206 REPORT OF THE HARVARD AFRICAN EXPEDITION 
tive tissue which extend up to the surface of the stratum mucosum. Some of 
the waving connective tissue fibers are so thick as to resemble in size microfilariae. 
No elastic fibers can be distinguished in these areas, which is in marked con- 
trast to what is usually observed in ordinary cutaneous scar tissue. In other 
places the tissue is rich in long spindle nuclei, and the growth otherwise consists 
of dense fibrous tissue, while in still other areas the fibroglia fibrils are distributed 
in thin strands between layers or bands of the coarser collagen fibers. ‘These 
appearances are especially marked in the sections stained by Mallory’s connec- 
tive tissue stain (No. 187, page 247). There are good numbers of blood vessels 
within the tumors and in many areas there is slight infiltration and proliferations 
of the cells about them. However, the proliferation and infiltration is not marked 
and the infiltration does not extend into the surrounding tissue for any great 
distance. For the most part, the tumor is strikingly free from infiltration with 
cells. The proliferation of the fibroblasts is a much more striking feature than 
the proliferation of the vascular endothelium. On the whole, the tissues show a 
marked regenerative process on the part of the fibroblasts with little or no endo- 
thelial or lymphocytic infiltration. 
In places in other sections of the larger tumor the papillae are preserved. In 
some areas they are fewer in number and in others almost normal in number but 
considerably flattened and shortened. 
In a section from the younger tumor, the papillae are even increased in number 
or are irregular in distribution, and in places, lengthened. In this section the 
corium is richer in nuclei, many of which are rounded, others are of spindle 
form, and arranged longitudinally along the vessels. In still another area of 
this section, just beneath the basal layer of the stratum mucosum, the entire 
field of the microscope (with ocular K8 and objective D, Zeiss), is occupied by 
proliferated cells with rounded or irregular shaped nuclei. Here there are very 
few connective tissue fibers visible and the appearance suggests sarcomatous 
changes. Just outside of it, however, the tissue resembles that of a cicatrizing 
fibrosarcoma. Here there are closely approximated broad bundles of fibers in 
which spindle-shaped cellular elements are present. 
In some of the pieces, particularly of the larger tumors, no sections of hairs 
and glands are found. In the younger tumor, while in places the epidermis is 
greatly thinned, and the stratum corneum, and mucosum are represented only 
by very thin layers of cells, in other portions of the same tumor the epidermis is 
normal and both hairs and sweat glands are present in the corneum. 
Keloid tumors of such extent and size as observed in Case 384 are rare even 
in Africa. 
Van den Branden,’ who has had excellent opportunities for many years in 
the Congo for the observation of a large amount of clinical and pathological 
material, in reporting upon the clinical condition which he illustrates of a very 
similar case to our own, refers to the great rarity of such extensive keloid lesions. 
Gromier ” has recently reported from New Guinea a case in a woman, aged 
1 Van den Branden: Bull. Soc. Path. Exot. (1917), X, 39. 
? Gromier: Bull. Soc. Path. Exot. (1927), XX, 553. 
