Hanna Dahlstrand

Incidence of human papillomavirus (HPV) positive tonsillar carcinoma in Stockholm, Sweden: An epidemic of viral-induced carcinoma?

In the county of Stockholm, between 1970 and 2002, we have previously reported a 3‐fold parallel increase in the incidence of tonsillar squamous cell carcinoma (SCC) and the proportion of human papillomavirus (HPV) positive tonsillar SCC. Here, we have followed the above parameters in all patients (n = 120) diagnosed with tonsillar SCC during 2003–2007 in the same area, and also in correlation to our previous data. Ninety‐eight pretreatment biopsies were available and presence of HPV DNA and HPV‐16 E6 and E7 RNA were tested by polymerase chain reaction (PCR) and RT‐PCR. Incidence data were obtained from the Swedish Cancer Registry. Data reported from 1970 to 2002 were also obtained for comparison. HPV DNA was present in 83 of 98 (85%) of the tonsillar SCC biopsies from 2003 to 2007 and 77 of these were HPV‐16 positive. HPV‐16 E6 and E7 RNA were found in 98% of 52 analyzed HPV‐16 positive cases. The proportion of HPV‐positive cancers had significantly increased both from 1970 to 2007 (p < 0.0001) as well from 2000 to 2007 (p < 0.01), with 68% (95% confidence interval (CI), 53–81) 2000–2002; 77% (95% CI, 63–87) 2003–2005; and 93% (95% CI, 82–99) 2006–2007. The incidence rate of HPV‐positive tumors almost doubled each decade between 1970 and 2007, in parallel with a decline of HPV‐negative tumors. In conclusion, the incidence of HPV‐positive cancers is still increasing in the County of Stockholm, suggesting an epidemic of a virus‐induced carcinoma, with soon practically all tonsillar SCC being HPV positive, as in cervical cancer.

Human papillomavirus as a risk factor for the increase in incidence of tonsillar cancer.

Smoking and alcohol are well‐known etiological factors in tonsillar cancer. However, as in cervical cancer, human papillomavirus (HPV) is currently found in a sizable proportion of tonsillar cancer. Recent reports from the U.S. and Finland show an increase in the incidence of tonsillar cancer, without a parallel rise in smoking and alcohol consumption. This study investigates whether the incidence of tonsillar cancer has also changed in Sweden and whether a possible explanation of the increase is a higher proportion of HPV‐positive tonsillar cancer. The incidence of tonsillar cancer between 1970 and 2002 in the Stockholm area was obtained from the Swedish Cancer Registry. In parallel, 203 pretreatment paraffin‐embedded tonsillar cancer biopsies taken during 1970–2002 from patients in the Stockholm area were tested for presence of HPV DNA by PCR. The incidence of tonsillar cancer increased 2.8‐fold (2.6 in men and 3.5 in women) from 1970 to 2002. During the same period, a significant increase in the proportion of HPV‐positive tonsillar cancer cases was observed, as it increased 2.9‐fold (p < 0.001). The distribution of HPV‐positive cases was 7/30 (23.3%) in the 1970s, 12/42 (29%) in the 1980s, 48/84 (57%) in the 1990s and 32/47 (68%) during 2000–2002. We have demonstrated a highly significant and parallel increase both in the incidence of tonsillar cancer and the proportion of HPV‐positive tumors. Hence, HPV may play an important role for the increased incidence of tonsillar cancer. This should definitely influence future preventive strategies as well as treatment for this type of cancer.

Human papillomavirus is a favourable prognostic factor in tonsillar cancer and its oncogenic role is supported by the expression of E6 and E7

From 1970 to 2002 in the Stockholm area, we revealed a parallel three‐fold increase in the incidence of tonsillar cancer and the proportion of human papillomavirus (HPV) positive tonsillar cancer cases, indicating a possible role of HPV infection in this disease. We have now examined whether HPV and viral load in pre‐treatment tonsillar cancer biopsies correlates to disease prognosis, and whether the presence of HPV‐16 E6 and E7 mRNA could be ascertained. The presence of HPV‐16, but not viral load, in tonsillar cancer was shown to be a favourable prognostic factor for clinical outcome. Moreover, E6 and/or E7 were expressed in almost all assessable HPV‐16 positive cases, supporting an oncogenic role of HPV‐16 in tonsillar cancer.

Human papillomavirus is more common in base of tongue than in mobile tongue cancer and is a favorable prognostic factor in base of tongue cancer patients

The frequency of human papilloma virus (HPV) and its influence on clinical outcome was analyzed retrospectively in pre‐treatment paraffin embedded biopsies from 110 patients with tongue cancer. The presence of HPV DNA was examined in 85 mobile tongue tumors and 25 base of tongue tumors by a polymerase chain reaction (PCR) with 2 general primer pairs, GP5+/6+ and CPI/IIG. When HPV‐DNA was found, HPV‐type specific primers and direct sequencing were used for HPV sub‐type verification. Twelve of 110 (10.9%) samples were HPV‐positive; 9 for HPV‐16, 1 for HPV‐33, 1 for HPV‐35 and 1 could not be analyzed because of shortage of DNA. HPV was significantly more common in base of tongue tumors (10/25, 40.0%) compared to tumors of the mobile tongue (2/85, 2.3%). The influence of HPV on clinical outcome in mobile tongue cancer could not be studied, due to that HPV was present in too few cases. Of the 19 patients with base of tongue cancer that were included in the survival analysis, however, 7 patients with HPV‐positive base of tongue cancer had a significantly favorable 5‐year survival rate compared to the 12 HPV‐negative patients. In conclusion, HPV is significantly more common in base of tongue cancer than in mobile tongue cancer, and has a positive impact on disease‐specific survival in patients with base of tongue cancer.

The incidence of tonsillar cancer in Sweden is increasing

Conclusions: The incidence of tonsillar cancer in Sweden is increasing, particularly among men. Risk factors other than smoking may have contributed to the observed secular trend in men. In women, however, smoking can be a part of the explanation. Further studies to look at changes in other environmental factors, such as human papilloma virus (HPV) infection, are clearly warranted. Objectives: Head and neck cancer is related to smoking habits and smoking has decreased substantially during the last 30 years in Sweden. However, there is suspicion that the incidence of tonsillar cancer has increased in the last 30 years as it has in the USA and Finland, in spite of reduced prevalence of known risk factors. The time trends of oral and oropharygeal cancer have been studied in Sweden, but not tonsillar cancer specifically. Subjects and methods: We used the Swedish Cancer Registry to assess the secular trend of incidence of tonsillar cancer in Sweden since 1960. For comparison we investigated the incidence of other oral cancers and lung cancer, which are also smoking-related. The prevalence of smoking was investigated for reference. Age-standardized incidence rates were calculated and linear regression was used to evaluate secular trends. Results: The incidence of tonsillar cancer increased by 2.6% per year in men and 1.1% in women. No similar increase was seen in the other oral cancers. For lung cancer there was a decrease in the incidence in men, but in women the incidence is still increasing.

Presence and influence of human papillomaviruses (HPV) in Tonsillar cancer.

Tonsillar cancer is the most common of the oropharyngeal carcinomas and human papillomavirus (HPV) has been found to be present in approximately half of all cases. Patients with HPV-positive tonsillar cancer have been observed to have a better clinical outcome than patients with HPV-negative tonsillar cancer. Moreover, patients with tonsillar cancer and a high viral load have been shown to have a better clinical outcome, including increased survival, compared to patients with a lower HPV load in their tumors. Recent findings show that HPV-positive tumors are not more radiosensitive and do not have fewer chromosomal aberrations than HPV-negative tumors, although some chromosomal differences may exist between HPV-positive and -negative tonsillar tumors. Current experimental and clinical data indicate that an active antiviral cellular immune response may contribute to this better clinical outcome. These data are also in line with the findings that the frequency of tonsillar cancer is increased in patients with an impaired cellular immune system. Thus, therapeutic and preventive HPV-16 antiviral immune vaccination trials may be worthwhile, not only in cervical cancer, but also in tonsillar cancer.

Disclosure of Incurable Illness to Spouses: Do They Want to Know? A Swedish Population-Based Follow-Up Study

PURPOSE Awareness of the cancer patients terminal state decreases the risk of psychological morbidity of the bereaved. We wanted to determine whether male spouses of cancer patients who died from their disease had received information that the illness was incurable and to determine their preferences of disclosure. PARTICIPANTS AND METHODS The study included 907 widowers whose wives had died of cancer. In an anonymous questionnaire, we asked whether the widower had received information that his wifes illness was incurable and about his attitudes towards receiving this information. RESULTS Six hundred ninety-one widowers (76%) participated. Eighty percent of the widowers reported that they were told [corrected] that the wifes cancer was incurable, and 21% reported that they had been informed within 1 week before the patients death. Although 14% of the widowers did not think the next of kin should be told immediately when the patients cancer is beyond cure, 39% of the men did not want the patient to be immediately informed. Furthermore, 71% of the men who were never informed about the incurable illness believed that the next of kin should receive that information immediately. CONCLUSION Although a large majority of men prefer an immediate disclosure about the incurable stage of their wifes illness, 41% of the husbands received this information during the last week of the patients life or not at all. These findings indicate that there is room for improvement in the level of communication between health providers and the husbands of women with incurable cancer.

Prevalence of Human Papillomavirus (HPV) in Oesophageal Squamous Cell Carcinoma in Relation to Anatomical Site of the Tumour

Background The prevalence and role of human papillomavirus (HPV) in the aetiology of oesophageal squamous cell carcinoma is uncertain. Based on the presence of HPV in the oral cavity and its causal association with squamous cell carcinoma of the oropharynx, we hypothesised that HPV is more strongly associated with proximal than distal oesophageal squamous cell carcinoma. Methods A population-based study comparing HPV infection in relation to tumour site in patients diagnosed with oesophageal squamous cell carcinomas in the Stockholm County in 1999–2006. Multiplex polymerase chain reaction genotyping (PCR) with Luminex was conducted on pre-treatment endoscopic biopsies to identify type specify HPV. Carcinogenic activity of HPV was assessed by p16INK4a expression. Multivariable logistic regression was used to calculate odds ratios and 95% confidence intervals. Results Among 204 patients, 20 (10%) had tumours harbouring HPV DNA, almost all (90%) of HPV high-risk type, mainly HPV16. Tumours containing HPV were not overrepresented in the upper compared to the middle or lower third of the oesophagus (odds ratio 0.6, 95% confidence interval 0.2–1.9). P16INK4a expression was similarly common (24% and 16%) in the HPV-positive and HPV-negative groups. Conclusion This study found a limited presence of HPV in oesophageal squamous cell carcinoma of uncertain oncogenic relevance and did not demonstrate that HPV was more strongly associated with proximal than distal tumours.

Risk factors and chemoprevention in Barrett's esophagus – an update

Abstract Objective. Barretts esophagus (BO) is a precursor of esophageal adenocarcinoma (OAC), a cancer with a poor prognosis and an increasing incidence. Hence there is an interest in mapping causal factors underlying BO and finding strategies to reduce the risk of dysplasia progression in patients with BO. Here we review current knowledge on established as well as less risk factors for the development of BO. Additionally, we summarize todays status on the use of chemoprevention aiming to reduce the risk of cancer progression in BO patients. Methods. We searched Medline and the Cochrane Library using the MeSH terms “Barretts esophagus” and “Barrett esophagus,” both alone and combined with the terms “risk factor,” “aetiology,” “diet,” or “prevention.” Focus was on original contributions, systematic reviews, and meta-analyses. Results. Established risk factors for the development of BO include gastro-esophageal reflux, obesity, male gender, Caucasian ethnicity, and increasing age. Smoking might increase the risk of BO, while aspirin/NSAIDs, Helicobacter pylori infection, and specific “healthy” dietary factors may lower the risk. The potential value of using chemoprevention with proton pump inhibitors, aspirin/NSAIDs, or statins is still uncertain. Conclusions. There is today a substantial knowledge of risk factors of BO. Certain diet may be protective of BO, albeit yet to be proven. The efficiency of chemoprevention in BO is currently addressed further in randomized clinical trials.

Whole-tissue biopsy phenotyping of three-dimensional tumours reveals patterns of cancer heterogeneity

Intratumoral heterogeneity is a critical factor when diagnosing and treating patients with cancer. Marked differences in the genetic and epigenetic backgrounds of cancer cells have been revealed by advances in genome sequencing, yet little is known about the phenotypic landscape and the spatial distribution of intratumoral heterogeneity within solid tumours. Here, we show that three-dimensional light-sheet microscopy of cleared solid tumours can identify unique patterns of phenotypic heterogeneity, in the epithelial-to-mesenchymal transition and in angiogenesis, at single-cell resolution in whole formalin-fixed paraffin-embedded (FFPE) biopsy samples. We also show that cleared FFPE samples can be re-embedded in paraffin after examination for future use, and that our tumour-phenotyping pipeline can determine tumour stage and stratify patient prognosis from clinical samples with higher accuracy than current diagnostic methods, thus facilitating the design of more efficient cancer therapies.A method that identifies patterns of tumour heterogeneity in intact biopsy samples using 3D light-sheet microscopy stratifies patients by tumour stage.