Squamous cell carcinoma arising in a giant epidermal cyst: a case report.

Epidermal cysts are commonly encountered in surgical practice. Malignant degeneration of epidermal sebaceous cyst is uncommon. The authors report the case of a 38-year Filipino woman presenting with a voluminous sebaceous cyst of the left buttock. Ultrasonography and computer tomography were made preoperatively without any hint of eventual malignant degeneration. Marginal excision was performed with direct closure of the skin. The histological examination revealed epidermal sebaceous cyst with squamous cell carcinoma in situ, which is a quite rare, but well known complication occurring in sebaceous cysts.

Mucinous cystadenocarcinoma of the appendix. A rare tumour of the right iliac fossa.

A case of mucinous cystadenocarcinoma of the appendix is presented. The clinical feature is a painful syndrome of the right iliac fossa. In our observation, the diagnosis was not allowed by preoperative imaging. Appendectomy was initially performed and completed by right hemicolectomy and lymphadenectomy after histological diagnosis of the appendicular malignant tumour was forwarded. The prognosis of this tumour is generally excellent providing early diagnosis and wide enough surgery.

Pilomatrix carcinoma.

A 43-year-old man presented with a tumour of the medial part of the right eyebrow. A biopsy was performed and histological examination revealed a malignant transformation of a 'calcifying epithelioma of Malherbe'. A secondary wide excision was performed. Clinical and pathological findings of this extremely rare tumour are reviewed. Factors influencing the prognosis are proposed, based on a compilation of the literature.

Verrucous carcinoma of the nasal septum and columella.

Tumours of the nasal septum are rare. They mostly concern squamous cell carcinomas. Verrucous carcinomas are exceptional, with only three well-documented cases in the literature. We operated such a tumour, localized both on the columella and nasal septum.

Ploidy level and proliferative activity measurements in a series of 407 thyroid tumors or other pathologic conditions.

This study describes the ploidy level and proliferation rate in a series of 74 multinodular goiters (MNGs), 17 cases of Hashimoto's disease, 33 cases of Basedow's disease, 113 adenomas, 139 primary carcinomas, and 31 cervical lymph node metastases from 376 patients. Both ploidy level and proliferation rate were assessed by digital cell image analyses of Feulgen-stained nuclei from formalin-fixed, paraffin-embedded tissues. The ploidy level of each sample was assessed using both its DNA index and its DNA histogram type. The proliferation index assessments corresponded to the determination of the proportion of cells in the S-phase fraction. The data reveal that the proportion of aneuploid cases increases according to the following sequence: simple MNGs and normomacrovesicular adenomas-->MNGs with adenomatous hyperplasia and microvesicular adenomas and Hürthle cell adenomas-->papillary and Hürthle cell carcinomas-->follicular and medullary carcinomas-->anaplastic carcinomas. This suggests the preneoplastic nature of the microvesicular adenomas and even of MNGs with adenomatous hyperplasia. The ploidy levels of 99% of the 407 cases of the thyroid tumor series could be described using six DNA histogram types: diploid, hyperdiploid, triploid, hypertriploid, tetraploid, and polymorphic. It was possible to assess the proliferation rate of 279 samples. The results show that a significantly higher proportion of malignant compared with benign thyroid tumors (35.5% v 10.5%, respectively) exhibited a proliferation index higher than 5%, and that, whether benign or malignant, the hypertriploid thyroid tumors proliferated significantly less than the nonhypertriploid thyroid tumors.

Hypertrophic osteoarthropathy and thyroid cancer.

We describe a case of aggressive undifferentiated thyroid cancer associated with rapidly evolving hypertrophic osteoarthropathy (HOA) that developed at the time of pulmonary dissemination of the thyroid neoplasm. The syndrome appeared to be paraneoplastic, possibly due to a substance normally cleared by the lungs.

Quantitative nuclear cell image analyses of thyroid tumors from archival material.

Sixty-three sections of Feulgen-stained thyroid cell nuclei from paraffin-embedded material, including five multinodular goiters, 10 adenomas, 36 papillary carcinomas, seven follicular carcinomas, and five medullary carcinomas were analyzed by means of the SAMBA 200 (TITN, Grenoble, France) cell image processor. This was done in order to obtain nuclear characteristics of papillary versus follicular carcinomas. The nuclear features were assessed by morphometric, densitometric, and textural parameters. Our preliminary results indicate that the cell nuclei from typical histopathologic specimens of follicular thyroid cancers belong to a larger thyroid cell nuclei population corresponding to the histopathologic family of papillary thyroid cancers. This follicular neoplastic cell nuclei population appears to be quite distinct from the typical medullary neoplastic cell nuclei population which also belongs to the papillary neoplastic cell nuclei population. It appears that there is a specific papillary cell nuclei subpopulation containing typical hypochromatic cell nuclei. We also observed a dramatic increase in nuclear size and hyperchromatism between normal (multinodular goiters) and neoplastic (carcinomas) thyroid tissues, with the benign tissues (adenomas) showing intermediate nuclear characteristics.