International Journal of Surgical Pathology

5-Fluorouracil (5-FU) represents the basis of chemotherapy for colorectal carcinoma, inhibiting thymidylate synthase (TS), an essential enzyme for DNA replication. Previous studies have associated high TS protein expression by tumor cells with poor outcome of patients with colorectal carcinoma, but others have refuted these findings. In view of the potential role of TS as predictive parameter and the lack of consensus in the literature, the present study compared 2 methods: protein expression and gene polymorphism, correlating them with clinicopathological findings. Immunohistochemical detection of TS in tumor cells and detection of gene polymorphism in the blood were performed in 32 patients with colorectal carcinoma treated with 5-FU. No correlation was found between TS protein expression and gene polymorphism. Neither method correlated with survival, tumor staging, and tumor histological grading. This result possibly reflects a complex tumor response to 5-FU therapy, where TS is just one of the involved proteins.

RET/PTC rearrangements are initiating events in the development of a significant proportion of papillary thyroid carcinomas. Activated RET/PTC mutations are thought to be restricted to thyroid disease, but this study proposes that these events may also occur in nonthyroid tumors. A total of 57 nonthyroid papillary tumors were examined for RET/PTC rearrangements using interphase fluorescence in situ hybridization, Taqman reverse transcriptase polymerase chain reaction, and immunohistochemistry. Taqman single nucleotide polymorphism detection was used to analyze for expression of mutated BRAF T1799A. In all, 20% (3/15) of primary peritoneal carcinoma had detectable RET/PTC1 rearrangements by all 3 methodologies. A further case of similar histotype had an alternate RET/ PTC rearrangement. No RET/PTC1 rearrangements were detected in the remaining tumor cohort. All 57 tumors were homozygous for wild-type BRAF. The results indicate that RET/PTC rearrangements occur in a small subset of nonthyroid papillary tumors. These rearrangements may not be directly implicated in tumor growth; rather representing “passenger” mutations reflecting RET instability in secondary tumor subclones.

This study investigates the potential clinical significance of c-erbB-2 gene and chromosome 17 alterations by fluorescence in situ hybridization (FISH) analysis and HER2/neu overexpression by immunohistochemical staining in transitional cell carcinoma (TCC) of urinary bladder correlating the results with tumor stage and grade categories and with clinical behavior. Sixty-three cases of TCC retrieved from the files of 2 institutions were analyzed for chromosome 17 aberrations and c-erbB-2 amplification by FISH analysis and evaluated immunohistochemically for HER2/neu overexpression. Five tumors were G1, 29 intermediate grade (G2), and 29 tumors high grade (G3); 32 tumors had stage Ta, 18 tumors T1, and 13 tumors T2. We found polysomy of chromosome 17 in 58.7% of TCC with average chromosome copy number >2.26; increased number of HER2/neu gene copy was observed in 66.7% of tumors. C-erbB-2 amplification occurred in 6.3% of tumors. Immunohistochemically, 60.3% of TCC overexpressed HER2/neu and 39.7% of tumors were negative. All tumors with polysomy showed simultaneously increase of HER2/neu gene copy number of which 34/37 with protein overexpression. A statistically significant correlation between polysomy of chromosome 17 and tumor stage (P = .0003) and tumor grade (P < .0001) was found; polysomy was not seen in G1 tumors; however, 8/29 G2 tumors and 29/29 G3 tumors revealed polysomy of chromosome 17; in 8/32 Ta tumors, 14/18 T1 and 13/13 of deeply invasive tumors (T2) polysomy 17 was observed. Moreover, it was found that 7 superficial tumors (1 Ta and 6 T1) showed high polysomy with average of chromosome 17 copy number ≥3.76 as observed in all invasive tumors. The data suggest that although HER2/neu amplification, found in high grade and invasive tumors, is a rare event in TCC, polysomy of chromosome 17 is an important factor correlated with tumor stage and grade categories and could be considered a molecular marker of tumor progression with interesting diagnostic implications.

The classification of lung cancer has always been primarily based on the morphologic assessment of routinely stained histological sections, but this approach may be difficult or even unfeasible in cytological preparations or small biopsies. Moreover, the simplistic dichotomization between small-cell carcinoma and non-small cell carcinoma (NSCLC) should be overcome, as new drugs have been discovered that are effective in specific subtypes of lung cancer. A more accurate characterization of NSCLC, however, may be hard in carcinomas lacking clear-cut signs of differentiation. The incorporation into the diagnostic algorithm of poorly differentiated carcinomas of an immunohistochemical panel including markers of squamous (high-molecular-weight cytokeratins, p63) and glandular (TTF-1, cytokeratin 7) cell differentiation seems the most promising approach. The evaluation of lung cancer for gene mutations, gene amplification, tumor-related angiogenesis, expression levels of DNA repair genes and genomic or proteomic profiles represents an exciting challenge for the pathologist in the near future.

The pathologist is frequently involved in the diagnostic approach to the patient with suspected sarcoidosis. Although the histologic diagnosis is generally not difficult, atypical and underrecognized features may occasionally occur and may result in diagnostic problems. The authors review the histology of pulmonary sarcoidosis, focusing particularly on these unusual problematic findings.

Diverticulosis of the appendix is a relatively rare pathological finding. The majority are acquired pseudodiverticula. True congenital diverticula are very rare. Appendiceal diverticulosis is usually an incidental finding and clinically asymptomatic. When symptomatic, it is usually complicated by acute or chronic diverticulitis with or without acute appendicitis. It presents with atypical abdominal signs and symptoms, mostly in adult males. Appendiceal diverticulitis is a distinct entity with several clinical and pathological differences from acute appendicitis. It has a more rapid progression to perforation and a higher rate of mortality. Therefore, appendiceal diverticulitis should be considered in the clinical differential diagnosis, especially in adult males with chronic abdominal pain. Appendiceal diverticulosis demonstrates a significant association with obstructing or incidental appendiceal neoplasms. It may play an important role in the development of pseudomyxoma peritonei, which is associated with appendiceal mucinous tumors. Therefore, meticulous gross examination and thorough histological examination of the entire appendicectomy specimen are essential. When discovered either by preoperative radiological investigations or during an exploratory operation, prophylactic appendicectomy is advocated to prevent the risk of complications and to rule out the possibility of a coexisting neoplasm.

Gene expression profiling by DNA microarray analysis is a technique with great promise in cancer biology. The multifocality and heterogeneity of many prostate cancers makes the collection of adequate biological samples for such profiling particularly challenging. Current methods, such as laser capture microdissection, are not widely available and can have significant limitations. In this article, a novel method of prostatic sampling, which does not affect the histopathological assessment of the surgical specimen and provides adequate RNA yield for microarray analysis is described. This method is simple, inexpensive, easily reproducible, and has been validated as having >95% sensitivity and 99% specificity for histological prediction of tissue obtained. This method can be adopted by other investigators to perform DNA microarray analysis on prostate tumors.

This study investigated if tumor-associated tissue eosinophilia (TATE) could be associated with the process of tissue invasion in oral squamous cell carcinomas (OSCCs) and its influence on patient's prognosis. Forty-three patients treated for OSCCs with or without lymph nodes involvement, at A. C. Camargo Cancer Hospital, Brazil, were selected for TATE analysis. Two degrees of tissue eosinophilia were established in OSCC: absent/mild and intense. The TATE was evaluated in relation to the clinicopathological features and prognostic value using χ ² test and the Kaplan—Meier method. Most of the patients with OSCC in advanced clinical stage presented muscular infiltration and significantly intense TATE whereas those with tumors in early stage frequently showed absent/mild eosinophilia (P = .009). The TATE showed no prognostic value for 5-year and 10-year survival rates of the OSCC. These findings suggest that intense TATE seems to reflect the stromal invasion of the OSCCs that occur in advanced clinical stage.

This study reports a series of 19 extrapleural solitary fibrous tumors. The patients included 6 men and 13 women with age ranging from 27 to 86 years. Three patients showed local recurrence. In 2 tumors, a diagnosis of malignancy was made. All of the tumors were strongly positive for CD34, and 3 of them expressed high levels of progesterone receptor. Solitary fibrous tumors are fairly rare, occurring in many parts of the body, and their behavior is unpredictable.

This study retrospectively reviewed the clinicopathological features of thymic epithelial tumors in 108 patients, and evaluated World Health Organization (WHO) histologic classification of thymic tumors. Other prognostic factors, including age, gender, clinical stage, and completeness of tumor resection were also analyzed. Seven type A tumors, 19 type AB, 23 type B1, 19 type B2, 27 type B3, and 13 thymic carcinomas were studied. The 5-year and 10-year survival rates were 100% after resection of tumor types A and AB; 93% and 81% for B1; 83% and 70% for B2; and 43% and 33% for B3. The overall 5-year and 10-year survival rates were 72.0% and 63.0%, respectively. Tumor classification was highly significant in predicting survival (P .001) and also reflected the clinical behavior of tumors. The Masaoka stage was the most important independent prognostic index in thymomas. The WHO histologic subtype and completeness of resection were also important prognostic factors.

The Antopol-Goldman lesion is a subepithelial pelvic hematoma simulating a renal neoplasm. We report the clinico-pathological features of a single case and a review of the literature. A 76-year-old man presented with flank pain and hematuria. Computed tomography showed a hypodense lesion of 6 cm at the left kidney with filling defect at pyelogram. The patient underwent nephroureterectomy for suspected neoplasm. Macroscopically, a mass of 6 cm was present impinging on the pelvi-caliceal system. Microscopically, the lesion was composed by hemorragic material with feature of an hematoma. A diffuse eosinophilic amorphous material suspicious for amyloid was observed among intra- and extraparenchymal vessels. The Congo-Red staining verified the presence of amyloid. The diagnosis was subepithelial pelvic hematoma with severe amyloidosis. Antopol-Goldman lesion should be kept in mind as a possible differential diagnosis of upper urinary tract lesion to avoid unnecessary nephrectomies. The anamnestic knowledge of amiloydosis may increase this diagnostic hypothesis.