Efficacy of Electrochemotherapy in Breast Cancer Patients of Different Receptor Status: The INSPECT Experience

Electrochemotherapy has been proven to be an efficient treatment for cutaneous metastases of various cancers. Data on breast cancer (BC) patients with cutaneous metastases were retrieved from the INSPECT database. Patients were divided by their receptor status: HER2+, HR+ (ER/PgR+), and TN (triple negative). Groups were similar for histological subtype and location of the nodules. Most patients were previously treated with surgery/systemic therapy/radiotherapy. We found no differences in the three groups in terms of response ratio (OR per patient 86% HER2+, 80% HR+, 76% TN, p = 0.8664). The only factor positively affecting the complete response rate in all groups was small tumor size (<3 cm, p = 0.0105, p = 0.0001, p = 0.0266, respectively). Local progression-free survival was positively impacted by the achievement of complete response in HER2+ (p = 0.0297) and HR+ (p = 0.0094), while overall survival was affected by time to local progression in all groups (p = 0.0065 in HER2+, p < 0.0001 in HR+, p = 0.0363 in TN). ECT treatment is equally effective among groups, despite different receptor status. Response and local tumor control seem to be better in multiple small lesions than in big armor-like lesions, suggesting that treating smaller, even multiple, lesions at the time of occurrence is more effective than treating bigger long-lasting armor-like cutaneous lesions.

Bleomycin electrosclerotherapy (BEST) for the treatment of vascular malformations. An International Network for Sharing Practices on Electrochemotherapy (InspECT) study group report

BACKGROUND

Biomedical applications of electroporation are expanding out of the field of oncology into vaccination, treatment of arrhythmias and now in the treatment of vascular malformations. Bleomycin is a widely used sclerosing agent in the treatment of various vascular malformations. The application of electric pulses in addition to bleomycin enhances the effectiveness of the drug, as demonstrated by electrochemotherapy, which utilizes bleomycin in the treatment of tumors. The same principle is used in bleomycin electrosclerotherapy (BEST). The approach seems to be effective in the treatment of low-flow (venous and lymphatic) and, potentially, even high-flow (arteriovenous) malformations. Although there are only a few published reports to date, the surgical community is interested, and an increasing number of centers are applying BEST in the treatment of vascular malformations. Within the International Network for Sharing Practices on Electrochemotherapy (InspECT) consortium, a dedicated working group has been constituted to develop standard operating procedures for BEST and foster clinical trials.

CONCLUSIONS

By treatment standardization and successful completion of clinical trials demonstrating the effectiveness and safety of the approach, higher quality data and better clinical outcomes may be achieved.

European e-Delphi process to define expert consensus on electrochemotherapy treatment indications, procedural aspects, and quality indicators in melanoma

BACKGROUND

Skin metastases are an important co-morbidity in melanoma. Despite broad adoption, electrochemotherapy implementation is hindered by a lack of treatment indications, uncertainty regarding procedural aspects, and the absence of quality indicators. An expert consensus may harmonize the approach among centres and facilitate comparison with other therapies.

METHODS

An interdisciplinary panel was recruited for a three-round e-Delphi survey. A literature-based 113-item questionnaire was proposed to 160 professionals from 53 European centres. Participants rated each item for relevance and degree of agreement on a five-point Likert scale, and received anonymous controlled feedback to allow revision. The items that reached concordant agreement in two successive iterations were included in the final consensus list. In the third round, quality indicator benchmarks were defined using a real-time Delphi method.

RESULTS

The initial working group included 122 respondents, of whom 100 (82 per cent) completed the first round, thus qualifying for inclusion in the expert panel (49 surgeons, 29 dermatologists, 15 medical oncologists, three radiotherapists, two nurse specialists, two clinician scientists). The completion rate was 97 per cent (97 of 100) and 93 per cent (90 of 97) in the second and third rounds respectively. The final consensus list included 54 statements with benchmarks (treatment indications, (37); procedural aspects, (1); quality indicators, (16)).

CONCLUSION

An expert panel achieved consensus on the use of electrochemotherapy in melanoma, with a core set of statements providing general direction to electrochemotherapy users to refine indications, align clinical practices, and promote quality assurance programmes and local audits. The residual controversial topics set future research priorities to improve patient care.

The development and validation of a decision aid to facilitate patient choice of surgery versus radiotherapy for high-risk basal cell carcinoma

Basal cell carcinoma (BCC) is an increasingly common cancer. For high-risk BCCs, there are several treatment options, with similar efficacies. The current best practice in deciding upon a particular treatment is for a patient-centred approach. At present, there are few resources available for patients to assist their choice. This reduces patient autonomy and increases the burden on clinicians within clinic. Patient decision aids (PDAs) have been shown to increase patient autonomy and facilitate shared decision-making. Currently, there is no published PDA designed to facilitate the decision between surgical management or radiotherapy in high-risk BCCs. We developed a novel decision aid designed along the International Patient Decision Aid Standards to fill this clinical need, and evaluated its acceptance by both patients and clinicians. We describe the challenges faced at initial alpha and subsequent beta testing, and go on to validate our PDA with both the Decisional Conflict Scale and the nine-item Shared Decision Making Questionnaire (SDMQ9). We include an example of the PDA and encourage other units to modify the PDA for their own use.

National audit of non-melanoma skin cancer excisions performed by plastic surgery in the UK

A national, multi-centre audit of non-melanoma skin cancer excisions by plastic surgery.

Electrochemotherapy for the treatment of cutaneous squamous cell carcinoma: The INSPECT experience (2008-2020)

Introduction

Cutaneous squamous cell carcinoma (cSCC) is a frequent skin cancer with a high risk of recurrence characterized by tumor infiltration and, in advanced cases, a poor prognosis. ECT (electrochemotherapy) is an alternative treatment option for locally advanced or recurrent cSCC that is unsuitable for surgical resection. In this study, we aimed to evaluate the data in the InspECT (International Network for Sharing Practice on ECT) registry of the referral centers and to clarify the indications for the use of ECT as a treatment modality for cSCC.

Materials and methods

Patients with primary, recurrent or locally advanced cSCC from 18 European centers were included. They underwent at least one ECT session with bleomycin between February 2008 and November 2020, which was performed following the European Standard Operating Procedures.

Results

The analysis included 162 patients (mean age of 80 years; median, 1 lesion/patient). Side effects were mainly local and mild (hyperpigmentation, 11%; ulceration, 11%; suppuration, 4%). The response to treatment per patient was 62% complete and 21% partial. In the multivariate model, intravenous drug administration and small tumor size showed a significant association with a positive outcome (objective response). One-year local progression-free survival was significantly better (p<0.001) in patients with primary tumors (80% (95% C.I. 70%-90%) than in patients with locally advanced disease (49% (95% C.I. 30%-68%).

Conclusion

In the present study, ECT showed antitumor activity and a favorable safety profile in patients with complex cSCC for whom there was no widely accepted standard of care. Better results were obtained in primary and small tumors (<3 cm) using intravenous bleomycin administration.

Treatment of Basal Cell Carcinoma with Electrochemotherapy: Insights from the InspECT Registry (2008–2019)

This prospective registry-based study aims to describe electrochemotherapy (ECT) modalities in basal cell carcinoma (BCC) patients and evaluate its efficacy, safety, and predictive factors. The International Network for Sharing Practices of Electrochemotherapy (InspECT) multicentre database was queried for BCC cases treated with bleomycin-ECT between 2008 and 2019 (n = 330 patients from seven countries, with 623 BCCs [median number: 1/patient; range: 1–7; size: 13 mm, range: 5–350; 85% were primary, and 80% located in the head and neck]). The procedure was carried out under local anaesthesia in 68% of cases, with the adjunct of mild sedation in the remaining 32%. Of 300 evaluable patients, 242 (81%) achieved a complete response (CR) after a single ECT course. Treatment naïvety (odds ratio [OR] 0.35, 95% confidence interval [C.I.] 0.19–0.67, p = 0.001) and coverage of deep tumour margin with electric pulses (O.R. 5.55, 95% C.I. 1.37–21.69, p = 0.016) predicted CR, whereas previous radiation was inversely correlated (O.R. 0.25, p = 0.0051). Toxicity included skin ulceration (overall, 16%; G3, 1%) and hyperpigmentation (overall, 8.1%; G3, 2.5%). At a 17-month follow-up, 28 (9.3%) patients experienced local recurrence/progression. Despite no convincing evidence that ECT confers improved outcomes compared with standard surgical excision, it can still be considered an opportunity to avoid major resection in patients unsuitable for more demanding treatment. Treatment naïvety and coverage of the deep margin predict tumour clearance and may inform current patient selection and management.

Health-related quality of life trajectories in melanoma patients after electrochemotherapy: real-world insights from the InspECT register

BACKGROUND

Electrochemotherapy (ECT) effectively controls skin metastases from cutaneous melanoma.

OBJECTIVES

This study aimed to evaluate health-related quality of life (HRQoL) in melanoma patients pre-/post-ECT and its effect on treatment outcome.

METHODS

The analysis included prospective data from the International Network for Sharing Practices of ECT register. Following the Standard Operating Procedures, patients received intravenous or intratumoural bleomycin (15,000 IU/m2 ; 1000 IU mL/cm3 ) followed by 100-microsecond, 1000-V/cm electric pulses. Endpoints included response (RECIST v3.0), local progression-free survival (LPFS), toxicity (CTCAE v5.0), and patient-reported HRQoL at baseline, one, two, four and ten months (EuroQol [EQ-5D-3L], including 5-item utility score [EQ-5D] and visual analogue scale for self-reported health state [EQ-VAS]). Comparisons within/between subgroups were made for statistical and minimal important differences (MID). HRQoL scores and clinical covariates were analysed to identify predictors of response in multivariate analysis.

RESULTS

Median tumour size was 2 cm. Complete response rate, G3 toxicity and one-year LPFS in 378 patients (76% of the melanoma cohort) were 47%, 5%, and 78%. At baseline, age-paired HRQoL did not differ from the general European population. Following ECT, both EQ-5D and EQ-VAS scores remained within MID boundaries, particularly among complete responders. A subanalysis of the EQ-5D items revealed a statistically significant deterioration in pain/discomfort and mobility (restored within four months), and self-care and usual activities (throughout the follow-up) domains. Concomitant checkpoint inhibition correlated with better EQ-5D and EQ-VAS trajectories. Baseline EQ-5D was the exclusive independent predictor for complete response (RR 14.76, p=0.001).

CONCLUSIONS

HRQoL of ECT melanoma patients parallels the general population and is preserved in complete responders. Transient deterioration in pain/discomfort and mobility and persistent decline in self-care and usual activities may warrant targeted support interventions. Combination with checkpoint inhibitors is associated with better QoL outcomes. Baseline HRQoL provides predictive information which can help identify patients most likely to respond.

Prospektive Kohortenstudie von InspECT zur Sicherheit und Wirksamkeit der Elektrochemotherapie bei Hauttumoren und Metastasen in Abhängigkeit von Ulzeration

HINTERGRUND

Elektrochemotherapie (ECT) ist eine wirksame lokale Behandlung von Hauttumoren. Ziel dieser Studie war es, die Wirksamkeit der ECT bei ulzerierten gegenüber nichtulzerierten Tumoren zu vergleichen und den Effekt auf tumorassoziierte Symptome zu untersuchen.

METHODIK

20 Krebszentren des International Network for Sharing Practices on Electrochemotherapy (InspECT) sammelten prospektiv Daten. Die ECT wurde nach dem ESOPE-Protokoll durchgeführt. Das Therapieansprechen wurde anhand der Entwicklung der Läsionsgröße bewertet. Zusätzlich wurden Schmerzen, Symptome, Leistungsstatus (ECOG-Index) und Gesundheitszustand (EQ-5D-Fragebogen) untersucht.

ERGEBNISSE

716 Patienten mit ulzerierten (n = 302) und nichtulzerierten (n = 414) Hauttumoren und Metastasen wurden eingeschlossen (Mindest-Nachsorge 45 Tage). Nicht-ulzerierte Läsionen sprachen besser auf die ECT an als ulzerierte Läsionen (vollständiges Ansprechen: 65 % gegenüber 51 %, p = 0,0061). Nur 38 % (115/302) der Patienten mit ulzerierten Läsionen vor der ECT wiesen bei der letzten Nachuntersuchung ulzerierte Läsionen auf. Patienten mit ulzerierten Läsionen berichteten über stärkere Schmerzen und schwerere Symptome im Vergleich zu Patienten mit nichtulzerierten Läsionen, die sich nach der ECT signifikant und kontinuierlich besserten. Bei Patienten mit nichtulzerierten Läsionen hingegen nahmen die Schmerzen während der Behandlung vorübergehend zu. Es wurden keine schwerwiegenden Nebenwirkungen beobachtet.

SCHLUSSFOLGERUNGEN

Die ECT ist eine sichere und wirksame lokale Behandlung von Hauttumoren. Während die ECT die Symptome insbesondere bei Patienten mit ulzerierten Läsionen verbessert, sollte auf Basis der Daten die Implementation eines perioperativen Schmerzmanagements besonders bei nichtulzerierten Läsionen während der ECT erwogen werden.

Prospective cohort study by InspECT on safety and efficacy of electrochemotherapy for cutaneous tumors and metastases depending on ulceration

BACKGROUND

Electrochemotherapy (ECT) is an effective local treatment for cutaneous tumors. The aim of this study was to compare the effectiveness of ECT in ulcerated vs. non-ulcerated tumors and investigate the effect on tumor-associated symptoms.

METHODS

Twenty cancer centers in the International Network for Sharing Practices on Electrochemotherapy (InspECT) prospectively collected data. ECT was performed following ESOPE protocol. Response was evaluated by lesion size development. Pain, symptoms, performance status (ECOG-Index) and health status (EQ-5D questionnaire) were evaluated.

RESULTS

716 patients with ulcerated (n = 302) and non-ulcerated (n = 414) cutaneous tumors and metastases were included (minimum follow-up of 45 days). Non-ulcerated lesions responded to ECT better than ulcerated lesions (complete response 65 % vs. 51 %, p = 0.0061). Only 38 % (115/302) with ulcerated lesions before ECT presented with ulcerated lesions at final follow-up. Patients with ulcerated lesions reported higher pain and more severe symptoms compared to non-ulcerated lesions, which significantly and continuously improved following ECT. In non-ulcerated lesions however, pain spiked during the treatment. No serious adverse events were reported.

CONCLUSIONS

ECT is a safe and effective local treatment for cutaneous tumors. While ECT improves symptoms especially in patients with ulcerated lesions, data suggest the implementation of a perioperative pain management in non-ulcerated lesions during ECT.

Dermatofibrosarcoma protuberans (DFSP) arising from a keloid scar - A case report

Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous sarcoma with an indolent early course that may be misdiagnosed for benign skin pathology. In this case-report we highlight an instance of DFSP arising from a keloid scar de novo and present a reconstruction with a local pedicled LD flap. We subsequently appraise the related literature and discuss the diagnostic challenges.

Updated standard operating procedures for electrochemotherapy of cutaneous tumours and skin metastases

Electrochemotherapy is now in routine clinical use to treat cutaneous metastases of any histology, and is listed in national and international guidelines for cutaneous metastases and primary skin cancer. Electrochemotherapy is used by dermatologists, surgeons, and oncologists, and for different degrees and manifestations of metastases to skin and primary skin tumours not amenable to surgery. This treatment utilises electric pulses to permeabilize cell membranes in tumours, thus allowing a dramatic increase of the cytotoxicity of anti-cancer agents. Response rates, often after only one treatment, are very high across all tumour types. The most frequent indications are cutaneous metastases from malignant melanoma and breast cancer. In 2006, standard operating procedures (SOPs) were written for this novel technology, greatly facilitating introduction and dissemination of the therapy. Since then considerable experience has been obtained treating a wider range of tumour histologies and increasing size of tumours which was not originally thought possible. A pan-European expert panel drawn from a range of disciplines from dermatology, general surgery, head and neck surgery, plastic surgery, and oncology met to form a consensus opinion to update the SOPs based on the experience obtained. This paper contains these updated recommendations for indications for electrochemotherapy, pre-treatment information and evaluation, treatment choices, as well as follow-up.

Electrochemotherapy of unresectable cutaneous tumours with reduced dosages of intravenous bleomycin: analysis of 57 patients from the International Network for Sharing Practices of Electrochemotherapy registry

BACKGROUND

Electrochemotherapy (ECT) is currently used to treat unresectable superficial tumours of different histotypes through the combination of cytotoxic chemotherapy and local application of electric pulses. In 2006, a collaborative project defined the ESOPE (European Standard Operating Procedures of Electrochemotherapy) guidelines to standardize the procedure. The International Network for Sharing Practices of Electrochemotherapy (InspECT) aims to refine the ESOPE and improve clinical practice. Limiting patient exposure to systemic chemotherapy would be advisable to ameliorate ECT safety profile.

OBJECTIVE

The aim of this study was to evaluate the efficacy and toxicity of ECT with reduced chemotherapy dosages.

METHODS

In a retrospective analysis of a prospectively maintained database (InspECT registry), we evaluated the outcome of patients who received ECT with reduced dosages of bleomycin (7500, 10 000 or 13 500 IU/m² , instead of the standard dose of 15 000 IU/m² ). Tumour response in melanoma patients was compared with melanoma patients of the InspECT registry who received the standard dose of bleomycin.

RESULTS

We identified 57 patients with 147 tumours (melanoma, 38.6%; squamous cell carcinoma, 22.8%; basal cell carcinoma, 17.5%; breast cancer 7%; Kaposi sarcoma 7%; other histotypes, 7.1%). Per-tumour complete response (CR) rate at 60 days was 70.1% (partial, 16.3%); per-patient CR was 57.9% (partial, 21.1%). Local pain was the most frequently reported side-effect (n = 22 patients [39%]), mostly mild; two patients experienced flu-like symptoms, one patient nausea. We observed the same CR rate (55%) in patients with melanoma treated by reduced or conventional bleomycin dosages (P = 1.00).

CONCLUSIONS

Electrochemotherapy performed with reduced bleomycin dosages could be as effective as with currently recommended dose. Patients with impaired renal function or candidate to multiple ECT cycles could benefit from a reduced dose protocol. Our findings need prospective confirmation before being adopted in clinical practice.

Is sentinel lymph node biopsy warranted for desmoplastic melanoma? A systematic review

BACKGROUND

Desmoplastic melanoma (DM) is an uncommon malignancy associated with a high local recurrence rate. The aim of this systematic review was to determine the positivity rate of sentinel lymph node biopsy (SLNB) in patients with DM. The secondary outcome was to establish if SLNB is warranted for both pure DM (PDM) and mixed DM (MDM).

METHODS

A full systematic literature review of SLNB in DM was performed by two authors in January 2016. Ovid MEDLINE, Ovid EMBASE and the Cochrane Central Register of Controlled Trials were searched.

RESULTS

Sixteen studies involving 1519 patients having SLNB in DM were included, of which 99 patients had positive SLNB (6.5%). Two articles reported a significantly reduced disease-free survival (DFS) with positive SLNB and three published a reduced melanoma-specific survival (MSS). Six studies compared SLNB in MDM and PDM. Of the 275 patients, 38 (13.8%) had a positive SLNB in MDM compared to 17 of 313 patients (5.4%) with positive SLNB in PDM.

CONCLUSIONS

Rates of positive SLNB in DM are reduced compared to other variants of melanoma; however, nodal status may still predict DFS and MSS. MDM is associated with a higher rate of micro-metastases to regional lymph nodes than PDM, and DFS and MSS may be lesser in MDM than in PDM. We would recommend the consideration of SLNB in MDM. However, with such low rates of positive SLNB in PDM, and in the absence of high-risk features to stratify patients, we would not recommend SLNB in PDM.

Predicting patients at risk for pain associated with electrochemotherapy

BACKGROUND

Electrochemotherapy describes the use of electric pulses to enhance chemotherapy uptake, and has proven highly efficient in treating cutaneous metastases. Patients referred for electrochemotherapy present with diverse clinical pictures, from multiple small lesions to large, ulcerated lesions. Post-electrochemotherapy pain has been observed in some patients. The objectives of this study were to evaluate pain scores before and after electrochemotherapy, and to investigate if patients at risk of post-procedure pain could be identified.

METHODS

Seven cancer centres in the International Network for Sharing Practices on Electrochemotherapy (INSPECT) consecutively and prospectively reported to a common database. Electrochemotherapy consisted of intratumoural or intravenous injection of bleomycin, followed by delivery of electric pulses in local or general anesthesia.

RESULTS

Of 121 patients 39% had metastatic melanoma, 18% squamous cell carcinoma, 16% breast cancer, 13% basal-cell carcinoma, and 14% other malignancies. Median size of the largest nodules was 2.3 cm (range 0.3-40 cm). A majority of patients presented with low pain scores, and this continued through follow-up (74%). A subset of patients had moderate (13%) or severe pain (13%) after treatment. Post-procedure pain was statistically significantly associated with: 1) moderate or severe pain before treatment (p<0.0001); 2) size of the largest treated lesion (p<0.01); 3) previous irradiation (p<0.02); and 4) high treatment current value (p<0.0001).

CONCLUSION

The majority of patients had no or mild pain after electrochemotherapy. Patients at risk for post-procedure pain could be identified at the pre-treatment visit, and/or at the time of treatment, enabling a pain management strategy for this group.

Perforator flaps in head and neck reconstruction

Free tissue transfer has revolutionized the management of complex head and neck defects. Perforator flaps represent the most recent advance in the development of free flap surgery. These flaps are based on perforating vessels and can be harvested without significant damage to associated muscles, thereby reducing the postoperative morbidity associated with muscle-based flaps. Elevation of perforator flaps requires meticulous technique and can be more challenging than raising muscle-based flaps. Use of a Doppler device enables reliable identification of the perforating vessels and aids in the design of free-style free flaps, where the flaps are designed purely according to the perforator located. The major advantage of free-style free flaps is that an unlimited number of flaps can potentially be designed on much shorter pedicles. The anterolateral thigh flap is the most commonly used perforator flap in head and neck reconstruction. Its use is described in detail, as is use of other less common perforator flaps. This article also describes head and neck reconstruction in a region-specific manner and gives a short-list of suitable flaps based on the location of the defect.

Pinnaplasty: reshaping ears to improve hearing aid retention

The hearing aid is extremely important to the deaf. A small number have difficulty in retaining the device because the ear is prominent or cup-shaped. This report describes 11 children whose ear shape was modified to improve hearing aid retention and one adult in whom an over set back ear was released to allow fitment of a postaural device. In eight of the 11 children treated, conservative measures such as double-sided tape and retention bands (Huggies) had been tried previously without success. The creation of an antihelical fold in a misshapen ear lacking such a fold provides a reinforcing strut which is useful to support a hearing aid. In patients whose ear had been excessively tethered by previous surgery, projection was restored by inserting a cartilage block behind the ear. In one child with ears tethered by previous surgery, costal cartilage was used not only to release both ears, but also to reconstruct a new helical rim on one side. Surgery enabled a normal postaural hearing aid to be worn in 17 of the 19 ears treated. The two failures deserve special mention. In one patient with a unilateral deformity and severe mental retardation, the dressings were pulled off immediately after surgery. In another patient with a bilateral problem, the appearance and hearing aid retention was improved, but there was not enough room in the postauricular sulcus on one side for the battery component to fit comfortably and an in-the-ear device is now used on that side. Pinnaplasty is a helpful strategy to improve hearing aid retention. Care must be taken not to overdo the set back so that enough room is left to retain the hearing device.

Effect of Imidazole on the Solubility of a His-Tagged Antibody Fragment

A number of studies have demonstrated the limited solubility of single-chain Fv antibody fragments and its improvement by genetic engineering. This limits the stability of recombinant protein upon storage and the efficiency of chemical modification. The RAFT3 scFv used in the present work is specific for melanoma-associated proteoglycan and an attractive candidate for clinical radioimaging studies because of its unusual radiolabelling properties. However, when expressed with a c-terminal his(6) IMAC purification tag, the recombinant protein starts to precipitate after column elution and dialysis against PBS and reaches a concentration of soluble protein of approximately 150 microg/mL within a few days upon storage at 4 degrees C. We tested several commonly used buffer modifications (addition of detergents, high salt, amino acids) to improve the solubility and stability of the protein but without any major improvement. However, we found that, when the final dialysis step was omitted and the protein left in IMAC column elution buffer (PBS containing imidazole), it remained soluble. Furthermore, several months old and precipitated protein could be redissolved in this buffer without loss of antigen binding. This observation and the largely pH-independent nature of protein solubility suggest that neither salt bridges formed by the his(6) tail nor cross-linking of his(6) tails mediated by metal ions leached from the column during elution are responsible for the limited solubility of the protein in the absence of imidazole. The presence of imidazole did not interfere with radiolabelling and in vivo tumor targeting in a mouse model. The solubilizing and stabilizing effect of imidazole could be of use for his(6) tagged and poorly soluble recombinant proteins other than scFvs.

Reducing renal accumulation of single-chain Fv against melanoma-associated proteoglycan by coadministration of L-lysine

In view of the rising melanoma incidence and the absence of effective treatments for metastatic disease, there is an urgent need for new methods that allow the early detection of melanoma. To this end, in vivo detection by patient imaging with single-chain Fv (scFv) antibody fragments is an attractive diagnostic approach. However, high non-specific accumulation of scFvs in the kidney reduces image quality in this body area and prevents the use of scFvs for melanoma radioimmunotherapy. We have tested the effect of coadministration of L-lysine with (125)I-labelled scFvs against melanoma-associated proteoglycan on kidney accumulation in a nude mouse xenograft model. Coadministration of L-lysine had no significant effect on tumour accumulation of scFvs or blood clearance, but decreased kidney accumulation by factors of 2.25, 2.3, 6.3 and 5.8, respectively, at 1, 3, 6 and 18 h post-injection, and improved tumour to muscle contrast. The reduction in kidney accumulation was maximal at time points that can be extrapolated to patient studies. The time dependence of the effect suggests that further improvements could be achieved with an optimized dosing regimen. When combined with other strategies to reduce kidney accumulation of scFvs, coadministration of L-lysine has the potential to significantly improve tumour to kidney contrast.

Improved production by domain inversion of single-chain Fv antibody fragment against high molecular weight proteoglycan for the radioimmunotargeting of melanoma

Melanoma is among the few cancers with rising incidence. Currently there is no effective treatment for metastatic disease, but improved detection of melanoma has the potential to benefit the management of patients with early disease. Radioimmunodection by imaging with single-chain Fv (scFv) antibody fragments is one such emerging diagnostic method. However, the amount of scFv that can be produced at a scale suitable for use in patients is limiting. We have previously shown that the bacterial expression of a scFv derived from a monoclonal antibody (MAb) specific for melanoma-associated proteoglycan can be increased by light chain shuffling. In this report we show that a further increase in expression yield can be obtained by reversing the usual V(H)-V(L) orientation of scFvs to V(L)-V(H). Such seemingly minor changes have previously been reported to have unexpected effects on the in vitro and in vivo binding properties of recombinant antibodies. Our results show that reversal of the V domain orientation of the scFv improves expression by 150% without an adverse effect on melanoma binding in vitro and tumor targeting in vivo. Therefore, our results show that alteration of V domain orientation can improve the production yield of clinically useful antibody fragments. When used in combination with other antibody engineering approaches for increased antibody production changing the domain orientation is a simple strategy to achieve significant improvements in the production of scFvs for tumor radioimmunodetection for patient studies.

Laser depilation of the natal cleft--an aid to healing the pilonidal sinus

BACKGROUND

Pilonidal disease is common. Excessive hair growth in the natal cleft is thought to be a factor in initiating these sinuses. It is chronic and intermittent in nature and treatment can be difficult. Hair removal by shaving or use of creams is often advised as a compliment to surgical treatments. However, access to the natal cleft can be difficult. Laser removal of hair in the natal cleft is considered as an aid to healing the pilonidal sinus.

PATIENTS AND METHODS

Over a 5-year period, 14 patients with recurrent pilonidal disease were treated in our unit with laser depilation. They were all contacted by postal questionnaire, and those with ongoing disease were asked to return to the clinic for evaluation and possible further treatment.

RESULTS

All patients returned the postal questionnaire. Of the 14 patients, 4 had on-going disease and received further depilation with the Alexandrite laser. All are now healed with no reported complications. All patients found the procedure painful and received local anaesthetic.

CONCLUSIONS

Laser depilation in the natal cleft is by no means a cure for pilonidal disease. Removal of hair by this method represents an alternative and effective method of hair removal and, although long lasting, is only temporary. However, it allows the sinuses to heal rapidly. It is relatively safe, and simple to teach, with few complications. It should thus be considered as an aid to healing the problem pilonidal sinus.

In vivo targeting of malignant melanoma by 125Iodine- and 99mTechnetium-labeled single-chain Fv fragments against high molecular weight melanoma-associated antigen

Monoclonal antibodies (MAbs) against high-molecular-weight melanoma-associated antigen (HMW-MAA) have been used in vivo to target melanoma. More recently, single chain Fv (scFv) antibody fragments against HMW-MAA have been described that may improve melanoma targeting. However, there have been few in vivo studies with antimelanoma scFvs because these have proved difficult to label with isotopes (e.g., 99mTc) suitable for imaging. We have generated a series of scFvs against HMW-MAA by chain shuffling and antibody phage selection on melanoma cells. In preliminary experiments we identified one scFv (RAFT3) as suitable for in vivo melanoma targeting. Direct radiolabeling of RAFT3 scFv with 99mTc was simple, yielding a radiochemical purity of >90%. The label remained stable for 24 h in vitro. 125I- and 99mTc-labeled RAFT3 scFv were tested in a nude mouse xenograft model for human melanoma and were compared with the parent MAb LHM2 and its F(ab')2 fragment versus nonmelanoma-specific MAb and scFv. RAFT3 scFv accumulated specifically in the tumor and showed greater tumor specificity compared with LHM2 with faster pharmacokinetics (t(1/2)alpha, 8 min; t(1/2)beta, 189 min; and t(1/2)alpha, 37 min; t(1/2)beta, 384 min, respectively) and reduced background in liver, lung, and spleen. Nonspecific accumulation of 99mTc-labeled RAFT3 scFv in the kidney was high but tumor:normal tissue ratios were better compared with 125I-labeled RAFT3 scFv and LHM2 F(ab')2. Overall, tumor-targeting efficiency at equivalent time points was scFv > IgG > F(ab')2 in good agreement with previously described scFvs engineered for 99mTc labeling. We discuss the potential use of RAFT3 scFv for imaging and therapy of metastatic melanoma.

Are triglyceride breast implants really biocompatible?

A case of augmentation mammaplasty with triglyceride implants is presented. Histological examination of the capsules 3 years postimplantation showed retained, irregular, refractile yellow-brown fragments embedded in granulomatous tissue.