Johan Lindholm

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.

Evidence of the Oncologic Superiority of Cylindrical Abdominoperineal Excision for Low Rectal Cancer

PURPOSE Abdominoperineal excision (APE) of the rectum and anus for rectal cancer continues to have greater local recurrence and poorer survival than that seen following anterior resection. Changing to an extended prone perineal dissection results in a more cylindrical specimen and should improve outcomes. PATIENTS AND METHODS One hundred twenty-eight specimens from patients who underwent APE that was performed for potentially curable primary rectal adenocarcinoma were dissected according to standard protocol in Leeds and Stockholm between 1997 and 2007 and were studied. Tissue morphometry was performed on the cross sectional photographs of 93 patient cases. RESULTS The cylindrical technique removed more tissue in the distal rectum and in all slices that contained tumor compared with the standard operation (both P < .0001). Greater distance was observed from the muscularis propria or internal sphincter to the anterior, posterior, and lateral resection margins (all P < .0001). This was associated with lower circumferential resection margin (CRM) involvement (14.8% v 40.6%; P = .013) and intraoperative perforations (3.7% v 22.8%; P = .0255). An increase in the amount of tissue removed in the distal rectum (P < .0001) was demonstrated by a single surgeon who changed from the standard to the cylindrical technique during the study period; the change was associated with a reduction in CRM positivity (from 36.2% to 12.5%) and in perforations (from 12.8% to 0.0%). CONCLUSION Cylindrical APE performed in the prone position for low rectal cancer removes more tissue around the tumor that leads to a reduction in CRM involvement and intraoperative perforations, which should reduce local disease recurrence. The cylindrical technique has the potential to improve patient outcomes substantially if appropriate surgical education programs are developed.

Human papillomavirus type 16 is episomal and a high viral load may be correlated to better prognosis in tonsillar cancer

The aim of our study was to investigate the physical state and the viral load of HPV‐16 in tonsillar cancer and to correlate these findings with clinical outcome. To distinguish between integrated and episomal forms of HPV, 22 fresh‐frozen tonsillar cancer samples were analysed by a method based on restriction enzyme cleavage, ligation and PCR (rliPCR). HPV‐16 was detected in 11/22 and HPV‐33 in 1/22 of the cancers, hence 12/22 (55%) of the tumours were HPV positive. Only extrachromosomal forms of HPV‐16 were observed. Full‐length episomal HPV was detected exclusively in 7/11 of the cancers, whereas both full‐length and deleted forms of episomal HPV‐16 were found in parallel in 2 other tumours. In 1 tumour only a deleted episomal form of HPV‐16 was present. In the remaining HPV‐16 positive tumour both full‐length episomal as well as an 11 kbp PCR product were detected and if the 11 kbp product contained integrated HPV, or was off‐size linearised episomal could not be determined. In 2 cervical cancer controls, HPV‐16 was integrated and could be chromosome located. HPV‐16 was quantified by real‐time PCR and most tonsillar cancers contained between 10 to a few hundred copies of HPV per β‐actin. The 6 patients with tumour sections with ≥190 HPV‐16 copies/β‐actin remained tumour free (p = 0.026) and had a better survival rate (p = 0.039) when compared to the 5 patients with tumours sections with ≤60 HPV‐16 copies/β‐actin. In conclusion, HPV‐16 is mainly episomal in tonsillar cancer. The viral load showed a wide distribution and the clinical outcome in our study was better when the HPV load was higher.

The role of human papillomavirus in the increased incidence of base of tongue cancer

Numerous reports have shown that the incidence for oropharyngeal cancer is increasing and that human papillomavirus (HPV) is a risk factor. However, few studies have investigated the specific subsites of the oropharynx. Following our previous research on tonsillar cancer, we assessed the increase in the incidence of base of tongue cancer and the prevalence of HPV in this disease. Between 1998 and 2007, 109 patients were diagnosed for base of tongue cancer in Stockholm county. Ninety‐five paraffin‐embedded diagnostic tumor biopsies from patients were obtained and tested for HPV, both by general HPV PCR and HPV‐16/HPV‐33 type‐specific PCR. Expression of HPV‐16 RNA was analyzed to confirm E6 and/or E7 expression. Incidence data were obtained from the Swedish Cancer Registry. An overall increase in the incidence of base of tongue cancer from 0.15/100,000 person‐years during 1970–1974 to 0.47/100,000 person‐years during 2005–2007 was found in Sweden. The prevalence of HPV in base of tongue cancer in Stockholm county increased from 58% during 1998–2001 to 84% during 2004–2007 (p < 0.05). In the HPV‐positive tumors, HPV‐16 dominated (86%) but interestingly, HPV33 was detected in as many as 10%. E6 and/or E7 RNA were found in 85% of the samples tested. The incidence of base of tongue cancer, as well as the proportion of HPV‐positive tumors, has increased in Sweden during the study period, suggesting that HPV may contribute to this increase.

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.

Fecal calprotectin: a quantitative marker of colonic inflammation in children with inflammatory bowel disease.

Objectives: The protein calprotectin (S100 A8/A9) is present in neutrophils, monocytes, and macrophages. Colorectal inflammation can be detected by increased excretion of fecal calprotectin (FC). The aim of this study was to evaluate FC as a quantitative marker of inflammatory activity in children with inflammatory bowel disease (IBD). Patients and Methods: Thirty-nine children with IBD delivered a fecal spot sample and underwent colonoscopy. The samples were examined with an enzyme-linked immunosorbent assay for FC (Calprest, Eurospital, Trieste, Italy). The concentrations were correlated to macroscopic and microscopic assessments of extent and severity of inflammation in 8 colonic segments for each patient. Results: FC correlated significantly to the macroscopic extent (Spearman ρ = 0.61) and the severity (Spearman ρ = 0.52) of colonic inflammation and to a macroscopic, combined extent and severity score (Spearman ρ = 0.65). Significant correlations also were found to the microscopic extent (Spearman ρ = 0.71) and severity (Spearman ρ = 0.72) of colonic inflammation and to a microscopic, combined extent and severity score (Spearman ρ = 0.75). The median FC was 392 μg/g (95% confidence interval [CI], 278–440) in children with clinical IBD symptoms (n = 23) and 32.9 μg/g (95% CI, 9.4–237) in asymptomatic IBD patients (n = 16). Of the asymptomatic children, 56% had a complete microscopic mucosal healing, and their median FC was 9.9 μg/g (95% CI, 5.9–41.9). Conclusions: FC can be used as a surrogate marker for estimation of colonic inflammation in pediatric IBD. Normalized FC concentration seems to indicate complete mucosal healing. FC is simple to obtain and analyze; this should facilitate objective assessment and monitoring of IBD activity.

Comparative genomic hybridization analysis of tonsillar cancer reveals a different pattern of genomic imbalances in human papillomavirus‐positive and ‐negative tumors

Our aim was to map and compare genomic imbalances in human papillomavirus (HPV)‐positive and ‐negative squamous cell carcinomas of the tonsil. Twenty‐five primary carcinomas were analyzed by comparative genomic hybridization. Fifteen (60%) were found to be HPV‐positive by PCR, and the majority were HPV‐16. There were statistically significant differences in the distribution of DNA gains and losses between the HPV‐positive and ‐negative samples. Eleven of 15 HPV‐positive samples (73%) showed gain on chromosome 3q24‐qter, while only 4/10 (40%) HPV‐negative samples had the same gain (p = 0.049). Furthermore, 4/10 (40%) HPV‐negative samples but no HPV‐positive samples had gain on chromosome 7q11.2‐q22 (p = 0.017). As expected, and similar to previous studies, patients with an HPV‐positive tumor had a statistically significantly better disease‐specific survival than patients with an HPV‐negative tumor (p = 0.002). The most common changes, e.g., gain on 3q or 8q, loss on 11q or 13 and loss on chromosome 7q in HPV‐negative tumors, did not have any influence on prognosis. However the number of cases in each subgroup was limited.

Low risk of recurrence of enchondroma and low-grade chondrosarcoma in extremities. 80 patients followed for 2-25 years.

We analyzed the clinical course in 40 patients with enchondroma and 40 with low-grade chondrosarcoma of the extremities after a median follow-up of 7 years. 13 patients with enchondroma and 2 with chondrosarcoma had only open biopsy and they had no signs of further progression of the lesions. Among 23 patients with enchondroma and 23 with chondrosarcoma who were treated by intralesional curettage, 3 had local recurrences. The 10-year local recurrence rate was 0.04 in the enchondroma group and 0.09 in the chondrosarcoma group. There were no metastases. The results imply that enchondroma and low-grade chondrosarcoma of the extremities should be treated with limited surgery. The morbidity associated with en bloc resection and reconstruction can apparently be obviated without jeopardizing the limb or survival.