Wesley Wu, MD

To the Editor:

Trauma from a pencil tip can sometimes result in a fragment of lead being left embedded within the skin. Pencil lead is composed of 66% graphite carbon, 26% aluminum silicate, and 8% paraffin.^1,2 While the toxicity of these individual elements is low, paraffin can cause nonallergic foreign-body reactions, aluminum silicate can induce epithelioid granulomatous reactions, and graphite has been reported to cause chronic granulomatous reactions in the lungs of those who work with graphite.² Penetrating trauma with a pencil can result in the formation of a cutaneous granulomatous reaction that can sometimes occur years to decades after the initial injury.^3,4 Several cases of pencil-core granulomas have been published, with lag times between the initial trauma and lesion growth as long as 58 years.^1-10 The pencil-core granuloma may simulate malignant melanoma, as it presents clinically as a growing, darkly pigmented lesion, thus prompting biopsy. We present a case of a pencil-core granuloma that began to grow 62 years after the initial trauma.

A 72-year-old woman was referred to our clinic for evaluation of a dark nodule on the forehead. The lesion had been present since the age of 10 years, reportedly from an accidental stabbing with a pencil. The lesion had been flat, stable, and asymptomatic since the trauma occurred; however, the patient reported that approximately 9 months prior to presentation, it had started growing and became painful. Physical examination revealed a 1.0-cm, round, bluish-black nodule on the right superior forehead (Figure 1A). No satellite lesions or local lymphadenopathy were noted on general examination.

An elliptical excision of the lesion with 1-cm margins revealed a bluish-black mass extending through the dermis, through the frontalis muscle, and into the periosteum and frontal bone (Figure 1B). A No. 15 blade was then used to remove the remaining pigment from the outer table of the frontal bone. Histopathologic findings demonstrated a sarcoidal granulomatous dermatitis associated with abundant, nonpolarizable, black, granular pigment consistent with carbon tattoo. This foreign material was readily identifiable in large extracellular deposits and also within histiocytes, including numerous multinucleated giant cells (Figure 2). Immunostaining for MART-1 and SOX-10 antigens failed to demonstrate a melanocytic proliferation. These findings were consistent with a sarcoidal foreign-body granulomatous reaction to carbon tattoo following traumatic graphite implantation.

Granulomatous reactions to carbon tattoo may be sarcoidal (foreign-body granulomatous dermatitis), palisading, or rarely tuberculoid (caseating). Sarcoidal granulomatous tattoo reactions may occur in patients with sarcoidosis due to koebnerization, and histology alone is not discriminatory; however, in our patient, the absence of underlying sarcoidosis or clinical or histologic findings of sarcoidosis outside of the site of the pencil-core granuloma excluded that possibility.¹¹ Pencil-core granulomas are characterized by a delayed foreign-body reaction to retained fragments of lead often years following a penetrating trauma with a pencil. Previous reports have described various lag times from injury to lesion growth of up to 58 years.^1-10 Our patient claimed to have noticed the lesion growing and becoming painful only after a 62-year lag time following the initial trauma. To our knowledge, this is the longest lag time between the initial pencil injury and induction of the foreign-body reaction reported in the literature. Clinically, the lesion appeared and behaved very similar to a melanoma, prompting further treatment and evaluation.

It has been suggested that the lag period between the initial trauma and the rapid growth of the lesion may correspond to the amount of time required for the breakdown of the pencil lead to a critical size followed by the dispersal of those particles within the interstitium, where they can induce a granulomatous reaction.^1,2,9 One case described a patient who reported that the growth and clinical change of the pencil-core granuloma only started when the patient accidentally hit the area where the trauma had occurred 31 years prior.¹ This additional trauma may have caused further mechanical breakdown of the lead to set off the tissue reaction. In our case, the patient did not recall any additional trauma to the head prior to the onset of growth of the nodule on the forehead.

Our case indicates that carbon tattoo may be a possible sequela of a penetrating injury from a pencil with retained pencil lead fragments; however, many of these carbon tattoos may remain stable throughout the remainder of the patient’s life. Carbon tattoo alone does not necessitate surgical treatment, but when an evolving lesion has a clinical differential diagnosis that includes a melanocytic neoplasia, biopsy or complete removal for histopathologic evaluation is warranted.

To the Editor:

Trauma from a pencil tip can sometimes result in a fragment of lead being left embedded within the skin. Pencil lead is composed of 66% graphite carbon, 26% aluminum silicate, and 8% paraffin.^1,2 While the toxicity of these individual elements is low, paraffin can cause nonallergic foreign-body reactions, aluminum silicate can induce epithelioid granulomatous reactions, and graphite has been reported to cause chronic granulomatous reactions in the lungs of those who work with graphite.² Penetrating trauma with a pencil can result in the formation of a cutaneous granulomatous reaction that can sometimes occur years to decades after the initial injury.^3,4 Several cases of pencil-core granulomas have been published, with lag times between the initial trauma and lesion growth as long as 58 years.^1-10 The pencil-core granuloma may simulate malignant melanoma, as it presents clinically as a growing, darkly pigmented lesion, thus prompting biopsy. We present a case of a pencil-core granuloma that began to grow 62 years after the initial trauma.

A 72-year-old woman was referred to our clinic for evaluation of a dark nodule on the forehead. The lesion had been present since the age of 10 years, reportedly from an accidental stabbing with a pencil. The lesion had been flat, stable, and asymptomatic since the trauma occurred; however, the patient reported that approximately 9 months prior to presentation, it had started growing and became painful. Physical examination revealed a 1.0-cm, round, bluish-black nodule on the right superior forehead (Figure 1A). No satellite lesions or local lymphadenopathy were noted on general examination.

An elliptical excision of the lesion with 1-cm margins revealed a bluish-black mass extending through the dermis, through the frontalis muscle, and into the periosteum and frontal bone (Figure 1B). A No. 15 blade was then used to remove the remaining pigment from the outer table of the frontal bone. Histopathologic findings demonstrated a sarcoidal granulomatous dermatitis associated with abundant, nonpolarizable, black, granular pigment consistent with carbon tattoo. This foreign material was readily identifiable in large extracellular deposits and also within histiocytes, including numerous multinucleated giant cells (Figure 2). Immunostaining for MART-1 and SOX-10 antigens failed to demonstrate a melanocytic proliferation. These findings were consistent with a sarcoidal foreign-body granulomatous reaction to carbon tattoo following traumatic graphite implantation.

Granulomatous reactions to carbon tattoo may be sarcoidal (foreign-body granulomatous dermatitis), palisading, or rarely tuberculoid (caseating). Sarcoidal granulomatous tattoo reactions may occur in patients with sarcoidosis due to koebnerization, and histology alone is not discriminatory; however, in our patient, the absence of underlying sarcoidosis or clinical or histologic findings of sarcoidosis outside of the site of the pencil-core granuloma excluded that possibility.¹¹ Pencil-core granulomas are characterized by a delayed foreign-body reaction to retained fragments of lead often years following a penetrating trauma with a pencil. Previous reports have described various lag times from injury to lesion growth of up to 58 years.^1-10 Our patient claimed to have noticed the lesion growing and becoming painful only after a 62-year lag time following the initial trauma. To our knowledge, this is the longest lag time between the initial pencil injury and induction of the foreign-body reaction reported in the literature. Clinically, the lesion appeared and behaved very similar to a melanoma, prompting further treatment and evaluation.

It has been suggested that the lag period between the initial trauma and the rapid growth of the lesion may correspond to the amount of time required for the breakdown of the pencil lead to a critical size followed by the dispersal of those particles within the interstitium, where they can induce a granulomatous reaction.^1,2,9 One case described a patient who reported that the growth and clinical change of the pencil-core granuloma only started when the patient accidentally hit the area where the trauma had occurred 31 years prior.¹ This additional trauma may have caused further mechanical breakdown of the lead to set off the tissue reaction. In our case, the patient did not recall any additional trauma to the head prior to the onset of growth of the nodule on the forehead.

Our case indicates that carbon tattoo may be a possible sequela of a penetrating injury from a pencil with retained pencil lead fragments; however, many of these carbon tattoos may remain stable throughout the remainder of the patient’s life. Carbon tattoo alone does not necessitate surgical treatment, but when an evolving lesion has a clinical differential diagnosis that includes a melanocytic neoplasia, biopsy or complete removal for histopathologic evaluation is warranted.

To the Editor:

Trauma from a pencil tip can sometimes result in a fragment of lead being left embedded within the skin. Pencil lead is composed of 66% graphite carbon, 26% aluminum silicate, and 8% paraffin.^1,2 While the toxicity of these individual elements is low, paraffin can cause nonallergic foreign-body reactions, aluminum silicate can induce epithelioid granulomatous reactions, and graphite has been reported to cause chronic granulomatous reactions in the lungs of those who work with graphite.² Penetrating trauma with a pencil can result in the formation of a cutaneous granulomatous reaction that can sometimes occur years to decades after the initial injury.^3,4 Several cases of pencil-core granulomas have been published, with lag times between the initial trauma and lesion growth as long as 58 years.^1-10 The pencil-core granuloma may simulate malignant melanoma, as it presents clinically as a growing, darkly pigmented lesion, thus prompting biopsy. We present a case of a pencil-core granuloma that began to grow 62 years after the initial trauma.

A 72-year-old woman was referred to our clinic for evaluation of a dark nodule on the forehead. The lesion had been present since the age of 10 years, reportedly from an accidental stabbing with a pencil. The lesion had been flat, stable, and asymptomatic since the trauma occurred; however, the patient reported that approximately 9 months prior to presentation, it had started growing and became painful. Physical examination revealed a 1.0-cm, round, bluish-black nodule on the right superior forehead (Figure 1A). No satellite lesions or local lymphadenopathy were noted on general examination.

An elliptical excision of the lesion with 1-cm margins revealed a bluish-black mass extending through the dermis, through the frontalis muscle, and into the periosteum and frontal bone (Figure 1B). A No. 15 blade was then used to remove the remaining pigment from the outer table of the frontal bone. Histopathologic findings demonstrated a sarcoidal granulomatous dermatitis associated with abundant, nonpolarizable, black, granular pigment consistent with carbon tattoo. This foreign material was readily identifiable in large extracellular deposits and also within histiocytes, including numerous multinucleated giant cells (Figure 2). Immunostaining for MART-1 and SOX-10 antigens failed to demonstrate a melanocytic proliferation. These findings were consistent with a sarcoidal foreign-body granulomatous reaction to carbon tattoo following traumatic graphite implantation.

Granulomatous reactions to carbon tattoo may be sarcoidal (foreign-body granulomatous dermatitis), palisading, or rarely tuberculoid (caseating). Sarcoidal granulomatous tattoo reactions may occur in patients with sarcoidosis due to koebnerization, and histology alone is not discriminatory; however, in our patient, the absence of underlying sarcoidosis or clinical or histologic findings of sarcoidosis outside of the site of the pencil-core granuloma excluded that possibility.¹¹ Pencil-core granulomas are characterized by a delayed foreign-body reaction to retained fragments of lead often years following a penetrating trauma with a pencil. Previous reports have described various lag times from injury to lesion growth of up to 58 years.^1-10 Our patient claimed to have noticed the lesion growing and becoming painful only after a 62-year lag time following the initial trauma. To our knowledge, this is the longest lag time between the initial pencil injury and induction of the foreign-body reaction reported in the literature. Clinically, the lesion appeared and behaved very similar to a melanoma, prompting further treatment and evaluation.

It has been suggested that the lag period between the initial trauma and the rapid growth of the lesion may correspond to the amount of time required for the breakdown of the pencil lead to a critical size followed by the dispersal of those particles within the interstitium, where they can induce a granulomatous reaction.^1,2,9 One case described a patient who reported that the growth and clinical change of the pencil-core granuloma only started when the patient accidentally hit the area where the trauma had occurred 31 years prior.¹ This additional trauma may have caused further mechanical breakdown of the lead to set off the tissue reaction. In our case, the patient did not recall any additional trauma to the head prior to the onset of growth of the nodule on the forehead.

Our case indicates that carbon tattoo may be a possible sequela of a penetrating injury from a pencil with retained pencil lead fragments; however, many of these carbon tattoos may remain stable throughout the remainder of the patient’s life. Carbon tattoo alone does not necessitate surgical treatment, but when an evolving lesion has a clinical differential diagnosis that includes a melanocytic neoplasia, biopsy or complete removal for histopathologic evaluation is warranted.

The flexible scalpel blade (FSB) is a 2-sided handheld razor blade that serves as a pivotal instrument in certain dermatologic procedures. Its unrivaled sharpness¹ permits pinpoint precision for shave biopsies, excisions of superficial lesions,² scar contouring, and harvesting of split-thickness skin grafts.³ Given its flexibility and long edge, considerable manual dexterity and skill are required to maximize its full potential.

Practice Gap

Prior to practicing on live patients, students on clinical rotation would benefit from in vitro skin simulators to practice correct hand position, FSB control for concave and convex surface cutting, and safety. Prior practice models have included mannequins, tomatoes, and eggplants^.4,5 Here, the authors recommend the use of a banana (genus Musa). In addition to its year-round availability, economic feasibility, simplicity, and portability, the banana has colored skin that well represents the epidermis, dermis, and subcutaneous tissue, allowing for visual feedback. Furthermore, its contour irregularities simulate convexities and concavities for various anatomic locations. Although the firmness of a yellow-green banana provides immediate tissue feedback, the softness and pliability of a ripe banana simulates the consistency of older skin and the use of appropriate traction.

Tools

To begin, one simply requires a marking pen, banana, and razor blade. Various shapes, including a circle, ellipse, rectangle, trapezoid, triangle, and multilobed lesion are demarcated by students or attendings (Figure 1). Careful removal of the pieces helps students improve dexterity, develop feel for the entire edge of the razor blade, and acquire muscle memory for these skilled movements (Figure 2). Three-dimensional spatial reasoning is honed with practice using the FSB to control appropriate thickness and defect depth while creating a smooth bevel around the entire perimeter, which is important for optimal cosmesis in second intention healing or grafting. The shallower the defect created, the faster the healing and the greater the reduction in contracture. Although downward pressure is important to prevent buttonholing or tearing of the tissue being removed, the angle of the blade relative to the tissue must be assessed at all points, and the alteration in color and fiber orientation signify change in depth of the banana peel.

The Technique

To handle the FSB, one can hold the lateral edges of the blade between the thumb and index finger or between the thumb and middle finger. The thumb and index finger position allows for additional flexible working space and visualization, increased traction by the remaining 3 fingers, and greater ease of removal of lesions with considerable height. The thumb and middle finger hold allows for versatile use of the index finger of the same hand for stabilizing the center of the blade, fixing the tissue on the FSB while it is removed, and sliding the specimen off the FSB. It is important to maintain a fixed distance from the blade to the metacarpals at all times to ensure smooth advancement of the blade and visualization. Beginners can lift the pinky finger of the hand holding the FSB and move the finger up and down to control the angle of the blade.

Practice Implications

Generally, we utilize various techniques of shaving using the FSB. We approach the target lesion 2 to 3 mm from the marked location and slide parallel to the skin surface and perpendicular to the lesion until the epidermis is penetrated. Second, we advance the blade toward the lesion with careful attention paid to the perimeter of the lesion and the points of contact of the FSB. For lesions with hardier consistencies, a sawing motion of the blade is employed, which also requires controlled tilting of the wrist to maintain an even depth and smooth bevel. To cut deeper, flexing the FSB with lateral pressure is helpful. More shallow lesions require the instrument to be flatter and less bowed. When finishing the shave, it is important to start angling the blade upward early, either at the center of the targeted lesion or 2 to 3 mm before the demarcated edge of the skin graft, while applying traction away from the lesion and slight downward pressure with the nondominant hand.

For larger lesions, the perimeter may be more difficult to remove precisely and can be achieved by rotating the blade around the lesion with focus on one point of contact of the FSB to cut and glide through the tissue’s perimeter. To achieve a more exact wound edge and to preclude jagged borders, a No. 15 blade can be used to score the perimeter very superficially to the papillary dermis prior to shave removal. The main disadvantage, however, is that the beveled edge is removed.

In summary, the FSB is an exceptional tool for biopsies, tumor removal, scar contouring, and split-thickness skin grafts. Through the banana practice model, one can attain fine control and reap the benefits of the FSB after meticulous and dedicated training.

The flexible scalpel blade (FSB) is a 2-sided handheld razor blade that serves as a pivotal instrument in certain dermatologic procedures. Its unrivaled sharpness¹ permits pinpoint precision for shave biopsies, excisions of superficial lesions,² scar contouring, and harvesting of split-thickness skin grafts.³ Given its flexibility and long edge, considerable manual dexterity and skill are required to maximize its full potential.

Practice Gap

Prior to practicing on live patients, students on clinical rotation would benefit from in vitro skin simulators to practice correct hand position, FSB control for concave and convex surface cutting, and safety. Prior practice models have included mannequins, tomatoes, and eggplants^.4,5 Here, the authors recommend the use of a banana (genus Musa). In addition to its year-round availability, economic feasibility, simplicity, and portability, the banana has colored skin that well represents the epidermis, dermis, and subcutaneous tissue, allowing for visual feedback. Furthermore, its contour irregularities simulate convexities and concavities for various anatomic locations. Although the firmness of a yellow-green banana provides immediate tissue feedback, the softness and pliability of a ripe banana simulates the consistency of older skin and the use of appropriate traction.

Tools

To begin, one simply requires a marking pen, banana, and razor blade. Various shapes, including a circle, ellipse, rectangle, trapezoid, triangle, and multilobed lesion are demarcated by students or attendings (Figure 1). Careful removal of the pieces helps students improve dexterity, develop feel for the entire edge of the razor blade, and acquire muscle memory for these skilled movements (Figure 2). Three-dimensional spatial reasoning is honed with practice using the FSB to control appropriate thickness and defect depth while creating a smooth bevel around the entire perimeter, which is important for optimal cosmesis in second intention healing or grafting. The shallower the defect created, the faster the healing and the greater the reduction in contracture. Although downward pressure is important to prevent buttonholing or tearing of the tissue being removed, the angle of the blade relative to the tissue must be assessed at all points, and the alteration in color and fiber orientation signify change in depth of the banana peel.

The Technique

To handle the FSB, one can hold the lateral edges of the blade between the thumb and index finger or between the thumb and middle finger. The thumb and index finger position allows for additional flexible working space and visualization, increased traction by the remaining 3 fingers, and greater ease of removal of lesions with considerable height. The thumb and middle finger hold allows for versatile use of the index finger of the same hand for stabilizing the center of the blade, fixing the tissue on the FSB while it is removed, and sliding the specimen off the FSB. It is important to maintain a fixed distance from the blade to the metacarpals at all times to ensure smooth advancement of the blade and visualization. Beginners can lift the pinky finger of the hand holding the FSB and move the finger up and down to control the angle of the blade.

Practice Implications

Generally, we utilize various techniques of shaving using the FSB. We approach the target lesion 2 to 3 mm from the marked location and slide parallel to the skin surface and perpendicular to the lesion until the epidermis is penetrated. Second, we advance the blade toward the lesion with careful attention paid to the perimeter of the lesion and the points of contact of the FSB. For lesions with hardier consistencies, a sawing motion of the blade is employed, which also requires controlled tilting of the wrist to maintain an even depth and smooth bevel. To cut deeper, flexing the FSB with lateral pressure is helpful. More shallow lesions require the instrument to be flatter and less bowed. When finishing the shave, it is important to start angling the blade upward early, either at the center of the targeted lesion or 2 to 3 mm before the demarcated edge of the skin graft, while applying traction away from the lesion and slight downward pressure with the nondominant hand.

For larger lesions, the perimeter may be more difficult to remove precisely and can be achieved by rotating the blade around the lesion with focus on one point of contact of the FSB to cut and glide through the tissue’s perimeter. To achieve a more exact wound edge and to preclude jagged borders, a No. 15 blade can be used to score the perimeter very superficially to the papillary dermis prior to shave removal. The main disadvantage, however, is that the beveled edge is removed.

In summary, the FSB is an exceptional tool for biopsies, tumor removal, scar contouring, and split-thickness skin grafts. Through the banana practice model, one can attain fine control and reap the benefits of the FSB after meticulous and dedicated training.

The flexible scalpel blade (FSB) is a 2-sided handheld razor blade that serves as a pivotal instrument in certain dermatologic procedures. Its unrivaled sharpness¹ permits pinpoint precision for shave biopsies, excisions of superficial lesions,² scar contouring, and harvesting of split-thickness skin grafts.³ Given its flexibility and long edge, considerable manual dexterity and skill are required to maximize its full potential.

Practice Gap

Prior to practicing on live patients, students on clinical rotation would benefit from in vitro skin simulators to practice correct hand position, FSB control for concave and convex surface cutting, and safety. Prior practice models have included mannequins, tomatoes, and eggplants^.4,5 Here, the authors recommend the use of a banana (genus Musa). In addition to its year-round availability, economic feasibility, simplicity, and portability, the banana has colored skin that well represents the epidermis, dermis, and subcutaneous tissue, allowing for visual feedback. Furthermore, its contour irregularities simulate convexities and concavities for various anatomic locations. Although the firmness of a yellow-green banana provides immediate tissue feedback, the softness and pliability of a ripe banana simulates the consistency of older skin and the use of appropriate traction.

Tools

To begin, one simply requires a marking pen, banana, and razor blade. Various shapes, including a circle, ellipse, rectangle, trapezoid, triangle, and multilobed lesion are demarcated by students or attendings (Figure 1). Careful removal of the pieces helps students improve dexterity, develop feel for the entire edge of the razor blade, and acquire muscle memory for these skilled movements (Figure 2). Three-dimensional spatial reasoning is honed with practice using the FSB to control appropriate thickness and defect depth while creating a smooth bevel around the entire perimeter, which is important for optimal cosmesis in second intention healing or grafting. The shallower the defect created, the faster the healing and the greater the reduction in contracture. Although downward pressure is important to prevent buttonholing or tearing of the tissue being removed, the angle of the blade relative to the tissue must be assessed at all points, and the alteration in color and fiber orientation signify change in depth of the banana peel.

The Technique

To handle the FSB, one can hold the lateral edges of the blade between the thumb and index finger or between the thumb and middle finger. The thumb and index finger position allows for additional flexible working space and visualization, increased traction by the remaining 3 fingers, and greater ease of removal of lesions with considerable height. The thumb and middle finger hold allows for versatile use of the index finger of the same hand for stabilizing the center of the blade, fixing the tissue on the FSB while it is removed, and sliding the specimen off the FSB. It is important to maintain a fixed distance from the blade to the metacarpals at all times to ensure smooth advancement of the blade and visualization. Beginners can lift the pinky finger of the hand holding the FSB and move the finger up and down to control the angle of the blade.

Practice Implications

Generally, we utilize various techniques of shaving using the FSB. We approach the target lesion 2 to 3 mm from the marked location and slide parallel to the skin surface and perpendicular to the lesion until the epidermis is penetrated. Second, we advance the blade toward the lesion with careful attention paid to the perimeter of the lesion and the points of contact of the FSB. For lesions with hardier consistencies, a sawing motion of the blade is employed, which also requires controlled tilting of the wrist to maintain an even depth and smooth bevel. To cut deeper, flexing the FSB with lateral pressure is helpful. More shallow lesions require the instrument to be flatter and less bowed. When finishing the shave, it is important to start angling the blade upward early, either at the center of the targeted lesion or 2 to 3 mm before the demarcated edge of the skin graft, while applying traction away from the lesion and slight downward pressure with the nondominant hand.

For larger lesions, the perimeter may be more difficult to remove precisely and can be achieved by rotating the blade around the lesion with focus on one point of contact of the FSB to cut and glide through the tissue’s perimeter. To achieve a more exact wound edge and to preclude jagged borders, a No. 15 blade can be used to score the perimeter very superficially to the papillary dermis prior to shave removal. The main disadvantage, however, is that the beveled edge is removed.

In summary, the FSB is an exceptional tool for biopsies, tumor removal, scar contouring, and split-thickness skin grafts. Through the banana practice model, one can attain fine control and reap the benefits of the FSB after meticulous and dedicated training.