Shashi Madan

Sarcomatoid mesothelioma and its histological mimics: a comparative immunohistochemical study

Aims:  Differentiating sarcomatoid mesothelioma from other pleural‐based spindle cell tumours by light microscopy can be challenging, especially in a biopsy. The role of immunohistochemistry in this differential diagnosis is not as well defined as it is for distinguishing epithelioid mesothelioma from adenocarcinoma. In this study, we investigate the utility of diagnostic immunohistochemistry for distinguishing sarcomatoid mesothelioma from its histological mimics, high‐grade sarcoma and pulmonary sarcomatoid carcinoma.

Activity of dolastatin 10 against small-cell lung cancer in vitro and in vivo: induction of apoptosis and bcl-2 modification.

Purpose: Dolastatin 10 is a natural cytotoxic peptide which acts through the inhibition of microtubule assembly. Studies have suggested that such agents can induce apoptosis in association with bcl-2 phosphorylation. Since bcl-2 overexpression is common in small-cell lung cancer (SCLC), we evaluated the activity of dolastatin 10 in SCLC cell lines and xenografts. Methods: In vitro growth inhibition was evaluated with a standardized MTT assay and apoptosis with fluorescent microscopy and a TUNEL assay. Immunoblot analysis and phosphatase digestion were used to determine bcl-2 modification. In vivo activity was evaluated in subcutaneous and metastatic SCLC xenograft models in SCID mice. Results: Dolastatin 10 had growth inhibitory activity against four SCLC cell lines (NCI-H69, -H82, -H446, -H510) with IC50 values ranging from 0.032 to 0.184 nM. All four cell lines exhibited evidence of apoptosis after 48 h of exposure to 1.3 nM dolastatin 10. Immunoblot analysis revealed that 1.3 nM dolastatin 10 altered the electrophoretic mobility of bcl-2 in NCI-H69 and -H510 cells within 16 h of treatment. Incubation of protein extract from dolastatin 10-treated NCI-H69 and -H510 cells with calcineurin resulted in the disappearance of the altered mobility species, suggesting dolastatin 10-induced bcl-2 phosphorylation. In in vivo studies, 450 μg/kg of dolastatin 10 IV × 2 given after intravenous injection of NCI-H446 cells completely inhibited tumor formation. In established subcutaneous NCI-H446 xenografts, 450 μg/kg of dolastatin 10 IV induced apoptosis in the majority of tumor cells within 96 h, resulting in a log10 cell kill of 5.2 and an increase in median survival from 42 to 91 days. Conclusions: These findings suggest that dolastatin 10 has potent activity against SCLC and that the modulation of apoptotic pathways deserves further evaluation as an anticancer strategy.

Fine-needle aspiration biopsy of vertebral and intervertebral disc lesions: Specimen adequacy, diagnostic utility, and pitfalls

BACKGROUND AND OBJECTIVES Fine-needle aspiration biopsy (FNAB) is used extensively in the clinical workup of radiologically detected bony lesions. The aims of this study were to evaluate the diagnostic utility of FNAB of such radiologically detected vertebral and intervertebral disc lesions in patients with and without a known primary malignancy, to establish criteria for specimen adequacy, and to evaluate the diagnostic pitfalls. DESIGN The cytologic material obtained by FNAB performed under computed tomographic guidance of 78 cases comprising 66 vertebral and 12 intervertebral disc lesions was reviewed and analyzed. The initial cytologic diagnosis was compared with the diagnosis after review in all 78 cases. RESULTS Thirty-five cases (45%) were positive for malignancy, 1 case (1.3%) was suspicious for malignancy, 9 (11.5%) consisted of normal cellular elements with no evidence of malignancy, 21 (27%) were unsatisfactory/inadequate for diagnosis, and 12 (15.2%) were benign nonneoplastic lesions. Nonneoplastic lesions diagnosed included fracture callus, discitis/osteomyelitis, degenerative disc disease, and Paget disease. In 11 cases, FNAB gave the initial diagnosis of malignancy (8 occult carcinomas and 3 plasmacytomas). In 23 out of 36 cases with a clinical history of a known primary tumor, FNAB established the diagnosis of metastases, and in 1 case, a second primary was detected. CONCLUSIONS Fine-needle aspiration biopsy of radiologically suspected vertebral and intervertebral disc lesions in patients with a history of a known malignancy is useful to confirm the presence of metastases. In cases without any history of malignancy, FNAB can provide additional clues to aid in the subsequent workup and treatment of cases diagnosed with an unsuspected malignancy and other nonneoplastic lesions. Through assessment of the specimen adequacy, correct interpretation of the cytologic material available, and correlating with the clinical and radiologic findings, a definitive diagnosis can be made in most cases.

Ameloblastic carcinoma of the maxilla.

Ameloblastic carcinoma is an unusual tumour. There have been a total of 34 cases of ameloblastic carcinoma in the English literature to date. Of these only 11 cases have occurred in the maxilla. The authors report the 12th such case. The histological classification for odontogenic carcinoma has been debated for many years and recently revised, thus differentiating between malignant ameloblastoma and ameloblastic carcinoma. The authors review the current literature regarding diagnosis and treatment of this unusual lesion, and support the use of the term malignant ameloblastoma for the tumours that metastasize in spite of their benign histological appearance, whereas, the ameloblastic carcinoma is referred to as the primary tumour with malignant transformation, regardless of its metastatic potential.

Sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid: a case report and review of the literature

We present the clinical and histopathologic findings of a 38-year-old woman recently diagnosed with sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid (SMECE). This case is of particular interest because of its extremely aggressive clinical course. After total thyroidectomy, there was extensive bilateral thyroid lobe involvement with extension into perithyroidal soft tissues and the modified radical neck dissection contained 35 of 35 positive lymph nodes. This patient underwent 2 further surgeries; the first was a second right neck and supraclavicular surgery for lymph node metastases in which 8 of 11 were positive, followed a few months later by posterior neck surgery in which multiple lymph nodes were positive. Tumor was also documented by histological review from a right axillary lymph node. Imaging evidence of tumor in the lungs and liver was also present. Establishing the correct diagnosis of SMECE involves an awareness of the cyto- and histomorphologic features of this rare malignancy. As evidence that the biologic behavior of this neoplasm may well be more aggressive than previously considered, we briefly present the clinical and biologic course of this patients neoplasm and a review of the literature.

A universal method for the mutational analysis of K-ras and p53 gene in non-small-cell lung cancer using formalin-fixed paraffin-embedded tissue.

The p53 tumor suppressor gene has been found to be altered in almost all human solid tumors, whereas K-ras gene mutations have been observed in a limited number of human cancers (adenocarcinoma of colon, pancreas, and lung). Studies of mutational inactivation for both genes in the same patients sample on non-small-cell lung cancer have been limited. In an effort to perform such an analysis, we developed and compared methods (for the mutational detection of p53 and K-ras gene) that represent a modified and universal protocol, in terms of DNA extraction, polymerase chain reaction (PCR) amplification, and nonradioisotopic PCR-single-strand conformation polymorphism (PCR-SSCP) analysis, which is readily applicable to either formalin-fixed, paraffin-embedded tissues or frozen tumor specimens. We applied this method to the evaluation of p53 (exons 5–8) and K-ras (codon 12 and 13) gene mutations in 55 cases of non-small-cell lung cancer. The mutational status in the p53 gene was evaluated by radioisotopic PCR-SSCP and compared with PCR-SSCP utilizing our standardized non-radioisotopic detection system using a single 6-μm tissue section. The mutational patterns observed by PCR-SSCP were subsequently confirmed by PCR-DNA sequencing. The mutational status in the K-ras gene was similarly evaluated by PCR-SSCP, and the specific mutation was confirmed by Southern slot-blot hybridization using 32P-labeled sequence-specific oligonucleotide probes for codons 12 and 13. Mutational changes in K-ras (codon 12) were found in 10 of 55 (18%) of non-small-cell lung cancers. Whereas adenocarcinoma showed K-ras mutation in 33% of the cases at codon 12, only one mutation was found at codon 13. As expected, squamous cell carcinoma samples (25 cases) did not show K-ras mutations. Mutations at exons 5–8 of the p53 gene were documented in 19 of 55 (34.5%) cases. Ten of the 19 mutations were single nucleotide point mutations, leading to amino acid substitution. Six showed insertional mutation, and three showed deletion mutations. Only three samples showed mutations of both K-ras and p53 genes. We conclude that although K-ras and p53 gene mutations are frequent in non-small-cell lung cancer, mutations of both genes in the same patients samples are not common. We also conclude that this universal nonradioisotopic method is superior to other similar methods and is readily applicable to the rapid screening of large numbers of formalin-fixed, paraffin-embedded or frozen samples for the mutational analysis of multiple genes.

Dual color multiplex TTF-1 + Napsin A and p63 + CK5 immunostaining for subcategorizing of poorly differentiated pulmonary non-small carcinomas into adenocarcinoma and squamous cell carcinoma in fine needle aspiration specimens

Background: The distinction of lung adenocarcinoma (ADC) from squamous cell carcinoma (SCC) has important therapeutic implications. Napsin A is a recently developed marker, which has shown high specificity for lung tissue in the surgical pathology specimens. In this study, we have evaluated whether the use of a panel of novel multiplex cocktails of TTF-1 + Napsin A and p63 + CK5 for dual color immunostaining will improve the diagnostic accuracy of lung adenocarcinoma and squamous cell carcinoma in fine needle aspiration (FNA) specimens, usually with relatively scant microfragments of diagnostic material. Materials and Methods: Formalin-fixed, paraffin-embedded, adequately cellular FNA cell blocks with a confirmed diagnosis of either ADC (n = 22), SCC (n = 20) or poorly differentiated carcinoma (PDC; n = 7), from a total of 49 consecutive cases, were studied. All these cases had subsequently confirmed diagnosis in biopsies or resection specimens. The sections were immunostained with two color methods of TTF-1 + Napsin A and p63 + CK5 multiplex cocktails. The presence of one or more unequivocal individual tumor cells with convincing brown nuclear TTF-1 and red cytoplasmic Napsin A staining, and cells with brown nuclear p63 and membranous / cytoplasmic CK5 staining were interpreted as ‘positive’. Results: All 20 FNA cell blocks from SCC cases were positive for dual stain p63 + CK5 and negative for dual stain TTF-1 + Napsin A. The sensitivity and specificity of the dual immunoexpressions of p63 + CK5 for SCC of lung FNAs were both 100%. All 22 ADC cases were positive with dual stain of TTF-1 + Napsin A and negative for dual stain of p63 + CK5. On follow-up of the surgical pathology specimens, 22 cases were confirmed as ADC. The sensitivity of the dual immunoexpression of TTF-1 + Napsin A for ADC of lung FNAs was 100% and the specificity was also 100%. Of the seven PDC cases, five cases that were positive for dual stain p63 + CK5 and negative for dual stain TTF-1 + Napsin A could be categorized as SCC. Two of the seven (2 / 7) PDC cases were positive for dual stain TTF-1 + Napsin A and negative for dual stain p63 + CK5, consistent with ADC. Conclusions: Simultaneous coordinate or individual immunostaining for Napsin A / TTF-1 in ADC and p63 / CK5 in SCC demonstrated high sensitivity and specificity. The panel with multiplex Napsin A / TTF-1 and p63 / CK5 dual color immunostains could specifically subcategorize PDC into ADC and SCC in lung FNA specimens. Multiplex dual color Napsin A / TTF-1 and p63 / CK5 immunostaining is especially recommended for evaluation of FNA specimens with relatively scant cellularity.

Metastatic colorectal adenocarcinoma in cervicovaginal cytology specimens confirmed by immunocytochemical stains on liquid base specimens: Two study cases with review of the literature

Only a few cases of adenocarcinoma (ACA) metastatic to the female lower genital tract diagnosed on cervicovaginal Pap smear have been reported during the past several decades. Both conventional and liquid based cytology (LBC) have limited sensitivity and specificity in diagnosing metastatic disease and immunocytochemical (ICC) staining may be needed for confirming the diagnosis. We present two cases of metastatic colorectal ACA diagnosed on cervicovaginal ThinPrep (TP) Pap smears, with one confirmed by ICC staining method. Recognition of extra-uterine malignancy in the cervicovaginal cytology specimen is critical for the disease diagnosis, prognosis, and the treatment. ICC staining performed on the residual LBC specimen is an important methodology to confirm the diagnosis.

Etiologic factors related to unsatisfactory ThinPrep® cervical cytology: Evaluation and potential solutions to improve

Background: In cervical cytology, the unsatisfactory rates for ThinPrep (TP) are slightly higher compared to SurePath. We examined various causes and explored potential for resolution of this discrepancy. Materials and Methods: Totally, 19,422 cases were reviewed and 1000 unsatisfactory specimens were selected and analyzed. 531 specimens were available for wash protocol. Out of 114 unsatisfactory specimens associated with atrophic cellular changes (ACC), 48 were resubmitted by provider and reevaluated. Results: Lubricant and lubricant-like debris/contamination (LUBE) was the most common cause of unsatisfactory specimens (68%; 681/1000) followed by blood (7.5%); ACC only (without other interfering factors) (2.4%); inflammation (3.0%); and combinations thereof (1.9%). 11.5% showed scant cellularity without an identifiable cause. 3.3% were virtually acellular. Wash protocol improved cellularity in 48% (256/531) of cases. However, only 29% (73/256) of those were satisfactory (with more than 5000 cells). Quantitative reduction in LUBE after wash protocol varied with different morphological subtypes. Interpretation patterns on satisfactory specimens after wash protocol were comparable to the results on selected cohort of specimens during the same study period. Out of 114 ACC, wash protocol was performed on 68 ACC specimens leading to satisfactory TP in 24% (16/68). Totally, 48 cases reported as unsatisfactory with ACC, were resubmitted by the providers between 2 weeks and 2 years. 44 (92%) showed increased cellularity, out of which 52% (23/44) did not show ACC. Conclusion: LUBE was the most common cause of unsatisfactory TP in addition to interference by blood and association with atrophic changes. Knowing the morphological spectrum of LUBE would help to identify it as the cause of unsatisfactory TP. Communicating the cause of unsatisfactory TP such as LUBE, ACC, and blood would hint the provider to take appropriate precaution during submission of the repeat specimen, leading to improved patient care.

Nephrectomy in the Management of Metastatic Osteosarcoma

This report discusses a rare case of nephrectomy for metastatic osteosarcoma, the first performed laparoscopically, and proposes such management as a standard of care. A 21-year-old woman with a history of metastatic osteosarcoma involving her right kidney was referred to our institution for evaluation. She was managed with a hand-assisted laparoscopic nephrectomy. An exhaustive review of the English literature pertaining to this disease was performed. To our knowledge, this case represents only the sixth nephrectomy ever reported for metastatic osteosarcoma and the first performed by a laparoscopic approach. In addition, this is the first reported case of this disease invading the renal vein. The literature suggests that the incidence of renal involvement in osteosarcoma is significant and that renal imaging should be mandatory in such patients. When renal metastases are diagnosed, prompt nephrectomy is warranted. A minimally invasive approach in these patients should be considered.