Progression of gingival squamous cell carcinoma from early to late stage after invasive dental procedure.

Early presentation of gingival squamous cell carcinoma (GSCC) is at times misdiagnosed as a benign inflammatory or reactive oral condition. Some misdiagnosed patients undergo unnecessary, invasive dental procedures, resulting in delayed cancer diagnosis and an increased risk of accelerated disease progression due to disruption of the periosteum and cortical bone. The records of 58 patients with biopsy-proven GSCC were retrospectively reviewed. The sample included 32 patients who underwent an invasive dental procedure (IDP) prior to cancer diagnosis and 26 patients who did not undergo an IDP (non-case group). Patients from both groups initially presented with similar symptoms. The median duration of symptoms at initial clinical presentation was 6 months for the IDP group and 2 months for the non-case group. In IDP patients, symptoms worsened after the IDP was rendered, with 37.5% presenting with a severe-grade symptom. In both groups, the majority of lesions were found on the posterior mandible and had a histologic grading of moderately differentiated GSCC. The odds of the IDP group having late-stage disease were 2.94 times greater than the odds for the control group. Stage T3/T4 malignancy was diagnosed in 77.4% of the IDP patients versus 53.8% of non-case patients. Disease-specific mortality was comparable; however, surgical treatment was significantly more extensive in the IDP group than in the non-case group. The disruption of alveolar periosteum in undiagnosed oral cancer patients results in significant delay in diagnosis, necessitating more complicated treatment regimens because of local tumor progression.

Pretreatment weight status and weight loss among head and neck cancer patients receiving definitive concurrent chemoradiation therapy: implications for nutrition integrated treatment pathways.

PURPOSE: The purpose was to examine the effect of pretreatment weight status on loco-regional progression for patients with squamous cell carcinoma of the head and neck (SCCHN) after receiving definitive concurrent chemoradiation therapy (CCRT). METHODS: In an expanded cohort of 140 patients, we retrospectively reviewed weight status and loco-regional progression of SCCHN patients treated with CCRT between 2004 and 2010. RESULTS: Pretreatment ideal body weight percentage (IBW%) was statistically significantly different for patients with disease progression than for those without progression (p = 0.02) but was not an independent predictor of progression. Median pretreatment IBW% was 118 (72-193) for the progression-free group and was 101.5 (73-163) for the group with progression. Both groups suffered clinically severe weight loss of approximately 9 % from baseline to end treatment. CONCLUSIONS: Pretreatment weight status, a very crude indicator of nutrition status, may have prognostic value in patients with SCCHN undergoing definitive CCRT. Inadequate nutritional status in these patients has been associated with poor clinical outcomes and decreased quality of life. Based on this report and others, the best next steps include routine validated malnutrition screening and the testing of evidence-based nutrition care protocols with the goals of minimizing weight loss and improvement of quality of life.

Pectoralis major myocutaneous flap for reconstruction of circumferential pharyngeal defects.

BACKGROUND: A 270-degree partially tubed pectoralis major myocutaneous flap (PMMF) is an excellent option for total circumferential pharyngoesophageal defects in patients who are not candidates for more complex reconstructions. METHODS: Patients undergoing circumferential pharyngoesophageal reconstruction with partially tubed PMMF were reviewed. End points were stricture, fistula, resumption of oral intake, perioperative death, and recurrence. RESULTS: Eleven patients underwent 270-degree PMMF for reconstruction: 6 (55%) were men and 5 (45%) were women (mean, 62 years; range, 42-78 years). Three patients (27%) developed fistulas and 2 (18%) developed stenosis. Ten patients (91%) were able to resume adequate nutrition via oral intake. There were no perioperative deaths. CONCLUSIONS: Patients with severe comorbidities, metastatic disease, a lack of donor vessels, or a potentially hostile abdomen may not be ideal candidates for free tissue transfer. For these patients, partially tubed PMMF using the prevertebral fascia provides a reliable alternative for reconstruction with excellent functional results.

Monitoring photobleaching and hemodynamic responses to HPPH-mediated photodynamic therapy of head and neck cancer: a case report.

We present initial results obtained during the course of a Phase I clinical trial of 2-1[hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH)-mediated photo-dynamic therapy (PDT) in a head and neck cancer patient. We quantified blood flow, oxygenation and HPPH drug photobleaching before and after therapeutic light treatment by utilizing fast, non-invasive diffuse optical methods. Our results showed that HPPH-PDT induced significant drug photobleaching, and reduction in blood flow and oxygenation suggesting significant vascular and cellular reaction. These changes were accompanied by cross-linking of the signal transducer and activator of transcription 3 (STAT3), a molecular measure for the oxidative photoreaction. These preliminary results suggest diffuse optical spectroscopies permit non-invasive monitoring of PDT in clinical settings of head and neck cancer patients.

Challenges in array comparative genomic hybridization for the analysis of cancer samples.

PURPOSE: To address some of the challenges facing the incorporation of array comparative genomic hybridization technology as a clinical tool, including archived tumor tissue, tumor heterogeneity, DNA quality and quantity, and array comparative genomic hybridization platform selection and performance. METHODS: Experiments were designed to assess the impact of DNA source (e.g., archival material), quantity, and amplification on array comparative genomic hybridization results. Two microdissection methods were used to isolate tumor cells to minimize heterogeneity. These data and other data sets were used in a further performance comparison of two commonly used array comparative genomic hybridization platforms: bacterial artificial chromosome (Roswell Park Cancer Institute) and oligonucleotide (Agilent Technologies, Santa Clara, CA). RESULTS: Array comparative genomic hybridization data from as few as 100 formalin-fixed, paraffin-embedded cells isolated by laser capture microdissection and amplified were remarkably similar to array comparative genomic hybridization copy number alterations detected in the bulk (unamplified) population. Manual microdissection from frozen sections provided a rapid and inexpensive means to isolate tumor from adjacent DNA for amplification and array comparative genomic hybridization. Whole genome amplification introduced no appreciable allele bias on array comparative genomic hybridization. The array comparative genomic hybridization results provided by the bacterial artificial chromosome and Agilent platforms were concordant in general, but bacterial artificial chromosome array comparative genomic hybridization showed far fewer outliers and overall less technical noise, which could adversely affect the statistical interpretation of the data. CONCLUSIONS: This study demonstrates that copy number alterations can be robustly and reproducibly detected by array comparative genomic hybridization in DNA isolated from challenging tumor types and sources, including archival materials, low DNA yield, and heterogeneous tissues. Furthermore, bacterial artificial chromosome array comparative genomic hybridization offers the advantage over the Agilent oligonucleotide platform of presenting fewer outliers, which could affect data interpretation.

Idiosyncrasies of scalp melanoma.

OBJECTIVES/HYPOTHESIS: Examine the accuracy of sentinel lymph node biopsy (SNB) in scalp melanoma (SM), patterns of nodal metastases, patient outcomes, and the utility of immunohistochemistry (IHC) in SNB evaluation. STUDY DESIGN: Retrospective. METHODS: There were 22 patients, 4 females and 18 males. Sentinel lymph nodes (SLN) were localized via preoperative lymphoscintigraphy, intraoperative gamma probe, and Lymphazurin injection. SLNs were stained with hematoxylin-eosin, S-100, HMB-45, Melan-A, micropthalmia transcription factor, and tyrosinase. SLNs were grouped into cervical (levels 1-5) and extracervical (parotid, suboccipital, retroauricular) regions. RESULTS: There were 13 posterior and 9 anterior SMs. The first SNB were mapped to the extracervical regions in 77% of posterior and 78% of anterior lesions. SLN number ranged from 1 to 5. Ten patients had positive SLNs (PSLN). Forty percent of the PSLN group had SLNs mapped in both cervical and extracervical sites. Six underwent completion lymphadenectomy, with no additional positive nodes identified. No significant difference between PSLN and negative sentinel node (NSLN) patients was seen when compared by SLN number, Breslow's thickness, tumor ulceration, and clinical outcomes. Mean follow-up was 35 months. One patient died of disease. One isolated regional recurrence occurred. Sixty percent of PSLN and 92% of NSLN patients were recurrence free at last follow-up. One distant metastasis occurred in the NSLN group, and one local, one regional, and two patients with distant metastases were in the PSLN group at the time of last follow-up. Additional IHC did not detect other metastases in the NSLN group. CONCLUSIONS: SM is aggressive, as demonstrated by the high rate of SLN metastases, and there were no significant histopathologic factors in the primary tumor that predicted the presence of SLN metastases. SNB was accurate. The majority of first SLNs were localized in extracervical basins.

Comparative genomic instabilities of thyroid and colon cancers.

OBJECTIVES: To assess the forms and extent of genomic instability in thyroid cancers and colorectal neoplasms and to determine if such measurements could explain the generally excellent prognosis of thyroid malignant neoplasms compared with colon carcinoma. DESIGN: Tumor genome analyses. Genomic instability was measured by the following 4 methods, listed in ascending order based on the size of events detected: inter-simple sequence repeat polymerase chain reaction (ISSR-PCR), fractional allelic loss (FAL) analysis, array-based comparative genomic hybridization (aCGH), and spectral karyotyping (SKY). RESULTS: The genomic instability index of 32 thyroid carcinomas, 59 colon carcinomas, and 11 colon polyps was determined by ISSR-PCR; no difference was seen among the 3 groups by this method. Fractional allelic loss rates were comparable in thyroid cancers and colon polyps and lower than FAL rates in colorectal cancers. Indolent papillary thyroid carcinomas were essentially diploid with no large-scale alterations in chromosome number or structure when evaluated by aCGH or SKY. In anaplastic thyroid cancers, aCGH revealed abundant chromosome alterations. Colorectal carcinomas showed extensive copy number changes and chromosomal rearrangements when analyzed by aCGH and SKY. CONCLUSIONS: Genomic alterations in papillary thyroid carcinoma, such as in benign colon polyps, are principally smaller events detected by ISSR-PCR. With the more aggressive tumor types (ie, anaplastic thyroid and colorectal carcinomas), larger events detected by FAL analysis, aCGH, and SKY were revealed. We hypothesize that mutations caused by smaller genomic alterations enable thyroid cells to achieve a minimal malignant phenotype. Mutations for aggressive biological behavior appear with larger genomic events.

The introducer technique is the optimal method for placing percutaneous endoscopic gastrostomy tubes in head and neck cancer patients.

BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) tubes are often placed in head and neck cancer patients to provide nutritional support, but studies have found the complication rates to be higher than other subsets of patients who undergo PEG placement. Complication rates as high as 50% have been reported, with the bulk of these complications being PEG site issues (i.e., cellulitis, abscess, fascitis, and tumor implantation). Because the pull technique has been the primary technique used, the theory is that the transoral tube passage is the source of the complications in these patients. Alternatively, the introducer technique uses a transabdominal approach to place the device, avoiding any tube contamination by upper aerodigestive organisms or tumor cells. At our institution, this technique has been used exclusively for head and neck cancer patients and this article reports our experience. METHODS: One hundred forty-nine head and neck cancer patients who had a prophylactic PEG tube placed were reviewed from January 1, 1999 to December 31, 2003. The rates of placement success, morbidity, and complications were determined. RESULTS: Successful placement was achieved in 148 (99%) patients without any PEG-related deaths. Overall, 17 complications (11%) occurred, with only one major complication (0.7%) identified. PEG site infections were uncommon with only five cases (3.4%) and all were mild cellulitis. CONCLUSIONS: The introducer technique is the safest method for PEG tube placement in head and neck cancer patients. The overall rate of complications is low and PEG site infectious complications are rare. The introducer technique should be the method of choice for PEG tubes in head and neck cancer patients.

Intraparotid sentinel lymph node biopsy for head and neck melanoma.

OBJECTIVE: The objective of this retrospective clinical review was to assess the safety and accuracy of intraparotid sentinel node biopsy in patients with melanoma. SETTING: This study was conducted at a tertiary referral center. PATIENTS: Twenty-eight patients with cutaneous melanoma of the head and neck undergoing sentinel lymph node (SLN) biopsy in which the radionuclide localized to the parotid gland on preoperative lymphoscintigraphy were studied. METHODS: All patients underwent wide local excision of the tumor and intraparotid sentinel node biopsy using intraoperative gamma probe localization. RESULTS: There were 25 men and 3 women ranging in age from 34 to 81 years. The primary site was on the auricle in 14 patients: temple, 4; forehead, 5; cheek, 3; and on the neck in 2 patients, respectively. The mean Breslow thickness was 2.3 mm (range, 0.9-7.0 mm). In 27 of 28 patients, an intraparotid SLN was identified. In one patient, final pathology did not reveal lymphoid tissue despite a high count in the parotid tissue excised. Median number of SLN per patient was two. Six patients had microscopic metastases in the SLN. In two of these patients, additional microscopic lymph node metastases were found in the neck after subsequent formal lymphadenectomy. The pathologic staging for the group (n = 14) was: stage 1B, 4; 2A, 4; stage 2B, 3; and stage 3B, 3 patients, respectively. All patients are alive and without evidence of disease (mean follow up, 31 months). There were no surgical complications, specifically no patient experienced temporary or permanent facial paralysis. CONCLUSION: Intraparotid SLN biopsy for staging cutaneous head and neck melanoma is a reliable, accurate, and safe procedure.

Chemoprevention of head and neck cancer with aspirin: a case-control study.

OBJECTIVE: To evaluate the chemopreventive potential of aspirin against head and neck cancer. DESIGN: Hospital-based case-control study. SETTING: National Cancer Institute-designated comprehensive cancer center. Patients Individuals who received medical services at the Roswell Park Cancer Institute, Buffalo, NY, between 1982 and 1998 and who completed a comprehensive epidemiologic questionnaire. MAIN OUTCOME MEASURE: Aspirin use among 529 patients with head and neck cancer and 529 hospital-based control subjects matched by age, sex, and smoking status. RESULTS: Aspirin use was associated with a 25% reduction in the risk of head and neck cancer (adjusted odds ratio, 0.75; 95% confidence interval, 0.58-0.96). Consistent risk reductions were also noted in association with frequent and prolonged aspirin use. Further, a consistently decreasing trend in risk was noted with increasing duration of aspirin use (P(trend) = .005). Risk reduction was observed across all 5 primary tumor sites, with cancers of the oral cavity and oropharynx exhibiting greater risk reduction. When analyzed by smoking and alcohol exposure levels, participants moderately exposed to either showed a statistically significant 33% risk reduction (adjusted odds ratio, 0.67; 95% confidence interval, 0.50-0.91), whereas participants exposed to both heavy smoking and alcohol use did not benefit from the protective effect of aspirin. The reduction in risk was relatively more significant in women. CONCLUSIONS: Aspirin use is associated with reduced risk of head and neck cancer. This effect is more pronounced in individuals with low to moderate exposure to cigarette smoke or alcohol consumption.

Photodynamic therapy with 3-(1'-hexyloxyethyl) pyropheophorbide-a for early-stage cancer of the larynx: Phase Ib study.

BACKGROUND: The purpose of this study was for us to report results regarding the safety of 3-(1'-hexyloxyethyl) pyropheophorbide-a (HPPH) mediated photodynamic therapy (PDT) in early laryngeal disease, and offer preliminary information on treatment responses. METHODS: A single-institution, phase Ib, open label, noncomparative study of HPPH-PDT in patients with high-risk dysplasia, carcinoma in situ, and T1 squamous cell carcinoma (SCC) of the larynx. The primary outcomes were safety and maximum tolerated dose (MTD), and the secondary outcome was response. RESULTS: Twenty-nine patients and 30 lesions were treated. The most common adverse event (AE) was transient hoarseness of voice. Severe edema, requiring tracheostomy, was the most serious AE, which occurred in 2 patients within several hours of therapy. The MTD was 100 J/cm(2) . Patients with T1 SCC seemed to have good complete response rate (82%) to HPPH-PDT at MTD. CONCLUSION: HPPH-PDT can be safely used to treat early-stage laryngeal cancer, with potential efficacy. © 2015 The Authors Head & Neck Published by Wiley Periodicals, Inc. Head Neck 38: E377-E383, 2016.

Development of head and neck squamous cell carcinoma is associated with altered cytokine responsiveness.

Growth of head and neck squamous cell carcinoma (HNSCC) is generally associated with an inflammatory component. It is hypothesized that these tumor cells develop mechanisms to evade the growth inhibitory effects of cytokines that are present in the tumor microenvironment. This study determined the changes in responsiveness to inflammatory cytokines that accompany the transition of normal to transformed epithelial cells. Paired primary cultures of normal epithelial cells (NEC) and SCC cells were established from 16 patients. Receptor-mediated activation of signal transducer and activator of transcription and extracellular signal-regulated kinase pathways in response to cytokine treatments was identified by immunoblot analysis. Thymidine incorporation determined the impact of the cytokines on DNA synthesis. HNNEC and HNSCC displayed a prominent signaling in response to oncostatin M, interleukin-6, IFN-gamma, and epidermal growth factor. Untreated HNSCC showed an elevated level of phosphorylated signal transducer and activator of transcription 3 and extracellular signal-regulated kinase (P < 0.001) compared with HNNEC, suggesting constitutively activated pathways. Moreover, HNSCC cells phosphorylated significantly more signal transducer and activator of transcription 1 in response to oncostatin M (P = 0.002) and IFN-gamma (P = 0.018) treatments. DNA synthesis of SCC cells was less inhibited by cytokines produced by endotoxin-stimulated macrophages (P = 0.016) than that of NEC. Low-dose oncostatin M slightly enhanced proliferation of SCC, whereas that of NEC was suppressed (P = 0.016). This study identified significant alterations in signal transduction pathways engaged by cytokines and which are associated with loss of growth inhibition of HNSCC. Increased signal transducer and activator of transcription phosphorylation, along with constitutively phosphorylated extracellular signal-regulated kinase in HNSCC, suggest that these pathways as molecular markers are important in the malignant transformation process and are potential targets for treatment.

Is there disparity in the care of minority patients with upper aerodigestive tract malignancy?

The data presently available indicate that there is unequal (disparate) care in patients with head and neck cancer. The reasons for this are likely multifactorial and require further study. Complicating such work is the need for subgroup analysis. For example, Hispanics are not a homogeneous ethnic group; hence, differences in social perception, cultural mores, and available medical resources can be demonstrated that can directly impact care and outcome. Appropriate epidemiologic studies are needed with more underserved minority patients to analyze these differences further and to address such differences.

Sentinel lymph node biopsy: a rational approach for staging T2N0 oral cancer.

OBJECTIVES/HYPOTHESIS: For oral cancer patients, the presence of neck nodal metastases is the most important disease prognosticator. However, a significant proportion of clinically N0 patients harbor occult microscopic nodal metastasis. Our objective was to determine the feasibility and accuracy of sentinel node biopsy (SNB) in the staging of T2N0 oral carcinoma patients. STUDY DESIGN: Prospective analysis. METHODS: Twenty patients with previously untreated N0 oral cavity squamous cell carcinoma were studied. Each patient had an SNB performed using preoperative technetium sulfur colloid lymphoscintigraphy, intraoperative gamma probe guidance, and intraoperative peritumoral injection of 1% isosulfan blue. All patients underwent neck dissection. The sentinel lymph nodes (SLNs) were sectioned in 2- to 3-mm intervals, formalin fixed, and sectioned at three levels. The non-SLNs were sectioned in a routine manner for histologic examination. RESULTS: SLNs were identified in all patients (100%) and accurately predicted the pathologic nodal status in 18 of 20 patients (90%). Tumor was found exclusively in the SLNs in six patients (30%). Two patients had positive SLNs at multiple neck levels. Two patients had a negative SLN and a positive non-SLN (false-negative findings). Occult nodal metastases were present in 60% of the cohort. CONCLUSIONS: SNB is a technically feasible and accurate procedure for staging the neck in oral carcinoma patients. However, SNB accuracy is lower for floor of the mouth lesions. The rate of occult nodal metastases identified in this cohort is higher than previously reported in the literature. These results suggest that SNB warrants further multi-institutional studies.

Molecular prognosticators and genomic instability in papillary thyroid cancer.

OBJECTIVES/HYPOTHESIS: Tumor progression has been attributed to the accumulation of DNA damage concurrent with selection of advantageous mutations; this DNA damage may result from failure to maintain genomic integrity or from susceptibility to carcinogens. Glutathione S-transferases (GSTs), enzymes that metabolize many carcinogens, may play a role in preserving genome integrity. The objectives of this study are to assess the relationship of GST genotypes with prognosis, clinicopathologic parameters, and genomic instability in papillary thyroid cancer. STUDY DESIGN: Prospective analysis. METHODS: GSTM1 and GSTT1 genotypes of 35 matched normal and papillary thyroid cancer specimens were determined by polymerase chain reaction (PCR) using primers specific for the coding sequences of each gene. Genomic instability was measured by intersimple sequence repeat PCR for each tumor/normal pair and compared with the GAMES prognostic scoring system and clinicopathologic parameters including age, extrathyroidal extension, tumor grade, size, stage metastasis, sex, and smoking history. RESULTS: GSTM1 and GSTT1 null genotypes were found in the normal tissues of 46% and 45%, respectively. No gene losses were detected in the tumor specimens. A significant association between the GSTM1 null genotype and increased risk of recurrence and death was observed. Elevated GII correlated with smoking and tumor stage but not with GST genotype. CONCLUSION: The association of GSTM1 null genotype with intermediate and high risk GAMES categories suggests that GSTM1 provides some protection against disease progression. However, this protection does not confer resistance to disease onset. GST genotyping may be a useful adjunct prognosticator with GAMES.

Tissue eosinophilia: a morphologic marker for assessing stromal invasion in laryngeal squamous neoplasms.

BACKGROUND: The assessment of tumor invasion of underlying benign stroma in neoplastic squamous proliferation of the larynx may pose a diagnostic challenge, particularly in small biopsy specimens that are frequently tangentially sectioned. We studied whether thresholds of an eosinophilic response to laryngeal squamous neoplasms provides an adjunctive histologic criterion for determining the presence of invasion. METHODS: Eighty-seven(n = 87) cases of invasive squamous cell carcinoma and preinvasive squamous neoplasia were evaluated. In each case, the number of eosinophils per high power field(eosinophils/hpf), and per 10 hpf in the tissue adjacent to the neoplastic epithelium, were counted and tabulated. For statistical purposes, the elevated eosinophils were defined and categorized as: focally and moderately elevated (5-9 eos/hpf), focally and markedly increased(>10/hpf), diffusely and moderately elevated(5-19 eos/10hpf), and diffusely and markedly increased (>20/10hpf). RESULTS: In the invasive carcinoma, eosinophil counts were elevated focally and /or diffusely, more frequently seen than in non-invasive neoplastic lesions. The increased eosinophil counts, specifically >10hpf, and >20/10hpf, were all statistically significantly associated with stromal invasion. Greater than 10 eosinophils/hpf and/or >20 eosinophils/10hpf had highest predictive power, with a sensitivity, specificity and positive predictive value of 82%, 93%, 96% and 80%, 100% and 100%, respectively. Virtually, greater than 20 eosinophils/10 hpf was diagnostic for tumor invasion in our series. CONCLUSION: Our study suggests for the first time that the elevated eosinophil count in squamous neoplasia of the larynx is a morphologic feature associated with tumor invasion. When the number of infiltrating eosinophils exceeds 10/hpf and or >20/10 hpf in a laryngeal biopsy with squamous neoplasia, it represents an indicator for the possibility of tumor invasion. Similarly, the presence of eosinophils meeting these thresholds in an excisional specimen should prompt a thorough evaluation for invasiveness, when evidence of invasion is absent, or when invasion is suspected by conventional criteria in the initial sections.

Advanced soft palate cancer: the clinical importance of the parapharyngeal space.

OBJECTIVE: To identify the incidence of parapharyngeal space (PPS) recurrences and how they impact survival in advanced-stage soft-palate carcinoma patients. STUDY DESIGN AND SETTING: One hundred thirty-seven patients' charts were reviewed from 1971 to 1996. Inclusion criteria were patients who received a per-oral resection, discontinuous neck dissection, and postoperative adjuvant radiation therapy; 15 patients met criteria for inclusion. The incidence of PPS recurrences, regional failure, and survival were endpoints that were analyzed. RESULTS: There were no local failures in our study. Regional failures excluding the PPS (levels I-V) were 27%, and 40% occurred within the PPS. Cervical adenopathy was associated with 83% of the PPS recurrences. Median survival for PPS recurrences was 26 months, compared with 67 months for levels I-V recurrences (n = ns). CONCLUSIONS: The incidence of PPS recurrences is substantial in advanced-stage soft-palate cancer. PPS recurrences negatively impact survival; without effective salvage techniques for these recurrences or effective adjuvant therapy, poor patient outcomes can be expected.

Image-guided Interstitial Photodynamic Therapy for Squamous Cell Carcinomas: Preclinical investigation.

OBJECTIVE: Photodynamic therapy (PDT) is a clinically approved minimally invasive treatment for cancer. In this preclinical study, using an imaging-guided approach, we examined the potential utility of PDT in the management of bulky squamous cell carcinomas (SCCs). METHODS: To mimic bulky oropharyngeal cancers seen in the clinical setting, intramuscular SCCs were established in six-to-eight week old female C3H mice. Animals were injected with the photosensitizer, 2-[hexyloxyethyl]-2-devinyl pyropheophorbide-a (HPPH; 0.4 µmol/kg, i.v.) and tumors were illuminated 24 hours post injection with 665 nm light. PDT as a single treatment modality was administered by surface illumination or by interstitial placement of fibers (iPDT). Magnetic resonance imaging was used to guide treatment and assess tumor response to PDT along with correlative histopathologic assessment. RESULTS: Interstitial HPPH-PDT resulted in a marked change on T2 maps 24 hours post treatment compared to untreated controls or transcutaneous illumination. Corresponding apparent diffusion coefficient maps also showed hyperintense areas in tumors following iPDT suggestive of effective photodynamic cell kill. Histologic sections (H&E) confirmed presence of extensive tumor necrosis following iPDT. CONCLUSIONS: These results highlight the potential utility of PDT in the treatment of bulky oropharyngeal cancers. The findings of our study also demonstrate the utility of MRI as a non-invasive tool for mapping of early tissue response to PDT.

Definition of a region of loss of heterozygosity at chromosome 11q23.3-25 in head and neck squamous cell carcinoma using laser capture microdissection technique.

To date, loss of heterozygosity (LOH) studies on HNSCC have had limited success in identifying a confined region of loss on chromosome 11q partially due to the heterogeneous nature of tumor tissue examined. Additionally, little is known about the role of the 11q allelic deletion in HNSCC tumorigenesis and current reports are conflicting. The aim of this study was to better define LOH at distal 11q by using combination of a pure cell population procured by laser capture microdissection (LCM) and subsequent sensitive PCR amplification of polymorphic microsatellites. This study analyzed HNSCC for LOH using a panel of 5 microsatellite markers spanning 11q23-25. Thirty-four paired DNA samples from tumor and autologous normal tissue were harvested by LCM technique to ensure a pure cell population for PCR amplification. Approximately 2000 to 3000 cells were procured from each sample. Twenty-one of 34 cases (62%, P < 0.001) showed LOH on at least one of the loci examined. The highest frequency of LOH was found at the 11q23.3-25 segment, with 44% at marker D11S968 and 35% at marker D11S1316. A distinct novel region of frequent LOH at 11q23.3-25, defined by D11S1316 and D11S968, was identified. No allelic loss was found in any normal squamous tissue samples. To study LOH in HNSCC, combination of pure cell population procurement by LCM and sensitive PCR provides a more accurate approach than the conventional method using a bulk of heterogeneous tissue. A novel region of LOH at 11q23.3-25 was defined. LOH in this region may harbor putative tumor suppressor gene(s) critical for HNSCC. Furthermore, these allelic losses were not found in any non-neoplastic squamous tissue samples, clarifying prior discrepant data.

Sentinel lymph node biopsy in staging of differentiated thyroid cancer: a critical review.

Sentinel lymph node biopsy has recently been utilized to map tumor lymphatics in patients with differentiated thyroid carcinoma. Currently, controversy centers around the feasibility and future role of this technique in the management of differentiated thyroid cancer patients. A review of the current literature in which sentinel lymph node biopsy was performed on patients with a diagnosis of differentiated thyroid cancer was undertaken. Sentinel lymph node biopsy has been carried out on thyroid cancer patients utilizing a vital dye technique, a radiotracer technique, and a combination of both techniques. In the current literature the average rate of sentinel node identification is 91% (range 66-100%) and when identified, the sentinel node accurately predicts the disease status of the neck in most patients (range 80-100%). Limitations to carrying out the sentinel node biopsy on thyroid cancer patients include staining of parathyroid glands, identification of lymph nodes draining into the mediastinum, and the 'shine through' effect. Sentinel lymph node biopsy is technically feasible, but for a disease in which nodal metastases are of debatable prognostic value, the clinical utility of sentinel lymph node biopsy in the management of patients with differentiated thyroid cancer appears less than promising.