expression of epithelial markers in rare head and neck squamous cell carcinoma (HNSCC) variants: carcinoma cuniculatum (CC) and adenosquamous carcinoma (ASC). We also present an additional variant of HNSCC with concomitant basaloid and squamous components that has overlapping morphological features with odontogenic and non-odontogenic tumors, which we termed basalo-squamous carcinoma (BSC). The selected markers included CK5/6, p40, CK19, BerEP4, p16 and SOX10. All tumors were CK5/6 and p40 positive. CK19 and BerEP4 were positive in BSC and focally in ASC but negative in CC. p16 was positive in 3 (60%) of the CCs, focally positive in ASC and negative in BSC. SOX10 was negative in all three variants. Our results highlight the plasticity of the lining epithelium revealing differential profiles of immuno-expression of the selected molecular markers, possibly reflecting their diverse histopathogenesis.     

Thyroid carcinoma with papillary and squamous features: Report of a case with histogenetic considerations

We present a case of an 82-year-old female with a painless left latero-cervical swelling, which increased in size over the course of 6 months, compressing adjacent organs. The histopathological examination, following dissection of the left thyroid lobe and ipsilateral cervical lymph nodes, yielded two intermingled morphologically distinct histotypes that included conventional papillary thyroid carcinoma (PTC) and poorly differentiated squamous cell carcinoma (SCC) with cystic features. The clinical presentation, the immunophenotype, and the genotype, especially of the malignant squamous component with partial expression of TTF1, marked expression of p63 and mutation of BRAF, were consistent with the diagnosis of a papillary thyroid carcinoma with squamous component. The possibility of a squamous cell carcinoma of unknown origin metastasizing to a primary papillary thyroid carcinoma cannot be completely ruled out. This particular presentation of thyroid carcinoma carries a poor prognosis in 20% of cases, with high recurrence rates and distant metastasis.     

A rare case of nasal Schneiderian (inverted) papilloma associated with basaloid squamous cell carcinoma

Sinonasal inverted papilloma (IP) is a benign, locally aggressive epithelial neoplasm. In less than 9% of cases it is associated with malignancies, typically conventional squamous cell carcinomas (SCC), while other histological variants have been less frequently reported. We describe the third case of basaloid squamous cell carcinoma (BSCC) arising in nasal IP.An 81-year-old female patient presented with a pinkish irregular lesion on the nasal septum. Biopsy was consistent with IP and carcinoma in situ. Two surgical procedures were needed to obtain radical excision. Histology on the surgical specimen revealed BSCC. Seven months after surgery, there was no evidence of disease recurrence.Although IP is more frequently associated with conventional SCC, other malignancies should be considered. The histological differential diagnosis should be supported by immunohistochemistry. The generally-recommended treatment for sinonasal BSCC is complete surgical resection, although this may be a problem in multifocal distributions, as in the present case.     

Oral variant of acantholytic squamous cell carcinoma—Histochemical and immunohistochemical features

Acantholytic squamous cell carcinoma (ASCC) is an uncommon variant of squamous cell carcinoma (SCC). It is characterized by a combination of typical SCC and pseudoglandular structures, dyskeratotic cells and prominent acantholysis.The purpose of this study was to analyze the histochemical and immunohistochemical characteristics of the intraoral variant of ASCC. Cases of intraoral ASCC were retrieved from the English language literature. Four new cases from our files were added.In total, 35 cases were included and analyzed in this study. The mean age of the patients was 61.5 + 13 years (age range 38–92 years), with a male-to-female ratio of 1.7:1. According to the available data, histochemical and immunohistochemical stains for mucins were found to be consistently negative. E- cadherin, a marker of adherens junctions, was usually reported to be expressed in areas of “typical” (non acantholytic) SCC, but reduced in the acantholytic areas. We examined for the first time the expression of claudin 1, a marker of tight junctions, and found it to be reduced in the acantholytic areas, similar to E-cadherin. Several cases of oral ASCC also expressed vimentin and cytokeratin (CK) 19, markers associated with epithelial-mesenchymal transition. A wide range of non-epithelial markers yielded negative immunoreactions.In conclusion, ASCC is an uncommon variant of squamous cell carcinoma. The acantholytic process appears to involve reduced expression of molecular components of both adherens junctions and tight junctions. These findings could suggest a relation to the epithelial mesenchymal transition process and therefore further studies are needed in order to establish such a link and the subsequent possible impact on the clinical outcome of the patients.     

Vulval squamous cell carcinoma and its precursors

Vulval squamous cell carcinoma (VSCC) can arise through two distinct pathways [human papillomavirus (HPV)-associated and HPV-independent], and these VSCC variants are recognised as different disease entities on the basis of different aetiologies, morphological features, molecular events during oncogenesis, precursor lesions, prognosis, and response to treatment. The precursor of HPV-associated VSCC, variously referred to as high-grade squamous intraepithelial lesion (HSIL) [vulvar intraepithelial neoplasia (VIN) 2/3] or usual-type VIN, is morphologically identical to the more common HSIL (cervical intraepithelial neoplasia 2/3) of the cervix. The precursor lesions of HPV-independent VSCC include differentiated VIN, differentiated exophytic vulvar intraepithelial lesion, and vulvar acanthosis with altered differentiation; these have been under-recognised by pathologists in the past, leading to delays in treatment. This review will discuss the recent advances in diagnostic surgical pathology of VSCC and its precursors, and how these diagnoses can impact on patient management.     

Metastastic variants derived following in vivo tumor progression of an in vitro transformed squamous cell carcinoma line acquire a differential growth advantage requiring tumor-host interaction

The purpose of this study was to develop an experimental model of squamous cell carcinoma that can be used to identify molecular and immunologic changes associated with primary events in malignant transformation, and those associated with metastatic tumor progression in the presence of host homeostatic and immunologic factors. Metastatic variants were derived following in vivo tumor progression of the in vitro transformed squamous cell carcinoma line Pam 212. The parental and metastatic cell lines exhibited similar morphologic features and molecular markers of an epithelial lineage, including an epithelial morphology in culture, cell surface expression of integrin 64, and expression of mRNA of cytokeratins K6 and K14. When the growth and metastatic phenotype of the parental and reisolate cell lines was compared, the reisolate cell lines were found to exhibit a greater rate of growth and incidence of metastasis than the parental cell line when reimplanted in vivo. The difference in the growth rate of the parental cell line and the variants observed in vivo was not detected when growth of these lines was compared in vitro, suggesting that the growth advantage and selection of these variants requires tumor-host interaction. The metastatic variants exhibited a similar growth advantage in normal immunocompetent and SCID Balb/c mice, indicating that the growth advantage in vivo is not due to T or B lymphocyte-dependent immune factor(s). We conclude that metastatic variants derived following in vivo tumor progression of an in vitro transformed squamous cell carcinoma line exhibit a differential growth advantage in vivo that requires the host environment. Comparison of these in vitro transformed and in vivo derived metastatic variant cell lines with phenotypic differences in growth and metastasis should prove useful for dissecting the role of tumor and host factor(s) in malignant transformation and metastatic tumor progression of squamous cell carcinoma.     

Spindle cell tumours of the breast: practical approach to diagnosis

Spindle cell tumours of the breast are uncommon and often present diagnostic challenges. The most important is the sarcomatoid/metaplastic carcinoma, which has monophasic and biphasic variants. Each of these groups presents special diagnostic difficulties. In the monophasic variant the mesenchymal component predominates and the epithelial element forms a minor component often detected only after immunohistochemical study. The spindle cell areas may be bland and therefore under-diagnosed as nodular fasciitis or fibromatosis. Alternatively they may be highly malignant with a pattern that is misinterpreted as primary sarcoma of the breast. In the biphasic variant, the difficulty is in distinguishing between sarcomatoid carcinoma, myoepithelial carcinoma or malignant phyllodes tumour. Other spindle cell lesions of the breast include the various myofibroblastic tumours, the spindle cell variant of adenomyoepithelioma, the varied primary breast sarcomas, metastatic tumours with spindle cell morphology and, finally, the very rare follicular dendritic cell tumour. A simple practical approach to the diagnosis of spindle cell lesions is presented to help the general surgical pathologist to compile a differential diagnosis and to arrive at the correct conclusion     

Multiple brain metastases from a diffuse sclerosing variant of papillary carcinoma of the thyroid

We report a 53-yr-old man who presented with multiple brain metastases from a diffuse sclerosing papillary carcinoma of the thyroid. The presenting clinical features were those of an intracranial space-occupying lesion. Three brain tumors, confirmed pathologically to be metastatic thyroid papillary carcinomas, were removed. Two weeks after craniotomy, total thyroidectomy with cervical lymph node dissection was performed. Both lobes of the thyroid were diffusely enlarged and firm with a dominant mass. Histologically, the tumor was characterized by a combination of bilateral diffuse involvement of the gland, marked fibrosis, squamous metaplasia, abundant psammoma bodies, lymphocytic infiltration, frequent lymphatic and blood vessel permeation of the tumor, and typical elements of a conventional papillary carcinoma. In addition to these histologic findings, elements of other papillary carcinoma variants such as follicular and tall cell variants were also found focally. Twenty-three of twenty-four resected bilateral lymph nodes showed metastases of papillary carcinoma. Although the diffuse sclerosing variant of papillary carcinoma of the thyroid seems to be recognized as an aggressive variant of papillary carcinoma, there is no previous report of brain metastasis from this variant.     

New pathologic entities in penile carcinomas: an update of the 2004 world health organization classification

Most primary malignant tumors of the penis are squamous cell carcinomas (SCC) of the usual type. In recent years several variants, each with distinctive clinicopathologic features, have been described. Pseudohyperplastic carcinoma and carcinoma cuniculatum are both low-grade, extremely well-differentiated SCC variants characterized by an indolent clinical course and good prognosis. The former, which may be confused with pseudoepitheliomatous hyperplasia, preferentially affects the inner foreskin mucosa of elderly men and the latter is a verruciform tumor with an endophytic, burrow-like pattern of growth. Pseudoglandular carcinoma (featuring solid tumor nests with extensive central acantholysis simulating glandular lumina) and clear cell carcinoma (human papillomavirus [HPV]-related tumors composed of periodic acid-Schiff positive clear cells) are aggressive tumors with a high incidence of inguinal nodal metastases. Papillary carcinomas are HPV-unrelated verruciform tumors composed of complex papillae with acanthosis, hyper- and parakeratosis, absence of koilocytes, irregular fibrovascular cores, and jagged tumor base. Finally, in warty-basaloid carcinomas areas of warty (condylomatous) and basaloid carcinomas coexist in the same tumor, either separated or intermingled, giving the tumor a variegated appearance. In this review special emphasis is given to the differential diagnosis of these special variants with a discussion of the possible implications for clinical management.     

Sarcomatoid carcinoma of the urinary tract

Sarcomatoid carcinoma is a rare variant of malignant tumor arising from the urinary tract. This tumor had been termed carcinosarcoma because of its carcinomatous and sarcomatous components. There is still some confusion in the terminology between true carcinosarcoma and sarcomatoid carcinoma; however, the latter is now regarded as primarily a malignant epithelial tumor with pseudosarcomatous transformation.
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended.     

Squamous cell carcinoma of lung associated with osteoclast-like giant cells: report of a case

Resently, we treated a 69-year-old patient with squamous cell carcinoma of lung with osteoclast-like giant cells which were similar with the giant cell tumor of bone. The clinical and pathological characteristics of this case were presented, and the literatures were reviewed. The tumor differed histologically from the pleomorphic carcinoma, which occurs most commonly in the lung and showed diverse pleomorphic manifestation with benign looking osteoclast-like multinucleated cells and bizarre giant cells. In addition, undifferentiated carcinoma with a sarcoma-like appearance containing small areas of papillary adenocarcinoma was evident in the tumor. Histological features and immunohistochemical staining could be helpful in differential diagnosis.